U.S. patent application number 12/115408 was filed with the patent office on 2009-12-31 for universal non-volatile memory card used with various different standard cards containing a memory controller.
This patent application is currently assigned to SanDisk Corporation. Invention is credited to Bo Eric Ericsson, Eliyahou Harari, Robert F. Wallace.
Application Number | 20090321530 12/115408 |
Document ID | / |
Family ID | 32229761 |
Filed Date | 2009-12-31 |
United States Patent
Application |
20090321530 |
Kind Code |
A1 |
Harari; Eliyahou ; et
al. |
December 31, 2009 |
UNIVERSAL NON-VOLATILE MEMORY CARD USED WITH VARIOUS DIFFERENT
STANDARD CARDS CONTAINING A MEMORY CONTROLLER
Abstract
A mother/daughter card non-volatile memory system includes a
daughter card containing the memory and a mother card containing
the memory controller and host interface circuits. The daughter
memory card contains as little more than the memory cell array as
is practical, in order to minimize its cost, and has an interface
for connecting with a variety of mother controller cards having
physical attributes and host interfaces according to a number of
different published or proprietary memory card standards. Different
types of memory cards may be used when the operating parameters of
the memory are stored within it in a protected location, the mother
card controller then reading these parameters and adapting its
operation accordingly. A radio frequency antenna may be included on
a surface of the card along with its electrical contacts, in order
to provide a radio frequency identification function.
Inventors: |
Harari; Eliyahou; (Los
Gatos, CA) ; Ericsson; Bo Eric; (Los Gatos, CA)
; Wallace; Robert F.; (Sunnyvale, CA) |
Correspondence
Address: |
SANDISK CORPORATION;JENKINS, WILSON, TAYLOR & HUNT, P.A.
SUITE 1200 UNIVERSITY TOWER, 3100 TOWER BOULEVARD
DURHAM
NC
27707
US
|
Assignee: |
SanDisk Corporation
Sunnyvale
CA
|
Family ID: |
32229761 |
Appl. No.: |
12/115408 |
Filed: |
May 5, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10293985 |
Nov 13, 2002 |
7367503 |
|
|
12115408 |
|
|
|
|
Current U.S.
Class: |
235/492 |
Current CPC
Class: |
H01L 2924/01057
20130101; G06F 13/387 20130101; H01L 2224/48091 20130101; H01L
2225/06562 20130101; H01L 2924/181 20130101; H01L 2924/01078
20130101; H01L 2924/00014 20130101; H01L 2224/48091 20130101; H01L
2924/00012 20130101; H01L 2924/181 20130101; G06K 19/077 20130101;
G06K 19/07741 20130101; G06K 19/067 20130101 |
Class at
Publication: |
235/492 |
International
Class: |
G06K 19/06 20060101
G06K019/06 |
Claims
1-24. (canceled)
25. A method of obtaining and using a nonvolatile memory card,
comprising: obtaining at least one of the memory cards in a form
attached to a larger storage card, removing said memory card from
the storage card and placing it in a device that generates data
desired to be stored on the memory card, storing such data on the
memory card, thereafter removing said at least one memory card from
the device and re-attaching said memory card to the storage card,
and providing an appropriate surface on said storage card for
noting the contents of the data stored on the memory card on a
surface of the storage card.
26. The method according to claim 25 wherein said storage card has
substantially the same length and width as credit cards or smart
cards.
27. A hand-held substrate card, comprising: a first area on a
surface of the substrate card to which one or more electronic cards
smaller than the substrate surface and each containing a
non-volatile memory is attached, a second area on the surface of
the substrate that is treated to allow writing by pen or pencil,
thereby enabling a user to note the data contents of said one or
more memory cards attached thereto.
28. The substrate card of claim 27, additionally containing a
microprocessor or microcontroller circuitry which can interface
with said one or more memory cards to read or change the data
contained within said one or more memory cards, said microprocessor
or microcontroller circuitry also capable of communication with an
external system to transfer data between said external system and
said one or more memory cards.
29. The substrate card of claim 28 wherein said microprocessor or
microcontroller circuitry contains security functionality to
authenticate or block said communication between itself, an
external system, and said one or more memory cards.
30-57. (canceled)
58. The substrate card of claim 28 wherein said communication with
an external system includes a published communication standard
including various USB standards, IEEE 1394, ISO/IEC 7816, TCP/IP,
or a form of RF communication including Bluetooth and IEEE 802.11
wireless protocols.
59. The substrate card of claim 29 wherein said communication with
an external system includes a published communication standard
including various USB standards, IEEE 1394, ISO/IEC 7816, TCP/IP,
or a form of RF communication including Bluetooth and IEEE 802.11
wireless protocols.
Description
FIELD OF THE INVENTION
[0001] This invention relates generally to the use and structure of
removable electronic circuit cards having different mechanical
and/or electrical interfaces, particularly those including mass
non-volatile integrated circuit memory.
BACKGROUND OF THE INVENTION
[0002] Electronic circuit cards, including non-volatile memory
cards, have been commercially implemented according to a number of
well-known standards. Memory cards are used with personal
computers, cellular telephones, personal digital assistants,
digital cameras, portable audio players and other host electronic
devices for the storage of large amounts of data. Such cards
usually contain a non-volatile semiconductor memory cell array
along with a controller that controls operation of the memory cell
array and interfaces with a host to which the card connected.
Several of the same type of card may be interchanged in a host card
slot designed to accept that type of card. However, the development
of the many electronic card standards has created different types
of cards that are incompatible with each other in various degrees.
A card made according to one standard is usually not useable with a
host designed to operate with a card of another standard.
[0003] One such standard, the PC Card Standard, provides
specifications for three types of PC Cards. Originally released in
1990, the PC Card Standard now contemplates three forms of a
rectangular card measuring 85.6 mm. by 54.0 mm., having thicknesses
of 3.3 mm. (Type I), 5.0 mm. (Type II) and 10.5 mm. (Type III). An
electrical connector, which engages pins of a slot in which the
card is removably inserted, is provided along a narrow edge of the
card. PC Card slots are included in current notebook personal
computers, as well as in other host equipment, particularly
portable devices. The PC Card Standard is a product of the Personal
Computer Memory Card International Association (PCMCIA). The latest
release of the PC Card Standard from the PCMCIA is dated February
1995, which standard is incorporated herein by this reference.
[0004] In 1994, SanDisk Corporation introduced the CompactFlash.TM.
card (CF.TM. card) that is functionally compatible with the PC Card
but is much smaller. The CF.TM. card is rectangularly shaped with
dimensions of 43 mm. by 36 mm. and a thickness of 3.3 mm., and has
a female pin connector along one edge. The CF.TM. card is widely
used with cameras for the storage of video data. A passive adapter
card is available, in which the CF.TM. card fits, that then can be
inserted into a PC Card slot of a host computer or other device.
The controller within the CF.TM. card operates with the card's
flash memory to provide an ATA interface at its connector. That is,
a host with which a CF.TM. card is connected interfaces with the
card as if it is a disk drive. Specifications for the card have
been developed by the CompactFlash Association, a current version
of these specifications being 1.4, which standard is incorporated
herein by this reference.
[0005] The SmartMedia.TM. card is about one-third the size of a PC
Card, having dimensions of 45.0 mm. by 37.0 mm. and is very thin at
only 0.76 mm. thick. Contacts are provided in a defined pattern as
areas on a surface of the card. Its specifications have been
defined by the Solid State Floppy Disk Card (SSFDC) Forum, which
began in 1996. It contains flash memory, particularly of the NAND
type. The SmartMedia.TM. card is intended for use with portable
electronic devices, particularly cameras and audio devices, for
storing large amounts of data. A memory controller is included
either in the host device or in an adapter card in another format
such as one according to the PC Card standard. Physical and
electrical specifications for the SmartMedia.TM. card have been
issued by the SSFDC Forum, a current version of this standard being
1.0, which standard is incorporated herein by this reference.
[0006] Another non-volatile memory card is the MultiMediaCard
(MMC.TM.). The physical and electrical specifications for the
MMC.TM. are given in "The MultiMediaCard System Specification" that
is updated and published from time-to-time by the MultiMediaCard
Association (MMCA). Version 3.1 of that Specification, dated June
2001, is expressly incorporated herein by this reference. MMC.TM.
products having varying storage capacity up to 128 megabytes in a
single card are currently available from SanDisk Corporation. The
MMC.TM. card is rectangularly shaped with a size similar to that of
a postage stamp. The card's dimensions are 32.0 mm. by 24.0 mm. and
1.4 mm. thick, with a row of electrical contacts on a surface of
the card along a narrow edge that also contains a cut-off corner.
These products are described in a "MultiMediaCard Product Manual,"
Revision 2, dated April 2000, published by SanDisk Corporation,
which Manual is expressly incorporated herein by this reference.
Certain aspects of the electrical operation of the MMC.TM. products
are also described in U.S. Pat. No. 6,279,114 and in patent
application Ser. No. 09/186,064, filed Nov. 4, 1998, both by
applicants Thomas N. Toombs and Micky Holtzman, and assigned to
SanDisk Corporation. The physical card structure and a method of
manufacturing it are described in U.S. Pat. No. 6,040,622, assigned
to SanDisk Corporation. Both of these patents and patent
application are expressly incorporated herein by this
reference.
[0007] A modified version of the MMC.TM. card is the later Secure
Digital (SD) card. The SD Card has the same rectangular size as the
MMC.TM. card but with an increased thickness (2.1 mm.) in order to
accommodate an additional memory chip when that is desired. A
primary difference between these two cards is the inclusion in the
SD card of security features for its use to store proprietary data
such as that of music. Another difference between them is that the
SD Card includes additional data contacts in order to enable faster
data transfer between the card and a host. The other contacts of
the SD Card are the same as those of the MMC.TM. card in order that
sockets designed to accept the SD Card can also be made to accept
the MMC.TM. card. This is described in patent application Ser. No.
09/641,023, filed by Cedar et al. on Aug. 17, 2000, which
application is incorporated herein by this reference. The
electrical interface with the SD card is further made to be, for
the most part, backward compatible with the MMC.TM. card, in order
that few changes to the operation of the host need be made in order
to accommodate both types of cards. Specifications for the SD card
are available to member companies from the SD Association
(SDA).
[0008] Another type of memory card is the Subscriber Identity
Module (SIM), the specifications of which are published by the
European Telecommunications Standards Institute (ETSI). A portion
of these specifications appear as GSM 11.11, a recent version being
technical specification ETSI TS 100 977 V8.3.0 (2000-08), entitled
"Digital Cellular Telecommunications System (Phase 2+);
Specification of the Subscriber Identity Module-Mobile Equipment
(SIM-ME) Interface," (GSM 11.11 Version 8.3.0 Release 1999). This
specification is hereby incorporated herein by this reference. Two
types of SIM cards are specified: ID-1 SIM and Plug-in SIM.
[0009] The ID-1 SIM card has a format and layout according to the
ISO/IEC 7810 and 7816 standards of the International Organization
for Standardization (ISO) and the International Electrotechnical
Commission (EC). The ISO/IEC 7810 standard is entitled
"Identification cards--Physical characteristics," second edition,
August 1995. The ISO/IEC 7816 standard has the general title of
"Identification cards--Integrated Circuit(s) Cards with Contacts,"
and consists of parts 1-10 that carry individual dates from 1994
through 2000. These standards, copies of which are available from
the ISO/IEC in Geneva, Switzerland, are expressly incorporated
herein by this reference. The ID-1 SIM card is generally the size
of a credit card, having dimensions of 85.60 mm. by 53.98 mm., with
rounder corners, and a thickness of 0.76 mm. Such a card may have
only memory or may also include a microprocessor, the latter often
being referred to as a "Smart Card." One application of a Smart
Card is as a debit card where an initial credit balance is
decreased every time it is used to purchase a product or a
service.
[0010] The Plug-in SIM is a very small card, smaller than the
MMC.TM. and SD cards. The GSM 11.11 specification referenced above
calls for this card to be a rectangle 25 mm. by 15 mm., with one
corner cut off for orientation, and with the same thickness as the
ID-1 SIM card. A primary use of the Plug-in SIM card is in mobile
telephones and other devices for security against the theft and/or
unauthorized use of the devices, in which case the card stores a
security code personal to the device's owner or user. In both types
of SIM cards, eight electrical contacts (but with as few as five
being used) are specified in the ISO/IEC 7816 standard to be
arranged on a surface of the card for contact by a host
receptacle.
[0011] Sony Corporation developed a non-volatile memory card, sold
as the Memory Stick.TM., that has yet another set of
specifications. Its shape is that of an elongated rectangle having
electrical contacts on a surface adjacent one of its short sides.
The electrical interface through these contacts with a host to
which it is connected is unique.
[0012] As is apparent from the foregoing summary of the primary
electronic card standards, there are many differences in their
physical characteristics including size and shape, in the number,
arrangement and structure of electrical contacts and in the
electrical interface with a host system through those contacts when
the card is inserted into the host card slot. Electronic devices
that use electronic cards are usually made to work with only one
type of card. Adaptors, both active and passive types, have been
provided or proposed to allow some degree of interchangeability of
electronic cards among such host devices. U.S. Pat. No. 6,266,724
of Harari et al. describes use of combinations of mother and
daughter memory cards, which patent is incorporated herein in its
entirety by this reference.
SUMMARY OF THE INVENTION
[0013] According to a primary aspect of the present invention, a
very small (less than the size of a postage stamp) sub-card or
daughter card containing non-volatile memory is removably
connectable with one or more electronic cards or mother cards made
according to different specifications, such as those of two or more
of the above-described incompatible standards, while memory control
and unique host interface functions remain on the mother cards. The
mother cards individually interface, both mechanically and
electrically, with host devices in the same manner as previously.
But the non-volatile memory of each type of mother card has been
removed and a standard memory interface substituted on the mother
card. A universal memory daughter card is removably connectable
with any of several different types of mother cards through the
standard memory card interface. An advantage of the universal
memory card is its reduced size and cost since the memory
controller and host interface electronics reside on the mother
cards. Since primarily only the memory storage cells are included
on the memory card, its cost can be significantly lower than the
memory cards described above that each also contain the memory
controller and host interface. This standard memory interface
between mother card and daughter card is to be distinguished from
the host interface between the mother card and the host. While
various adaptors may now be used to allow otherwise incompatible
memory cards to communicate with a variety hosts, the subject of
this aspect of the present invention is the mother/daughter card
interface using a standardized universal interface.
[0014] According to another aspect of the present invention, such
daughter memory cards may be removably carried by a larger
substrate (such as one the size of a credit card) for distributing,
handling and/or storing, and accessing the very small memory
daughter cards. Because of their relatively low cost, the memory
cards can be used for permanent storage of data. Video data, such
as photographs, and audio data, such as music, are examples of the
use of such memory cards by individuals. A storage card preferably
carries one or more such memory cards and includes a surface area
for the user to write by hand or otherwise uniquely identify or
maintain a record of the data content of the memory card(s)
attached to it. The memory cards may be distributed and sold
through retail channels by selling the storage cards with one or
more memory cards attached to each. The storage card may optionally
include electrical contacts to which contacts of the attached
memory card are connected through the storage card for the purpose
of reading the data stored on the memory card, such as by inserting
the storage card into a reader connected with a personal computer
in the home or office, without having to remove the memory card
from the storage card. Alternatively, the storage card may be sized
according to the standards for a popular one of the cards described
above, such as the Smart Card (ID-1 SE), with the memory card
having a pattern of contacts and position on the storage card
according to that same standard, thereby allowing the storage card
with an attached memory card to be inserted into existing or
suitably adapted card readers and read through the memory card
contacts. Further contacts need not be provided on the storage card
in order to access the memory card.
[0015] Additionally, the storage card for daughter memory cards may
be provided with an intelligent controller capable of communicating
with existing memory card readers using a variety of existing
formats as outlined above for the mother cards. This controller may
even communicate using the popular USB protocol in which case the
storage card becomes functionally equivalent to the combination of
a mother card and a reader and may plug into a passive adaptor
meeting the mechanical standards for a USB connector.
[0016] In yet another variation, the identity of the daughter
card(s) contained on the storage card may be read out using a
contactless RF Identification mode. Suitable RF circuitry may be
included either on the daughter card itself or on the storage card.
In either case the power required to read out data contained in a
predefined portion of the daughter card is provided by the incoming
RF signal. The card then responds by modulating the incoming RF
signal in such a way that the external RF receiver can interpret
the code and thus uniquely identify the daughter card.
[0017] According to a further embodiment of the present invention,
the daughter memory card is made in accordance with one of the
existing card standards but with additional contacts added for
connecting with the standard memory interface of the mother cards.
This then allows the memory card to have a dual function: it can be
used in the same manner as an existing card, directly with the
host, or as a daughter card with one of the mother cards. As an
illustration, contacts are added to the small Plug-in SIM card
described above on the card's surface to surround the existing
eight contacts that are provided as part of the ISO/IEC 7816
standard. The card may then be used in a host device in the same
manner as the Plug-in SIM card, or as a memory daughter card when
coupled with a mother card according to another one of the
standards. For example, the contacts required for communication
using ISO/IEC 7816 protocol may be used during powerup
initialization to identify the card and allow authentication for
access by the host or mother card to the data content of the card.
This communication may then use the additional memory interface
contacts at much higher speeds using the standardized communication
protocol.
[0018] A patent application of Wallace et al., entitled "Use of
Small Electronic Circuit Cards with Different Interfaces in an
Electronic System" describes a combination of memories according to
two different standards in a single memory card that shares a
single set of card contacts. This application Ser. No. 09/633,089,
filed Aug. 4, 2000, is hereby incorporated herein by this
reference.
[0019] According to yet another aspect of the present invention,
provision is made for accommodating future changes to the daughter
card memory when such changes may affect the manner in which the
mother card controller or a host controller needs to operate. A
dedicated portion of the daughter card memory space accessible to
the mother card controller (but preferably not to the user)
contains data of specific operating parameters of the memory. Once
the daughter card is detected, the mother card controller reads
these parameters upon initialization, or whenever a new daughter
memory card is inserted into the mother card receptacle, and then
configures itself to operate the card and its memory accordingly.
The memory system operating parameters that may be set in this way
include algorithms for writing data into the memory, reading data
from the memory, erasing blocks of the memory, correcting errors in
read data, and the creation of a file system. Other parameters
include levels of voltages required by the daughter memory card,
the size of memory cell blocks that are the minimum number of cells
erased together, the size of pages of memory cells within the
blocks that are programmed together and other aspects of large
memory cell block management. The parameters chosen to be stored
for controlling operation of the memory are those expected to
change in the future as the memory technology evolves. Other
parameters may include information about the security features for
content protection, the unique daughter card identification number,
information on how the mother card should handle multi-bit per cell
storage on the daughter card, as well as whether the daughter card
is operable as a "cone time write", multiple write, read only, or
non-memory functions such as applications for optimized operation
of the daughter card in specific hosts. The mother card controller,
and in some cases the host system to which the mother and daughter
cards are connected, then adapt to the parameters stored in a
connected daughter memory card.
[0020] Additional features, aspects and advantages of the present
invention are included in the following description of exemplary
embodiments, which description should be taken in conjunction with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 schematically illustrates specific examples of the
use of a common daughter memory card with three different mother
controller cards having incompatible specifications;
[0022] FIG. 2 is an electronic block diagram that shows the
functions contained in a host device, a mother controller card and
a daughter memory card;
[0023] FIG. 3 illustrates a storage card to which daughter memory
cards are removably attached, and a reader having a slot in which
the storage card may be inserted in order to read data from the
memory cards attached to it;
[0024] FIG. 4 schematically illustrates an application of the
daughter memory card, the storage card and the mother controller
card for taking and storing data of photographs taken by a
camera;
[0025] FIG. 5 schematically illustrates an application of the
daughter memory card and the storage card, without use of the
mother controller card, for taking and storing data of photographs
taken by a camera;
[0026] FIG. 6A is a plan view of a specific example of a daughter
memory card;
[0027] FIG. 6B is a cross-sectional view of the memory card of FIG.
6A, taken at section B-B thereof;
[0028] FIG. 7 shows one example of a receptacle within a mother
controller card or a host device for receiving the memory card of
FIGS. 6A and 6B;
[0029] FIG. 8 shows example mounting details of a surface mounted
daughter card of the type shown in FIGS. 6A and 6B;
[0030] FIG. 9 is a plan view of another example daughter memory
card with surface contacts arranged differently than in the example
of FIG. 6A;
[0031] FIG. 10 is a plan view of a lead frame that can be in the
manufacturer of the card of FIG. 9;
[0032] FIG. 11A is a plan view of a first specific example of the
card shown in FIG. 9 that uses the lead frame of FIG. 10;
[0033] FIG. 11B is an end view of the memory card of FIG. 11A;
[0034] FIG. 11C is a side view of the memory card of FIG. 11B;
[0035] FIG. 12A is a plan view of a second specific example of the
card shown in FIG. 9 that uses the lead frame of FIG. 10;
[0036] FIG. 12B is an end view of the memory card of FIG. 12A;
[0037] FIG. 12C is a side view of the memory card of FIG. 12B;
[0038] FIG. 13 is another example of a storage card with removably
attached memory cards according to FIG. 6A or 9, that is different
than the storage card of FIG. 3; and
[0039] FIG. 1 is a plan view of yet another memory card
example.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0040] FIG. 1 illustrates a common use of a daughter memory card 11
with three different mother cards 13, 14 and 15. The mother card 13
is designed to work with a host device 17 but not with host devices
18 or 19. As an example, the mother card 13 may have the same
physical shape and host electronic interface as a CompactFlash.TM.
card and the host 17 may be a digital camera. Similarly, the mother
card 14 is designed to work with the host device 18 but not with
host devices 17 or 19, and the mother card 15 is designed to work
with the host device 19 but not with host devices 17 or 18. Also as
examples, the mother card 14 may have the same physical shape and
host electronic interface as either of the MMC.TM. or SD cards, and
the host 18 may be a personal organizer. Further, the mother card
15 may have the same physical shape and host electronic interface
as the Memory Stick.TM. card, and the host 19 may be a digital
camcorder or any of a multitude of products currently offered for
sale by Sony Corporation. A card slot 21 of the host 17 is
physically shaped to accept insertion and removal of the mother
card 13. A connector 22 of the mother card 13 mates with a matching
connector within the card slot 21. Similarly, a card slot 23 of the
host 18 accepts the mother card 14, and a card slot 25 of the host
19 accepts the mother card 15. A row of surface contacts 24 on the
mother card 14 is contacted by a matching set of conductive
elements of host card slot 23 (not shown) and a row of surface
contacts 27 on the mother card 15 is contacted by a matching set of
conductive elements of the host card slot 25.
[0041] The daughter memory card 11 is removeably received on each
of the mother cards 13, 14 and 15 by some convenient
electrical/mechanical arrangement thereon, shown to be in example
positions 29, 30, and 31, respectively. Two rows of contacts 33 and
35 are shown on a surface of the memory card 11, as an example, for
mating with a similarly arranged set of contacts within the mother
cards 13, 14 and 15 when the memory card 11 is positioned thereon.
Other contacting arrangements on the daughter card, such as a set
of connecting surfaces on either or both flat surfaces, or contacts
along one or more sides or edges, may be used. In the illustrated
embodiment, each of the mother card 13, 14 and 15 substantially
encloses the daughter card 11 but this is not required. A variety
of methods to mate the cards may be used such as a slot, guide
rail, or click-in-place mechanism. The daughter card may also
include an indentation in a variety of shapes allowing removal with
a narrow object such as a pencil point or nail, and it may also
include a retention detent to ensure reliable contact.
Alternatively, one or all of the mother cards 13, 14 and 15 may
have provisions for retaining the memory card on its outside
surface, such as by having a recessed surface region in the same
shape as the memory card. In either of these examples, electrical
contact is made with the memory card contacts 33 and 35 by
appropriate electrical connectors within either the slot, recess or
other physical memory card receptacle of each mother card. Many
identical memory cards 11 will generally be used, one at a time,
with any given mother card. Blank memory cards can be used in this
way to store data from a host into which the mother card is
inserted, or memory cards with data stored on them may be attached
to a mother card for reading its data by a host into which the
mother card is operably connected.
[0042] The mother card 13, in this example, has all the physical
attributes and electrical host interface of a CompactFlash.TM.
card, as well as a memory controller, but does not contain the mass
non-volatile memory storage that is currently included in such a
card. Rather, that mass memory is included in the daughter memory
card 11 that is connectable with the mother card 13. Further, in
this example, the mother card 14 corresponds to a MMC.TM./SD card
with its mass memory removed and the receptacle 30 provided to
receive the memory card 11 instead. Similarly, in this example, the
mother card 15 corresponds to a Memory Stick.TM. card but with its
mass memory removed and the receptacle 31 provided to receive the
memory card 11 instead. Alternatively, other types of memory cards
having the physical and electrical interface characteristics
according to card standards other than CompactFlash.TM.,
MMC.TM./SD, and Memory Stick.TM., including those described above
in the Background and others, may similarly be modified to remove
their mass memory into the separate memory card 11.
[0043] The memory card 11 may have a capacity of 8, 16, 32, 64, 128
or more megabytes of non-volatile memory, for example of the flash
EEPROM type, or of a one-time programmable memory that can be used
for archival storage purposes. Indeed, memory cards of various
capacities are expected to be sold to end users, so that only the
amount of memory desired for a particular application need be
purchased. The memory card is preferably plastic encased with
electrical contacts of some convenient pattern across one or both
surfaces of the card. The memory card 11 is preferably rectangular
in shape with dimensions less than those of the present MMC.TM. or
SD cards, an example being a card having substantially the same
dimensions as the existing Plug-in SIM card.
[0044] The mother/daughter card combinations may be used with a
variety of hosts. A host typically accepts one or perhaps two types
of memory cards. Use of the memory card 11 separate from the mother
cards that interface directly with various hosts therefore adds the
convenience of being able to easily transfer data between two hosts
that accept incompatible cards. For example, the card 11 can work
with two cameras that are designed to save data of photographs into
respective CompactFlash.TM. and Memory Stick.TM. cards that are
accepted by the hosts' card slots. The daughter memory card 11 can
then be moved between the two cameras. If the data format of
individual photograph files saved by each camera is the same, for
which an existing standard is predominate, a file stored on the
memory card 11 by one camera may be read and processed by the other
camera. The same easy transfer is also made possible when only one
of two hosts is a camera and the other a utilization device, such
as a personal computer, that processes or simply views photographs,
but where the two do not have the same format card slot. In another
example, the two hosts may be two types of audio devices with
incompatible card slots. Other examples of uses of the daughter
memory card 11 with multiple hosts that accept incompatible cards,
as illustrated in FIG. 1, have already been discussed.
[0045] The separation of the memory card 11 from an existing card
has uses beyond the transfer of data between incompatible mother
cards. Even when only one host device is being used, or when two or
more host devices have card slots according to a single standard,
use of the separate memory card reduces the cost of storage for the
user. A single mother card containing the host interface circuits
and memory controller allows storage in a large number of less
expensive memory cards 11. These memory cards may even be
considered expendable and may be discarded after one or more uses,
much like a consumable razor blade where the controller and host
interface unit function analogous to a razor. The controller and
host interface unit needs to be purchased only once for a given
host device, in the form of a mother card, rather than having to
purchase the unit as part of every memory card, as is currently the
case with the memory cards discussed in the Background above.
[0046] The electronic functions of the host and cards are generally
illustrated in FIG. 2. An individual host 41 includes a connector
43 to which a card interface circuit 45 and power circuit 47 are
connected. The power circuit 47 provides the voltage(s) necessary
to operate the cards connected with the host. The interface circuit
45 passes data and commands between the host and the cards with a
particular protocol for a connected card. A mother card 49 includes
a first connector 51 that physically and electrically mates with
the host connector 43. Power received from the host, in addition to
being used by the various circuits of the mother card 49, is
received by a power circuit 53 that generates the voltages required
to operate memory circuits within a memory daughter card 55. The
mother card normally receives a low voltage from the host, such as
1.8 volts d.c., while memory arrays employed on daughter card 55
may over time employ different voltages and may require voltages
higher or lower than those supplied by the host; even higher
voltages may be required if the memory is a type that can be
programmed more than once, such as a flash EEPROM. The power
circuit 53 provides these voltages, usually by use of one or more
charge pumps or voltage conversion circuits, to a connector 57 that
mates with a connector 59 of the memory card 55. In this way the
mother card can interface with daughter cards of different
generations or of different memory technologies, possibly from
different manufacturers, that may require different voltages. This
requires that the daughter card provide to the mother card the
necessary information for power circuits 53 to provide the
appropriate voltages.
[0047] The mother card 49 also includes circuits 61 connected to
the connector 51 to interface data and commands with the host. A
programmable memory controller 63 is also included, often with a
general-purpose microprocessor/microcontroller 65, to manage the
memory within the card 55. The memory is provided within the card
55 by one or more integrated circuit memory chips 67. In order to
minimize the cost of the daughter memory card 55, each such chip
includes as few circuits as possible in addition to an array of
memory storage cells. The physical and electrical interface at
connector 57 is the same for all the different types of mother
cards, so the programmable controller 63 is much the same. The
physical and electrical interface at the mother card connector 51,
on the other hand, is likely different for each type of mother
card, as are the host interface circuits 61. The mother card
interface follows a standard such as one of the existing standards
described above in the Background. A number of such mother cards
that satisfy different ones of the standards are contemplated.
[0048] As much of the memory control, addressing, programming, and
reading circuits as practical are included within the mother card
49, rather than in the daughter memory card 55, in order to
minimize the size and cost of the daughter memory card. Preferably,
any circuits that work with the mother card
microprocessor/microcontroller 65 to carry out memory controlling
functions are included within the mother card 49. If a commercially
available flash EEPROM integrated circuit chip 67 is used, some
controlling functions are likely included in the memory chip such
as state machine controlled programming, reading and erasing
sequences. But the initiation and general control of such sequences
are typically handled by the microprocessor/microcontroller 65 that
executes firmware stored in a small code store (that can be ROM,
SRAM, flash memory, or other code storing memory not shown) on the
mother card. The daughter card may also contain all or part of this
firmware (typically in a write protected area) and the
microprocessor/microcontroller 65 may execute directly from this
address space, or the firmware may be transferred from the daughter
card 55 to a region of the code store on the mother card 49.
Further, the microprocessor/microcontroller 65 preferably performs
conversions of logical addresses received from the host into
physical addresses within the memory chip 67, reassigns memory
blocks such as may become necessary to avoid defective or overused
blocks, performs background operations such as re-programming to
restore margins between memory states (scrubbing) and compaction of
data pages stored in large blocks (garbage collection), and similar
types of functions where some level of intelligence is
required.
[0049] A suitable memory chip 67 is commercially available from
SanDisk Corporation or other companies. An example is a 512
mega-bit flash memory chip such as described in the "512 Mbit NAND
Flash Product Manual," revision 1.5, August 2001, available from
SanDisk Corporation, which Manual is hereby incorporated herein by
this reference. More than one such chip may be included in the
daughter card 55. This memory chip is of a type allowing a large
number of re-programming cycles in order to serve as computer mass
storage in place of a conventional magnetic disk drive system.
However, a less expensive flash EEPROM integrated circuit chip or
other programmable memory chip such as mask ROM, one time
programmable ROM, Ferroelectric RAM, Ovonic RAM, Polymeric RAM,
Magnetoelectronic RAM, fuse RAM, or other forms of memory may be
used instead if intended for an application requiring programming
only once or just a few times. Such applications include the
personal storage for archival or playback only of audio data, such
as music, and video data, such as still photographs. If the
daughter memory cards are made to be inexpensive enough, consumers
can record such data once and then store the card away. The cost of
a memory chip can be reduced when a large number of program/erase
cycles are unnecessary. Such alternative memory chips can utilize
either standard floating gates, dielectric layers, or programmable
fuses as storage elements of its memory cells. It should be clear
to the reader that the broad usage of different memory technologies
and architectures in the daughter card inevitably will require
different program/erase/read/file management/security algorithms
and different voltage/power conditions for each of these different
cards. Consequently the mother card must be able to supply such
algorithms and operating conditions for the various daughter cards,
and thus each daughter card must contain its specific and unique
operating conditions and communicate these to the mother card upon
request. This will advantageously be performed during
initialization (boot-up) of the daughter card after it is inserted
into and detected by the mother card.
[0050] It is also desirable to provide for the ability to use
different forms of the memory chip 67 that may require the mother
programmable controller card 49 to operate differently to control
operation of the memory. Among the memory chip differences that may
exist are binary (two-state) vs. multi-state (more than two state)
cell operation, the memory cell erase block size, the amount of
data that is programmed at one time, operating voltage(s) and
algorithms for programming data, reading data, erasing blocks and
performing error correction. If data stored on the daughter card
are to be protected from copying, then specific algorithms for
encryption or data protection may also be included together with
their requirements for reserved blocks of memory. Data of such
operating parameters may be stored in a portion of the memory
chip(s) 67 that is not accessible to a host system but which is
accessible by the memory controller 63. The memory controller of
the mother card 49 then reads this operating parameter data from
the memory chip(s) 67 upon initialization of the memory system
and/or when a new memory card 55 is connected with the mother card
49. The read data then causes the memory controller to adapt to the
operating parameters of the memory chip(s). This feature is also
useful for allowing use of future improved or changed memory chips
that may have such parameters changed.
[0051] During initialization it is a requirement that the memory
controller 63 be able to communicate with the memory IC chip 67 at
least to determine its operating parameters (voltage and
communication protocol). Thus a standardized method of initial
communication is defined, such as requiring all memory chips to
communicate using at least one fixed voltage supplied by the power
chip 53 and with a common signal format. For example, if all memory
chips are required to communicate at 1.8 volts and subsequently
identify that they need for example 3.0 volts (or 0.9 volt) for
full operation, the mother controller card can then instruct its
power unit to supply such voltage to facilitate further
communication. Alternately, one or more dedicated pins may be
included on the memory sub-card which the controller can
interrogate to determine the required communication voltage range.
After establishing initial communication, the other parameters
required to transfer data may be determined. The MMC.TM.
specification referenced previously describes one approach toward
meeting these requirements.
[0052] A simplified approach for initialization is described in the
following procedure. Upon application of power, the microprocessor
or microcontroller on the mother card initializes itself and begins
to monitor the card detect function described in detail below. Once
a daughter card is detected, the mother card communicates with it
using standardized protocol, timing, and voltage levels described
above (for example, 1 MHz clock rates and 1.8 volt operation). A
reserved sector located in a predefined location of the daughter
card is then read which contains various other parameters needed
for full operation of the daughter card. Such information includes
the data format of the stored data (sector size and how to find the
next sector), perhaps a file allocation table, maximum clock rates,
unique card identification data (including security features), and
information on required externally supplied voltages and timings
and algorithms for write or erase. After the reserved sector is
read and processed by the mother card, data communication between
the mother and daughter cards can occur.
[0053] As mentioned earlier, some applications require restricted
access to the content stored on the daughter memory card. This may
be accomplished in a variety of ways. One approach using the
ISO/IEC 7816 protocol is described below in conjunction with
various embodiments in which the daughter memory card includes
contacts to communicate using at least this protocol. Alternately,
the daughter memory card may be designed to prevent transmission of
data stored in certain predefined memory regions unless the mother
memory card (or memory controller embedded in a host system)
completes an authentication procedure to identify itself as
authorized to access such data. Such protected data may include,
for example, keys needed to decrypt content data stored in an
otherwise accessible region of the memory card, or the ability to
overwrite a lock protection feature restricting the ability of the
memory card to accept new data or overwrite existing data.
[0054] Referring to FIG. 3, a storage card 71, about the size of a
standard credit card, holds one or more daughter memory cards 11-1
through 11-5 in a manner that allows their easy removal and
replacement, for the purpose of transport or storage of the memory
card(s). The memory card(s) 11 may be positioned along one or more
edges of the storage card 71. Although the card 71 is preferably
made of thin, glossy plastic, like a standard credit card, a large
surface area 73 adjacent the attached memory card 11 is coated with
a material that accepts writing in pen or pencil. A user may then
store a particular memory card 11 having a set of photographs,
music or other data programmed thereon that is desired to be
retained. The nature of the data can then be written by the user in
the area 73. If a large number of memory chips are stored in this
way, one memory chip per storage card, they may be organized and
arranged, and desired data retrieved, by the information written
into several areas 73 on each storage card.
[0055] As an example, the storage card 71 is rectangular in shape,
with a length between 5 and 12 cm. and a width between 3 and 9 cm.
It is preferable that the card be made thin but thick enough so
that it is reasonably rigid, such as between 0.6 and 3 mm. in
thickness. Exposed contacts 75 may optionally be included on a
surface of the storage card 71 and connected to contacts 33 and 35
of memory cards 11-1 to 11-5 attached to it by conductors and
connectors (not shown) that are formed as part of the storage card
but this necessarily results in the card having a thickness
sufficient to accommodate the conductive lines and additional
insulation layers, as well as the respective connecting pins to
each of the contacts on the daughter cards 11-1 to 11-5. A decoding
integrated circuit (not shown) may also be included on storage card
71 to reduce the number of conductors while uniquely selecting one
of several daughter cards 11-1 through 11-5. This allows data to be
accessed on the several memory cards 11 without having to detach
them from the storage card 71. A card reader 77, having a
receptacle 79 for receiving the storage card 71, also includes the
functions of the mother card 49 of FIG. 2. Contacts 81 of the card
reader 77 correspond to the connector 57 of FIG. 2. The conductors
of the other connector 51 are connected to a host utilization
device 83, such as a personal computer. This allows, for example,
the user to conveniently view photographs or listen to music stored
on the several memory cards 11 by connection to a home computer
without having to detach the memory card 11 from the storage card
71.
[0056] Alternately the storage card 71 may have embedded into it a
controller chip that may provide the functionality of the mother
card controller 49 of FIG. 2, so that it can directly communicate
with each of the daughter cards 11. Such a storage card controller
chip or dedicated circuits can also provide smart card security for
accessing information on the daughter cards only by authorized
users. It can also provide communication from the storage card by
the ISO 7816 contactless or wireless protocol.
[0057] In the case where an embedded controller chip supports a
suitable protocol for connecting to the utilization device 83, the
storage card is acting as both a memory card controller and a
reader. Although any one of a variety of communication protocols
may be chosen, the USB protocol or IEEE 1394 ("Firewire") are
particularly attractive for communication to a personal computer
(PC). Other protocols such as ISO/IEC 7816, contactless, radio
frequency wireless (such as BlueTooth or 802.11) may also be
embedded in the storage card 71. In this case, the card reader 77
may be simply a mechanical adaptor and contain minimal or no active
circuitry.
[0058] FIG. 4 illustrates handling of the memory card 11, when
carried by the storage card 71, as the storage media for
photographs taken by a digital camera 85. The camera 85 is of a
type currently in widespread use that accepts CompactFlash.TM.
memory cards as the camera's "film." Therefore, the mother card 13
(FIG. 1) is used instead of the CompactFlash.TM. card, along with
the separate daughter memory card 11 that connects with the mother
card 13. The sequence of events for loading the camera 85 with the
memory card 11 are illustrated in FIG. 4 as follows: The memory
card 11 is removed from its storage card 71 and inserted into the
mother card 13, followed by inserting the mother card 13 into the
camera 85 in the same manner as a CompactFlash.TM. card would
normally be inserted. After data of photographs are stored on the
memory card 11, the reverse takes place: The mother card 13 is
removed from the camera 85, the memory card 11 then removed from
the mother card 13 and the memory card 11 is returned to the
storage card 71.
[0059] FIG. 5 illustrates another example use of the mother card,
where the memory controller of the mother card is integrated as a
permanent part of a different type of camera 87. In this case, the
memory card 11 is removed from the storage card 71 and installed
directly into the camera 87. After photographs have been taken, the
memory card 11 is removed from the camera 87 and returned to the
storage card 71. This system has the advantage of eliminating the
need for mother cards but requires a digital camera to include the
controller function before the memory card 11 can be used directly.
Even without mother cards being necessary for using the memory card
11 with the camera 87, a mother card would be necessary for the
memory card 11 to be used with other hosts that do not have the
memory controller built in. It should be evident to the reader that
although a camera is illustrated as the host which containing
suitable circuitry to support the daughter card directly, other
host devices are certainly possible such as cell phones or PDA's.
In this case it may be desirable to record information created or
downloaded by these hosts and transfer it to another host for later
review or modification. Examples include music or other audio files
(dictation, etc.), video images created by computer programs
initiated by the user, or data downloaded by the host using the
Internet.
[0060] A more detailed example of a daughter memory card is shown
in FIGS. 6A (plan view) and 6B (cross-sectional view) that also
includes the function of a security device. Physically, the outside
of the card is made to be the same as the Plug-in SIM card
discussed above in the Background. The electrical contacts (FIG.
6A) are arranged in an appropriate pattern across a surface of the
card, one such pattern being illustrated by way of example.
Contacts C1-C8 (121-129) follow the physical specification of the
ISO/IEC 7816 standard discussed above in the Background. Contacts
C1, C2, C3, C5, C6 and C7 are connected with a security integrated
circuit chip 89 (FIG. 7) within the daughter card, while the
standard leaves contacts C4 and C8 for future use. The chip 89 can
be the same chip that is currently used in Plug-in SIM cards, such
integrated circuit chips are available from Infinion, Hitachi,
STMicroelectronics, or GemPlus. A necessary number of additional
contacts 91-106 are added for connection to a mass memory
integrated circuit chip 90 that is also included in the daughter
card. The memory circuit chip 90 can be the 512 Mbit NAND chip
mentioned above or other suitable commercially available chip.
Multiple such chips (possibly stacked on each other) may be
included in the daughter memory card. Certain ones of the contacts
C1-C8 are multiplexed to also be used for the contacting pins of
the memory chip. Contact C1, designated by the ISO/IEC 7816
standard to receive a supply voltage VCC, the contact C5,
designated to be connected to ground, and the contact C6, to which
a variable programming voltage is applied, can likely be used by
both of the chips 89 and 90. The contacts C2 (reset signal), C3
(clock signal) and C7 (data input/output) can possibly be used by
both chips. The contacts that can be used by both chips are
connected within the card to both chips. Since the contacts C4 and
C8 are not currently used for the security chip 89, they can be
used for the memory chip 90. Other patterns of contacts are
certainly possible so long as metal is positioned in the regions of
the contacts C1-C3 and C5-C7 and connected with the security chip
89, if the card is to be compatible with the Plug-in SIM card
standard.
[0061] Referring to the cross-sectional view of FIG. 6B, the
daughter memory card includes a rigid substrate 109 to which the
external contacts are attached. One side of chip 90 is attached to
a top surface of the substrate 109 by an appropriate layer 111 of
adhesive. The chip 89 is attached to an opposite side of the chip
90 by another layer 113 of adhesive. Wire leads are connected
between pads of these chips to conductive traces (not shown) on the
top surface of the substrate 109, which in turn are connected
through conductive traces and vias (not shown) within the substrate
to the contacts on the outside of the package. Pads on the two
chips can be connected to at least some of the same outside
contacts C1-C3 and C5-C7, such as the power contacts, that serve
the same function for both chips. The package is completed by an
appropriate resin or other encapsulant 115 that encases the two
chips and the bonded wire leads. It should be clear to the reader
that other methods of establishing electrical connectivity between
one or both of chips 90 and 89 and the external contact surface of
the daughter card are possible. For example, some or all the
contacting pads may be placed on the top surface or top and bottom
surfaces of substrate 109 or along one or two edges. For example,
in FIG. 6B sample contacts 145 and 146 are shown on the opposite
side of substrate 109.
[0062] FIG. 7 shows a base surface of a receptacle for the card of
FIGS. 6A and 6B. When only the function of a Plug-in SIM card is to
be used, only pins C1'-C3' (121'-122') and C5'-C7' (125'-127') are
provided for contacting respective card contacts C1-C3 and C5-C7
when the card is placed contact side down on the surface of FIG. 8.
The pins C1'-C3' and C5'-C7' are arranged in the same pattern as in
existing receptacles for Plug-in SIM cards, such as found in
cellular telephones. These 6 receptacle pins are then connected
with the chip 89 according to the ISO/IEC 7816 standard. If
connection with both of the chips 89 and 90 is desired, the full
array of conductive pins are provided across the base surface of
the receptacle. In either case, the receptacle bases of FIG. 7 may
be positioned at the bottom of a slot in a mother controller card,
or other devices, into which the card of FIGS. 6A and 6B is
inserted by sliding across the receptacle surface from one side, or
clicking into place by top-side insertion. Alternatively, the
surface of FIG. 7 may be open from the top, in which case the card
is dropped into it, followed by urging the card contacts against
the receptacle pins by closing a cover over the card, or by
providing other known holding mechanisms.
[0063] Another example daughter card receptacle is shown in FIG. 8.
A daughter card 61 mates with an exposed surface 62 of the mother
card or storage card 60. A suitable insertion guide is a chamfered
corner 63 such that the cards can only mate in one orientation. A
suitable rounded edge profile 64 is provided on the card 61 so
that, when forcibly seated into the receptacle having mating curved
sides, the cards are held securely together. A removal mechanism
may include a hole 65 through the mother or storage card body
through which a pencil or other pointed object 66 may be inserted
to dislodge the daughter card 61 from the receptacle.
Alternatively, an edge or corner of the daughter card may overhang
the mother or storage card, thereby allowing the use of a finger or
tool to dislodge the daughter memory card.
[0064] FIG. 9 shows a daughter memory card with an alternate
contact arrangement. In this case all contacts are on one surface
of the card allowing contact to a smaller receptacle inside the
mother card, storage card, or reader. Although FIG. 9 shows the
contacts positioned on one end (smaller edge), it will be
understood that the contacts may also be positioned along the side
(longer edge), or along the sidewalls of the daughter card.
[0065] FIGS. 11A, 11B and 11C shows by dashed hidden lines a
specific embodiment card of FIG. 9. The card is constructed from a
metallic leadframe 190 shaped by stamping, etching, or various
other techniques known to those skilled in the art into the pattern
shown. FIG. 10 shows the starting metallic leadframe (metal is
shown shaded), although several of these leadframes are commonly
attached together in a strip as one solid piece of metal for
economies of manufacturing. The memory die 191 is then attached to
the leadframe using epoxy or similar adhesive material and leads
are attached between pad openings on the die surface 192 to
suitable pad regions 193 on the leadframe 190 using standard
integrated circuit bonding techniques such as ultrasonic wire
bonding 194 although other techniques such as plated bumps are
certainly possible. The leadframe is then formed using standard
techniques such that the external contacts 195 may be on a
different plane than the interconnection portion of the leadframe.
The card is then molded with a suitable encapsulate material 199 to
mechanically protect the memory die 191 and the leadframe. The
leadframe is cut along the trim lines 188 and 189 (FIG. 10) to
electrically isolate the leads, either before the forming operation
or after the molding operation, and the outer portions of the
original leadframe are discarded, leaving the metal portions shown
in FIGS. 11A-C.
[0066] The uniqueness of this leadframe design is that bonding pads
on one or more sides of the memory die can be routed through the
leadframe pattern to one or more different sides of the package,
similar to a printed circuit board pattern. However, for this
application the advantages of a leadframe over a printed circuit
board include lower cost and reduced card thickness. The only
wiring restriction is the inability to cross traces using only one
level of leadframe interconnection, although this restriction is
identical to that in common use today in matching any integrated
circuit die into a suitable package; in practice die pad locations
and package pin locations are considered together during the design
phase of an integrated circuit. In prior art technology die are
attached to a solid paddle region on the leadframe which prevents
this wiring flexibility, but this embodiment allows more freedom in
routing die interconnections from existing die to different package
locations; specifically pads on two sides of a memory die may be
routed to one edge of the daughter card. This routing flexibility
occurs because the area under the memory die can be used for
routing interconnections. The die is attached directly to and
supported by (but electrically insulated from) the routing
interconnections rather than a paddle area as is usually used. The
leadframe 190 may then be formed using standard techniques to bring
the daughter card interconnection pad locations 193 to a different
vertical level than the bottom die surface (as shown in FIG. 11C),
and then plastic molded in conventional fashion to encapsulate the
die and leadframe, exposing only the card contact locations 195 of
the leadframe which in this example are exposed only on the top
surface along one edge of the daughter card similar to those shown
in FIG. 9.
[0067] Another example card structure is shown in FIGS. 12A, 12 B
and 12C, which correspond to respective FIGS. 11A, 11B and 11C,
wherein the same reference numbers are used for the same elements
and reference numbers with a prime (') indicate additional elements
corresponding to those identified by the reference number without
the prime. The primary difference between the two cards is the
attachment of a second memory or other integrated circuit die 191'
to a side of the leadframe conductors opposite to the die 191.
Wires 194' are attached between pads 192' of the memory die 191'
and the underside of appropriate conductors 190 of the leadframe
that may be in common with or separate from the leadframe
conductors 190 to which wires 194 are attached on their top
surfaces from pads 192 of the memory die 191. It is often desirable
that the second die be functionally identical to the first die yet
bond to substantially the same leadframe locations. This is
commonly accomplished by changing one or more masks during wafer
manufacture to alter the surface interconnection pattern from the
internal circuitry to the bond pads resulting in a second die whose
bond pads are in a mirror image location with respect to those on
the first die. In this example bond pad 192A on the top die 191 is
shown to bond to leadframe pad 193A and the corresponding pad on
the bottom die 191' bonds to leadframe pad 193B. If these two pads
perform an enable function for their respective chips 191 and 191',
selecting only one of the two external contacts 195 of the
leadframe conductors 193A and 193B will cause the other unselected
die to both ignore all other inputs and disconnect its outputs,
thus avoiding contention between the two die and allowing them to
share common leadframe conductors and external card contacts 195.
Security for access to the card can be provided by one of the die
191 or 191'. Security for access to the card can be provided by one
of the die 191 or 191'.
[0068] In a practical implementation of a removable card there are
certain mechanical details that become important such as ease of
proper card insertion, detection of a properly seated card,
securely retaining the card while inserted, and ease of card
removal. These are addressed in the designs shown in FIGS. 11A-C
and FIGS. 12A-C, where provision is made during the molding process
for guide slots 198 in the daughter card matching guide bars on the
mother card that work to assist the user in maintaining planarity
during insertion and prevent insertion in a manner that would not
make proper electrical contact. Once inserted, the mother card may
contain a suitable spring loaded lock mechanism that matches a
suitable detent 196 also formed during the molding process on the
card and securely holds the daughter card inside the mother card
ensuring continuous electrical contact. An ejection slot 197 may
also be included on the daughter card for ease of removal. In this
case an elongated slot is shown which can be utilized using a
fingernail or other suitable mechanical object such as a pencil to
overcome the spring loaded detent and eject the card.
Alternatively, the card of FIGS. 11A-C may be given the curved edge
shape of the card 61 in FIG. 8 for removably fitting into a
receptacle of the mother and storage cards having mating edge
shapes.
[0069] Detection of a properly inserted card is typically
accomplished by the mother card using a variety of techniques. One
approach is for the physical presence of a card to move a
mechanical switch, opening a dedicated circuit causing an interrupt
of the microprocessor or microcontroller on the mother card.
Another approach to card detection is for the daughter card to
contain a short between two otherwise insulating pins on the mother
card interface connector such that current flows upon insertion.
The card detection process then causes the mother card to initiate
an initiation process to determine how to communicate with the
daughter card.
[0070] An alternative to the storage card 71 of FIG. 3 is
illustrated in FIG. 13. A storage card 151 has daughter memory
cards 153 and 154 removably attached to it and an area 155 with a
surface upon which the user may make a record 157 of the contents
of the attached memory cards by handwriting with a pen or a pencil.
The size of the storage card 151 is most conveniently that of a
Smart Card (ID-1 SIM described above in the Background). The memory
card 153 is most conveniently the size of the Plug-in SIM card and
positioned on the surface of the storage card 151 according to
Annex A of the GSM 11.11 specification previously discussed in the
Background. The memory card 153 is attached to the storage card 151
with its surface contacts (not shown) facing outward. These
contacts can have a pattern of those of the card of FIGS. 6A and
6B, FIG. 9 or some other pattern.
[0071] The memory card 153 can then be easily accessed while
attached to the storage card 151. A card reader, such as that shown
in FIG. 3, may include a receptacle that accepts the storage card
151 and with a mating pattern of elements to that of the contacts
of the memory card 153 so that, when the storage card 151 is
positioned in the card reader receptacle, an electrical connection
is made directly with the memory card surface contacts. This is
similar to a card reader for a Smart Card. The additional edge
connector and internal wire traces of the card 71 (FIG. 3) are then
unnecessary. Such a modified card reader is connected to a suitable
utilization device 83 in place of the card reader 77.
[0072] FIG. 14 shows a variation of the memory card of FIGS. 6A and
6B. A set of 22 contacts of the FIG. 14 card corresponds to those
of the card of FIGS. 6A and 6B, except that they are made shorter
in order to increase the space between them so that another
conductor 161 can be added to the card surface that extends along
the length of the card. The 22 contacts can serve in the same
manner as those of the card of FIGS. 6A and 6B. The added conductor
161 can be formed from the same layer of metal as the other 22
contacts. The conductor 161 provides, in this example, a radio
frequency antenna. A transceiver analog circuit is included within
the card and connected to this antenna. The card can then serve as
a radio frequency identification (RFID) tag. The analog circuit may
be integrated onto one of the chips 89 or 90 (FIG. 6B) within the
card, or may be in the form of an additional integrated circuit
chip.
[0073] The analog circuit receives its operating energy through the
antenna 161 from a nearby external radio frequency (r.f.) source,
typically one that is from 10 cm to 10 meters away, depending on
the frequency used. A small amount of non-volatile memory within
the analog circuit, typically for 128 bits of data, stores a user's
unique key, a unique manufacturer's card number, or some other
code. This data is read when the circuit is powered up by the
external r.f. source, and then transmitted back through the antenna
161. An external r.f. receiver, which can be integrated with the
r.f. transmitter, then reads the transmitted code. The flash memory
and security chips within the memory package are not activated
during this operation since the required voltage supply is not
connected with the external contacts of the memory card.
[0074] One application of providing the RFID tag within a memory
card is for theft protection. In a retail store, for example, a
cashier can activate operation of this memory after payment for the
memory card has been received from the customer, by storing a
unique code or otherwise. Any inactivated card will trip an alarm
when passing through a store exit equipped with the r.f.
transmitter and receiver.
[0075] The analog circuit can also be used to enable operation of
the flash memory within the same card only when the code memory is
activated. Thus, a memory card not activated by the sales clerk at
the point of sale will not operate. Further, the RFID tag feature
can also be used as a limited form of protected storage for a user
key as an alternative to use of the security chip 89 (FIG. 6B).
[0076] Another application is for inventory control of the memory
cards. A unique code stored by the manufacturer can be used for
this. Cards being received into inventory are passed by the r.f.
transmitter and receiver to read this code, which is then stored in
an inventory control database. When a card is removed from
inventory, the code is again read and so noted in the inventory
database.
[0077] Alternately, the RFID function may be incorporated into the
storage card 71 of FIG. 3 containing an embedded controller. In
this case the RF signal supplies both the desired data and a source
of power to energize the embedded controller. The controller in
turn can interrogate each of the attached memory daughter cards and
determine if any of them satisfy the desired criteria. The result
is that the desired data can be located from a collection of
storage cards containing a collection of attached memory cards
without inserting each storage card sequentially into a reader.
This embodiment can be particularly useful when multiple daughter
cards included in a storage card contain numerous images or
numerous recorded songs and it is useful to create an electronic
photo album or a music library through the RFID function
interrogating each of the daughter cards and electronically
identifying which cards store which photographs or songs.
[0078] Although the present invention has been described through
exemplary embodiments thereof, it will be understood that the
invention is entitled to protection within the full scope of the
appended claims.
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