U.S. patent application number 11/513687 was filed with the patent office on 2008-03-06 for power supply capable of receiving digital communications from electronic devices.
Invention is credited to Frank Patrick Paniagua, Patrick Edward Weston.
Application Number | 20080059816 11/513687 |
Document ID | / |
Family ID | 39136809 |
Filed Date | 2008-03-06 |
United States Patent
Application |
20080059816 |
Kind Code |
A1 |
Paniagua; Frank Patrick ; et
al. |
March 6, 2008 |
Power supply capable of receiving digital communications from
electronic devices
Abstract
A power supply capable of receiving digital communications from
an electrical device is described. The power supply includes a
microprocessor and instructions, configured for execution by the
microprocessor, to receive a digital communication from a device to
be powered by the power supply. A method of supplying power is also
described. The method includes receiving a digital communication
from a device and supplying power to the device based on the
digital communication.
Inventors: |
Paniagua; Frank Patrick;
(San Ramon, CA) ; Weston; Patrick Edward; (Cameron
Park, CA) |
Correspondence
Address: |
MORGAN, LEWIS & BOCKIUS, LLP.
2 PALO ALTO SQUARE, 3000 EL CAMINO REAL
PALO ALTO
CA
94306
US
|
Family ID: |
39136809 |
Appl. No.: |
11/513687 |
Filed: |
August 30, 2006 |
Current U.S.
Class: |
713/300 |
Current CPC
Class: |
G06F 1/263 20130101;
G06F 1/26 20130101 |
Class at
Publication: |
713/300 |
International
Class: |
G06F 1/00 20060101
G06F001/00 |
Claims
1-53. (canceled)
54. A power supply comprising: an input port to receive power from
a power source; a regulator to convert the received power from the
power source; an output port configured to supply power from the
regulator to a device; and a microprocessor configured to
communicate digitally with the device to determine power
requirements of the device, wherein the regulator converts the
power from the power source in accordance with the power
requirements of the device.
55. The power supply according to claim 54, wherein the power
requirements include charging requirements for a battery disposed
in the device.
56. The power supply according to claim 54, wherein the power
requirements include one or more of: voltage, current, and wattage
values.
57. The power supply according to claim 54, wherein the power
requirements include at least a voltage value and a current
value.
58. The power supply according to claim 54, wherein the power
delivered to the device is DC.
59. The power supply according to claim 54, wherein the power
received from the power source is AC.
60. The power supply according to claim 54, wherein the power
received from the power source is DC.
61. The power supply according to claim 54, wherein the power
supply receives a communication from the device that includes one
or more of the following: power requirements, proprietary
information, and a battery ID of a battery disposed in the
device.
62. The power supply according to claim 54, wherein the regulator
is configured to deliver a predefined amount of power to the device
when the device is coupled to the output port to allow the power
supply to communicate with the device.
63. The power supply according to claim 54, wherein communicating
digitally includes using a packet layer protocol.
64. The power supply according to claim 63, wherein the packet
layer protocol includes at least four message types.
65. The power supply according to claim 64, wherein the messages
types include three flow control message types and a power
statement message type.
66. The power supply according to claim 63, wherein the packet
layer protocol includes a checksum.
67. The power supply according to claim 63, wherein the packet
layer protocol includes a payload segment.
68. The power supply according to claim 67, wherein the payload
segment includes proprietary information.
69. The power supply according to claim 67, wherein the payload
segment includes a client condition code segment.
70. The power supply according to claim 67, wherein the payload
segment includes a voltage segment.
71. The power supply according to claim 67, wherein the payload
segment includes a charger segment.
72. The power supply according to claim 67, wherein the payload
segment includes a power value segment.
73. The power supply according to claim 54, wherein the
microprocessor provides a power control signal to control the
regulator.
74. A method of supplying power to a device comprising the steps
of: receiving power from a power source; receiving a digital
communication from the device; determining the power requirements
of the device in accordance with the digital communication;
converting the power from the power source in accordance with the
power requirements of the device; and supplying power to the device
based at least in part on the power requirements of the device.
75. The method of supplying power according to claim 74, wherein
the digital communication includes the power requirements of the
device.
76. A power supply comprising: an input port to receive power from
a power source; one or more regulators to convert power from the
power source; a plurality of output ports configured to supply
power from the one or more regulators to a plurality of devices;
and a microprocessor configured to communicate digitally with a
respective device of the plurality of devices to determine the
power requirements of the respective device, wherein one of the one
or more regulators converts power from the power source in
accordance with the power requirements of the respective
device.
77. The power supply according to claim 76, wherein the power
requirements include charging requirements for a battery disposed
in the respective device.
78. The power supply according to claim 76, wherein the power
requirements include one or more of: voltage, current, and wattage
values.
79. The power supply according to claim 76, wherein the power
requirements include at least a voltage value and a current
value.
80. The power supply according to claim 76, wherein the power
delivered to the plurality of respective devices is DC.
81. The power supply according to claim 76, wherein the power
supply receives a communication from the respective device that
includes one or more of the following: power requirements,
proprietary information, and a battery ID of a battery disposed in
the respective device.
82. The power supply according to claim 76, wherein a voltage and a
current of a respective device is independent of voltages and
currents delivered to each of the other devices.
83. The power supply according to claim 76, wherein the
microprocessor is a microcontroller.
84. The power supply according to claim 76, wherein the one or more
regulators delivers a predefined voltage to the respective device
when the respective device is connected to one of the output ports
to allow the power supply to communicate with the respective
device.
85. The power supply according to claim 76, wherein communicating
digitally includes using a packet layer protocol.
86. The power supply according to claim 85, wherein the packet
layer protocol includes at least four message types.
87. The power supply according to claim 86, wherein the messages
types include three flow control message types and a power
statement message type.
88. The power supply according to claim 85, wherein the packet
layer protocol includes a checksum.
89. The power supply according to claim 85, wherein the packet
layer protocol includes a payload segment.
90. The power supply according to claim 89, wherein the payload
segment includes proprietary information.
91. The power supply according to claim 89, wherein the payload
segment includes a client condition code segment.
92. The power supply according to claim 89, wherein the payload
segment includes a voltage segment.
93. The power supply according to claim 89, wherein the payload
segment includes a charger segment.
94. The power supply according to claim 89, wherein the payload
segment includes a power value segment.
95. The power supply according to claim 76, wherein the
microprocessor produces a power control signal to the one or more
regulators to control the one or more regulators.
96. A method of supplying power to a plurality of devices
comprising the steps of: receiving power from a power source;
receiving a digital communication from a respective device of the
plurality of devices; determining the power requirements of the
respective device in accordance with the digital communication;
converting the power from the power source in accordance with the
power requirements of the respective device; and supplying power to
the respective device based at least in part on the the power
requirements of the respective device.
97. The method of supplying power according to claim 96, wherein
the supplying is based exclusively on the determined power
requirements.
98. A device comprising: a microprocessor configured to communicate
digitally with a power supply to communicate power requirements of
the device to the power supply; the power supply being external to
the device; and the power requirements including at least voltage
and current values.
99. The device of claim 98, wherein the power requirements include
a wattage value.
100. The device of claim 98 further comprising a rechargeable
battery.
101. The device of claim 100, wherein the microprocessor
communicates one or more of the following: power requirements of
the device, proprietary information, and battery ID.
102. The device of claim 98, wherein the microprocessor is a
microcontroller.
103. The device of claim 98, wherein communicating digitally
includes using a packet layer protocol.
104. The device according to claim 103, wherein the packet layer
protocol includes at least four message types.
105. The device according to claim 104, wherein the messages types
include three flow control message types and a power statement
message type.
106. The device according to claim 103, wherein the packet layer
protocol includes a checksum.
107. The device according to claim 103, wherein the packet layer
protocol includes a payload segment.
108. The device according to claim 107, wherein the payload segment
includes proprietary information.
109. The device according to claim 107, wherein the payload segment
includes a client condition code segment.
110. The device according to claim 107, wherein the payload segment
includes a voltage segment.
111. The device according to claim 107, wherein the payload segment
includes a charger segment.
112. The device according to claim 107, wherein the payload segment
includes a power value segment.
113. A method of receiving power from an external power supply
external to a device comprising the steps of: receiving an initial
predetermined voltage sufficient to enable communication between
the external power supply and the device; transmitting a digital
communication to the external power supply to communicate power
requirements of the device to the external power supply; and
receiving power supplied by the external power supply based on the
power requirements of the device, wherein the power requirements
include at least a voltage value and a current value.
114. The method of claim 113, wherein the power requirements
include a wattage value.
Description
TECHNICAL FIELD
[0001] The disclosed embodiments relate generally to power
supplies, and more particularly, to a power supply that is capable
of receiving digital communications from devices to be powered by
the power supply.
BACKGROUND
[0002] Consumer electronic devices are ubiquitous in the world we
live in today. From laptop computers and personal digital
assistants to multimedia players and mobile phones, people today
own a wide variety of electronic devices. These electronic devices
come with a wide variety of power supplies, sometimes referred to
as "wall warts," "power bricks," or "power adapters."
Unfortunately, these power supplies are often specific to the
device type, device manufacturer, and/or device product line, and
are therefore incompatible with each other. If user loses a power
supply for a device, the power supply of another device generally
cannot be used as a substitute. This causes many problems. Travel
is made more inconvenient by the prospect of having to bring
multiple power supplies for various portable devices. A device may
be damaged and/or its useful life shortened if the wrong power
supply is used. Furthermore, as devices become obsolete and are
discarded by users, the power supplies for the devices may be
discarded as well because users often do not have other devices
that are compatible with these power supplies.
[0003] Attempts have been made to resolve the problem associated
with incompatible power supplies. One attempt involves a common
power supply with a swappable interface between the power supply
and the device to be powered. An example of this attempt is iGo (a
trademark of Mobility Electronics, Inc.), which employs swappable
connector tips. However, this attempt does not adequately solve the
problems of incompatibility (the tips are still
device/manufacturer/product-line specific), damage to a device
caused by the use of the wrong tip, and waste caused by
obsolescence.
[0004] Accordingly, what is needed is a power supply that can be
used to power a wide variety of devices without resorting to
device-specific interfaces.
SUMMARY
[0005] The above deficiencies and other problems associated with
power supplies are reduced or eliminated by the disclosed power
supply and an electronic device that are capable of digital
communications with each other.
[0006] According to some embodiments, a power supply includes one
or more microprocessors, and one or more sets of instructions
configured for execution by the one or more microprocessors. The
one or more sets of instructions include instructions to receive a
digital communication from a device to be powered by the power
supply.
[0007] According to some embodiments, a power supply includes one
or more circuits for receiving a digital communication from a
device to be powered by said power supply.
[0008] According to some embodiments, a power supply includes means
for receiving a digital communication from a device, and means for
supplying power to said device based on said digital
communication.
[0009] According to some embodiments, a method of supplying power
includes receiving a digital communication from a device, and
supplying power to the device based on said digital
communication.
[0010] According to some embodiments, an electrical device includes
one or more microprocessors, and one or more sets of instructions
configured for execution by the one or more microprocessors. The
one or more sets of instructions include instructions to transmit a
digital communication to a power supply external to the electrical
device.
[0011] According to some embodiments, an electrical device includes
one or more circuits for transmitting a digital communication to an
external power supply.
[0012] According to some embodiments, an electrical device includes
means for transmitting a digital communication to an external power
supply, and means for receiving power supplied by the external
power supply based on the digital communication.
[0013] According to some embodiments, a method of receiving power
includes transmitting a digital communication to an external power
supply, and receiving power supplied by the external power supply
based on the digital communication.
[0014] According to some embodiments, a power supply includes one
or more circuits, means for receiving a digital communication, and
means for configuring, based on said digital communication, the one
or more circuits to supply a constant voltage or power conforming
to one or more battery type-dependent charging requirements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] For a better understanding of the aforementioned embodiments
of the invention as well as additional embodiments thereof,
reference should be made to the Description of Embodiments below,
in conjunction with the following drawings in which like reference
numerals refer to corresponding parts throughout the figures.
[0016] FIG. 1 is a block diagram illustrating a power supply
coupled to a power source and electronic devices in accordance with
some embodiments.
[0017] FIG. 2 is a block diagram illustrating a power supply
capable of receiving digital communications from devices in
accordance with some embodiments.
[0018] FIG. 3 is a block diagram illustrating a device capable of
sending digital communications to a power supply in accordance with
some embodiments.
[0019] FIG. 4 is a flow diagram illustrating a process of supplying
and receiving power in accordance with some embodiments.
[0020] FIGS. 5A-5B are diagrams illustrating a packet structure of
a digital communication between a power supply and a device in
accordance with some embodiments.
[0021] FIG. 6 is a state diagram illustrating digital communication
states of a power supply in accordance with some embodiments.
[0022] FIG. 7 is a state diagram illustrating digital communication
states of a device in accordance with some embodiments.
DESCRIPTION OF EMBODIMENTS
[0023] Reference will now be made in detail to embodiments,
examples of which are illustrated in the accompanying drawings. In
the following detailed description, numerous specific details are
set forth in order to provide a thorough understanding of the
present invention. However, it will be apparent to one of ordinary
skill in the art that the present invention may be practiced
without these specific details. In other instances, well-known
methods, procedures, components, and circuits have not been
described in detail so as not to unnecessarily obscure aspects of
the embodiments.
[0024] Attention is now directed to FIG. 1, which illustrates a
power supply coupled to a power source and devices in accordance
with some embodiments. A power supply 106 may be electrically
coupled to a power source 108, from which the power supply 106
receives electrical power to be supplied to devices 102. The power
source may be a source of alternating current (AC) or direct
current (DC) voltage. In some embodiments, the power source is a
power outlet, such as a wall outlet. The power outlet may provide
AC voltage, which is typically 110 V in the United States and may
be at other voltages outside the United States and/or depending
upon local requirements. In some other embodiments, the power
source is an outlet in an airplane armrest or in an automobile,
such as a cigarette lighter socket, which provides 12 V DC voltage.
In further other embodiments, the power source is a motor,
generator, battery, etc. that provides electricity. Depending on
the particular embodiment, the power supply 106 may be configured
for coupling to only a DC power source, only an AC power source, or
either a DC or AC power source. The power supply 106 may be coupled
to the power source 108 via a power cord, cable, or the like.
[0025] The power supply 106 may be electrically coupled to one or
more devices 102. The devices 102 may include any of a variety of
electronic devices, including but not limited to consumer
electronic devices, computer devices and peripherals (e.g., desktop
computers, laptop computers, printers, scanners, monitors, laptop
docking stations, etc.), small appliances, battery chargers, and
power tools. Depending on the particular embodiment, if there are
multiple devices 102 coupled to the power supply 106, the devices
102 may be coupled to the power supply 106 independently or in
series or in parallel.
[0026] In some embodiments, the power supply 106 is a standalone
unit, external to and distinct from devices to be powered by the
power supply 106. The external power supply 106 may be electrically
coupled to one or more devices via power cords, cables, or the like
(not shown). In some embodiments, both the power supply 106 and a
device 102-A conform to a common connector or interface standard;
the power cord coupling the power supply 106 to a given device,
such as the device 102-A includes standardized connectors on one or
both ends of the cord, and may, in some embodiments, be
non-detachably affixed to the power supply 106. A device may be
designed to use the standardized connector and be coupled to the
power supply via a cord having the standardized connectors. In
other words, the power supply serves as a universal power supply to
any device that is designed to include the standardized
connector.
[0027] In some other embodiments, the power supply 106 and a device
102-B use different types of power connectors. For example, a
device that is not designed to use the standardized connector
(e.g., an older device) may have a power connector that is device
or manufacturer specific and not conforming to the standard that is
used by the power supply 106. In such embodiments, the power supply
106 may be coupled directly to the device 102-B via a cord that
includes the standardized connector on one end and a device or
manufacturer specific connector on the other end. In other words,
the cord is customized to the connector on the device because at
least one connector on the cord is device or manufacturer specific.
Alternatively, an attachment, such as a dongle, may be coupled to
the device 102-B. The attachment "converts" the connector on the
device 102-B to the standardized connector utilized by the power
supply 106, thereby allowing coupling of the power supply 106 and
the device 102-B via a cord having the standardized connector on
both ends. An example of such a connector converter 104 is shown in
FIG. 1.
[0028] In some other embodiments, the power supply 106 is
integrated with the device to be powered by the power supply. For
example, the power supply 106 may be the internal power supply of a
desktop computer, an audio/visual receiver or preamplifier, a power
strip or surge protector, an uninterruptible power supply, or
something similar. Furthermore, in some embodiments, other external
devices may be electrically coupled to a power supply 106 that is
integrated into another device. For example, returning to the
example of the power supply 106 integrated with a desktop computer,
other external devices, such as a monitor, printer, and scanner,
may be coupled to the power supply that is integrated with the
desktop computer. The integrated power supply supplies power to the
coupled external devices as well as the desktop computer.
[0029] The power supply 106 may come in a variety of sizes. For
example, the power supply 106 may be implemented in a relatively
small size for ease of portability and travel convenience.
Relatively larger power supplies 106 may be implemented for home,
office, or industrial use.
[0030] As described above, devices 102 that may be electrically
coupled to the power supply 106 may encompass a variety of
electronic devices, including but not limited to consumer
electronic devices (e.g., mobile phones, cordless phones, baby
monitors, televisions, digital cameras, camcorders, MP3 or video
players, CD or DVD players, VCRs, personal digital assistants
(PDAs)), computer devices (e.g., computers, network routers,
non-volatile storage, printers, monitors, scanners), small
appliances, battery chargers, and power tools. Some of these
devices may include a battery or batteries and some may not. The
battery (or batteries) may be rechargeable or non-rechargeable.
Examples of rechargeable battery technologies include lithium-ion
batteries, nickel cadmium batteries, and nickel metal hydride
batteries. Examples of non-rechargeable battery technologies
include alkaline and lithium batteries. For a device that does not
have a battery or that has non-rechargeable batteries, the power
supplied by the power supply 106 merely powers the device for
operation. For a device that has a rechargeable battery, the power
supplied by the power supply 106 powers the device for operation
and/or recharges the battery. As it is known in the art, different
devices and batteries have different power requirements for
operation and/or battery charging. Thus, the power supply 106 needs
to know the power requirements of the devices 102, in order to
supply the proper amount of power.
[0031] Attention is now directed to FIGS. 2-3, which are block
diagrams illustrating a power supply 200 capable of receiving
digital communications from electronic devices and a device 202
capable of sending digital communications to a power supply in
accordance with some embodiments. The power supply 200 acquires
information regarding power requirements of a device 202 to be
powered by the power supply 200 via digital communications between
the power supply 200 and the device 202. Based on the information,
the power supply may supply power to the devices 202 in accordance
with the power requirements of the devices 202.
[0032] A power supply 200 may receive either a DC input voltage
(e.g., 12 V from an automobile cigar lighter socket) or an AC input
voltage (e.g., 110 V or a 220 V from a wall outlet) from a power
source 108. Either input voltage may be fed through surge
protection circuitry/components 204 in the power supply 200. The
(optional) surge protection circuitry or components, which are well
known in the art, may be included in the power supply 200 for
protection against power surges or electrical spikes. Voltage from
an AC source may also be fed through an AC/DC converter 206. The
AC/DC converter 206 converts voltage from the AC source to a DC
voltage for use by devices 202.
[0033] The electrical power may be fed from the surge protection
circuitry 204 or the AC/DC converter 206, through an electrical bus
208, to various circuitries within the power supply 200. The
circuitries within the power supply 200 may include a circuitry 210
for supplying a predefined voltage and one or more programmable
regulators 212. In some embodiments, the predefined voltage
circuitry 210 supplies a predefined "wake-up" voltage to the
devices 202. In some embodiments, the predefined voltage is +5 V.
The "wake-up" voltage may facilitate the powering-on of a device
202 and/or digital communications between the device 202 and the
power supply 200. The "wake-up" voltage may be provided to the
device 202 via a predefined voltage line 214 that is electrically
coupled to a microprocessor 302 within the device. The "wake-up"
voltage powers the device microprocessor 302, facilitating the
microprocessor 302 to execute instructions to send digital
communications containing power requirements to the power supply
200 on the communications line 218.
[0034] One or more programmable regulators 212 supply power to a
device 202, via one or more supply conductor lines 224. The power
supplied by a programmable regulator 212 may be in the form of a
constant voltage and/or a constant current. In some embodiments,
there may be two or more regulators 212: at least one regulator
212-A that is coupled to a power management circuitry 304 of the
device 202 via a supply conductor line 224-A and is responsible for
supplying a constant voltage for powering the device 202, and at
least one regulator 212-B that is electrically coupled to a battery
306 of to the device 202 via a supply conductor lines 224-B and is
responsible for supplying a constant current for charging the
battery 302. In some other embodiments, there may be one regulator
212 that is responsible for supplying a constant voltage or a
constant current. In some embodiments, the programmable regulator
212 is a programmable switching regulator. In some other
embodiments, the programmable regulator 212 is a programmable
linear regulator.
[0035] Programmable power supplies are well known in the art.
Generally, these are digitally controlled power sources that can
provide adjustable output values, e.g., voltage or current, through
the use of feedback circuitry and a digital reference value. For
example, after a digital reference value is specified, if the
output voltage is too low a controlling element is instructed to
produce a higher voltage. Conversely, if the output voltage is
higher than the specified digital reference value, the controlling
element is instructed to produce a lower voltage. Furthermore,
those skilled in the art will recognize the use and application of
linear or switching regulators in programmable power supplies.
[0036] The regulator(s) 212 supply power to devices 202 in
accordance with one or more provided parameters. In some
embodiments, the one or more parameters provided to the
regulator(s) 212 may include an amount of voltage, current, and/or
wattage to be supplied to the device. In other embodiments, the
parameters may also include an identifier related to the device. In
some embodiments, this identifier provides a mechanism to validate
or track licenses. In other embodiments, this identifier enables an
original equipment manufacturer ("OEM") to implement one or more
proprietary functions related to a device and may also enable the
transmission of proprietary information between the device and the
power supply. For example, where the identifier of a rechargeable
battery indicates that it is from the same manufacturer as the
power supply, additional proprietary information, such as the total
number of charge cycles of the battery, may be passed to the power
supply. By way of further example, where the identifier indicates
the same OEM, enhanced or alternate functions may be available,
which may affect the behavior of the power supply in order to
remain in compliance with the specifications of the manufacturer.
In other words, the provided parameters configure or "program" the
programmable regulator(s) 212 to supply power that conform to the
power requirements of a device 202 to the device 202. The
parameters may be provided to the programmable regulator(s) 212 via
a data bus 216 by a microprocessor 222.
[0037] The power supply 200 includes one or more microprocessors
222. The microprocessor 222 sends and receives digital
communications from devices 202 and configures the programmable
regulators 212 by providing parameters such as voltage and current
values. The microprocessor 222 sends and receives digital
communication from devices 202 via a communications bus 218. The
microprocessor 222 receives and processes digital messages from the
devices 202. In some embodiments, the processing of a digital
message from a device 202 includes error detection, inspecting the
contents of the message, and based on the contents, execute further
instructions. Based on the content of the messages, the
microprocessor 222 executes instructions to send responses to the
devices 202 via the communications bus 218 and/or provide voltage
or current values to the programmable regulators 212.
[0038] In some embodiments, the microprocessor 222 is coupled to a
memory 220. Memory 220 may include non-volatile memory such as a
hard disk drive or flash memory. In some embodiments,
microprocessor 222 is integrated on the same die as memory 220.
Memory 220 may store data that the microprocessor 222 may reference
in the process of communicating with the devices 202 and
configuring the programmable regulators 212.
[0039] In some embodiments, memory 220 stores a database of
predefined power profiles. A power profile is a predefined set of
data that specifies power requirements, or more particularly, a
predefined combination of power requirement parameters. In some
embodiments, a power profile includes one or more of the following:
a constant voltage value, a constant current value, a wattage
value, an upper limit current value, and a battery type. The power
profiles may be organized as a lookup table in memory 220, with
each power profile referenced by an identifier. A device 202 may
communicate, in a digital message, the identifier of the desired
profile to the microprocessor 222. The microprocessor 222 retrieves
from memory 220 the power profile corresponding to the identifier
provided by the device 202. Parameters in the retrieved power
profile are used to configure the programmable regulators 212.
[0040] In some other embodiments, memory 220 stores a database of
battery information. The database of battery information is similar
to the database of power profiles described above; the database of
battery information includes predefined sets of power requirement
parameters for batteries. As with the power profile database, the
battery information database may be organized as a lookup table.
The database may include sets of data that are specific to
particular models of batteries. The sets of data in the battery
information database may be associated with and identified by an
identifier such as a combination of a vendor/manufacturer
identifier and model number. The power requirement data sets for
batteries may include one or more of the following: a constant
voltage value, a constant current value, a wattage value, an upper
limit current value, a maximum charge duration, and a maximum
operational temperature during a charge cycle (which may be sensed
using a thermistor attached to the battery). Similar to the power
profiles described above, a device may communicate, in a digital
message, an identifier of a battery coupled to the device to the
microprocessor 222. The microprocessor 222 retrieves from memory
220 the power requirement data set corresponding to the battery
identifier provided by the device. Values in the retrieved power
requirement data set are used to configure the programmable
regulators 212. It should be appreciated, however, that memory 220
may include either or both of the power profile and battery
information databases.
[0041] In further other embodiments, memory 220 may include a
database of identifiers associated with known vendors of devices or
a database of identifiers of devices. Furthermore, in alternative
embodiments, the power supply 200 may omit memory 220 entirely. The
power supply 200 may accept messages from devices that specify the
actual power requirements but not messages identifying a power
profile or battery model. In such embodiments, the device 202 must
signal the power requirements directly and not rely on the power
supply 200 to determine the power requirements based on merely a
power profile identifier or a battery model identifier. In other
embodiments, battery database information or identifier database
information stored in memory 220 may be automatically updated when
an "unknown" device is identified by the power supply.
Additionally, in other embodiments, manual updating of database
information in memory 220 may occur.
[0042] In some embodiments, the power supply 200 and a device 202
may be coupled via additional lines. For example the power supply
200 and the device 202 may also be coupled by a battery thermistor
line. The thermistor aids in the monitoring of the temperature of a
battery coupled to the device 202 as a safeguard against
overheating of the battery. As another example, the power supply
200 and the device 202 may be coupled by a OV ground or signal
return line. In some embodiments, the lines 214, 218, 224, etc.
coupling the power supply 200 to a device 202 may be implemented as
conductive elements running within the power supply 200 or the
device 202 that terminate at a connector or interface that includes
a plurality of conductive pins terminals. The connector at the
power supply 200 and the connector at the device 202 may be coupled
by a cord or the like that has connectors on the ends that match
the connectors on the power supply 200 and the device 202 and has
distinct conductive elements (e.g., wires) within the cord
corresponding to each of the lines.
[0043] In some embodiments, a power supply 200 may be further
configured to receive messages containing proprietary information
from a device 202. A device may be configured by its manufacturer
to send a message that includes information other than those
described above, and a power supply made by or for the same
manufacturer may be configured to recognize the information. The
information may include data that are typically proprietary or
specific to devices of the same manufacturer such as battery
charging cycles or data for updating or reconfiguring the power
supply. Thus, manufacturers may provide a power supply that can
receive not only, from any device made by any manufacturer and
which conforms to the embodiments described above, generic power
requirement information, but also receive proprietary information
from devices made by the same manufacturer. In other words, a power
supply 200 can be configured to include both universal features and
proprietary features.
[0044] Attention is now directed to FIG. 4, which is a flow diagram
illustrating a process of supplying and receiving power in
accordance with some embodiments. When a device is first
electrically coupled to a power supply that is drawing power from a
power source, the device transmits a digital message to the power
supply (402). In some embodiments, the digital message includes the
power requirements of the device or an identifier of a power
profile or battery. The message is received by the power supply
(404) and processed by the power supply (406). The processing
includes determining the type of message, inspecting the contents
of the message, and, based on the contents, providing the proper
parameters to programmable regulators that control the amount of
voltage or current to be supplied to the device. If the contents
include an encoded statement of power requirements, the power
supply decodes the statement. If the payload includes an identifier
of a battery or a power profile, the power supply retrieves a data
set of power requirements associated with the identifier.
[0045] Power is supplied to the device based on the information in
the digital message (408). The power requirement parameters
included in the message or derived from information included in the
message are used to configure the power supply (or more
particularly, programmable regulators within the power supply) to
supply the proper voltage, current, and/or power to the device. The
power supplied by the power supply is received by the device (410).
The power received by the device may be used to power the device
for operation and/or charge a battery coupled to the device.
[0046] Attention is now directed to FIGS. 5A-5B, which are diagrams
illustrating a packet structure of a digital message that may be
exchanged between a power supply and a device in accordance with
some embodiments. The digital messages sent and received by the
power supply 200 and devices 202 may conform to a predefined
packet-based protocol. An exemplary digital message packet 500
includes a 1-byte transmission start segment 502 indicating the
start of the message, a 4-byte vendor/manufacturer identifier 504,
a 1-byte message type segment 506 indicating the type of message, a
variable size payload 508, a 2-byte checksum 510, and a 1-byte
transmission end segment 512 indicating the end of the packet. It
should be appreciated that the sizes of the packet segments
described above are merely exemplary and that alternate segment
sizes may be used. For example, the transmission start segment 502
and the transmission end segment 512 may each be less than 1 byte
long. As another example, the vendor/manufacturer identifier 504
may be 2 bytes rather than 4 bytes.
[0047] The checksum 510 is used for error detection. The checksum
510, as used herein, refers generally to any kind of redundancy
check for error detection. The checksum 510 may be implemented
using any of a variety of error detection technologies now known or
later developed, including but not limited to cyclic redundancy
checks, checksum algorithms, and hash functions.
[0048] In an exemplary embodiment, the protocol includes at least
four message types. The message types may include three flow
control message types and a power statement message type. The flow
control message types serve to signal success or error in the
receipt of messages. In some embodiments, the flow control message
types include the acknowledgement message (ACK), the
non-acknowledgement message (NACK), and the cancel message (CAN).
These messages are further described below, in relation to FIGS.
6-7. A power statement message type specifies the power
requirements of the device. In some embodiments, the power
statement includes, e.g., voltage, current, and/or battery type
parameters. In some other embodiments, the power statement includes
more or less parameters than described above. In further other
embodiments, the power statement includes an identifier of a power
profile or a battery model, with which a power supply having
databases of power profiles and/or battery information can look up
the corresponding power requirements. If a manufacturer wishes to
enable exchange of proprietary information via the digital
messages, a proprietary or manufacturer-specific message type may
also be included.
[0049] The payload 508 in the message 500 is the segment that holds
the data of interest. For flow control messages such as ACK, NACK,
and CAN, the payload 508 may be omitted (i.e., 0 bytes). For power
statement messages, the payload 508 may include the power
requirements information or information from which power
requirements may be identified. In an exemplary embodiment, the
payload 520 of a power statement message that specifies power
requirements for a device includes a client condition code segment
522, a voltage segment 524, a charger segment 526, and a power
value segment 528, further details of which are described below. In
an embodiment where the power supply can accept messages containing
proprietary information from the device, the payload 508 may
include the proprietary information structured in a
manufacturer-specified format and size.
[0050] The client condition code 522 may be an encoded segment that
provides information regarding general power parameters. In some
embodiments, the client condition code 522 provides information
regarding whether the desired voltage for the device is high power
or low power, whether the desired voltage for the device is
positive or negative, whether battery charging power is needed, and
the technology of the battery to be charged (e.g., lithium-ion,
nickel metal hydride, etc.). A table of an exemplary encoding of
the client condition code 522 is included below (the code uses the
lowest 5 bits of the byte; the other 3 bits in the byte may
reserved for future code expansion or left unused):
TABLE-US-00001 CCC Byte CHARGER VOLTAGE VOLTAGE Battery bit 4 bit 0
Power Polarity CHARGER technology 00000 Low Negative Off N/A 00001
High Negative Off N/A 00010 Low Positive Off N/A 00011 High
Positive Off N/A 00100 Low Negative On Li-Ion 00101 High Negative
On Li-Ion 00110 Low Positive On Li-Ion 00111 High Positive On
Li-Ion 01000 Low Negative Off N/A 01001 High Negative Off N/A 01010
Low Positive Off N/A 01011 High Positive Off N/A 01100 Low Negative
On Li-Poly 01101 High Negative On Li-Poly 01110 Low Positive On
Li-Poly 01111 High Positive On Li-Poly 10000 Low Negative Off N/A
10001 High Negative Off N/A 10010 Low Positive Off N/A 10011 High
Positive Off N/A 10100 Low Negative On Ni-CD 10101 High Negative On
Ni-CD 10110 Low Positive On Ni-CD 10111 High Positive On Ni-CD
11000 Low Negative Off N/A 11001 High Negative Off N/A 11010 Low
Positive Off N/A 11011 High Positive Off N/A 11100 Low Negative On
Ni-MH 11101 High Negative On Ni-MH 11110 Low Positive On Ni-MH
11111 High Positive On Ni-MH
[0051] The voltage segment 524 is an encoded segment that specifies
the desired output voltage and upper limit current to be supplied
by the power supply. The charger segment 526 specifies the number
of cells in the battery or batteries to be charged and the desired
current value for charging the battery or batteries of the device.
A table of an exemplary encoding of the voltage segment 524 and the
charger segment 526 is included below (the code uses the lowest 5
bits of each byte; the other 3 bits in each byte may be reserved
for future code expansion or left unused):
TABLE-US-00002 VOLTAGE VOLTAGE VOLTAGE VOLTAGE Byte 0 Byte 1 Byte 0
Byte 1 CHARGER CHARGER Low Power Low Power High Power High Power
Byte 0 Byte 1 bit 4 bit 0 Output Voltage Limit Current Output
Voltage Limit Current Number of Cells Charge Current 00000 0.0 0.0
0.0 0.0 0.00 0.00 00001 0.5 0.1 1.0 0.3 1.00 0.05 00010 1.0 0.1 2.0
0.6 2.00 0.10 00011 1.5 0.2 3.0 0.9 3.00 0.15 00100 2.0 0.2 4.0 1.2
4.00 0.20 00101 2.5 0.3 5.0 1.5 5.00 0.25 00110 3.0 0.4 6.0 1.8
6.00 0.30 00111 3.5 0.4 7.0 2.1 7.00 0.35 01000 4.0 0.5 8.0 2.4
0.40 01001 4.5 0.5 9.0 2.7 0.45 01010 5.0 0.6 10.0 3.0 0.50 01011
5.5 0.7 11.0 3.3 0.55 01100 6.0 0.7 12.0 3.6 0.60 01101 6.5 0.8
13.0 3.9 0.65 01110 7.0 0.8 14.0 4.2 0.70 01111 7.5 0.9 15.0 4.5
0.75 10000 8.0 16.0 0.80 10001 8.5 17.0 0.85 10010 9.0 18.0 0.90
10011 9.5 19.0 0.95 10100 10.0 20.0 1.00 10101 10.5 21.0 1.05 10110
11.0 22.0 1.10 10111 11.5 23.0 1.15 11000 12.0 24.0 1.20 11001 12.5
25.0 1.25 11010 13.0 26.0 1.30 11011 13.5 27.0 1.35 11100 14.0 28.0
1.40 11101 14.5 29.0 1.45 11110 15.0 30.0 1.50 11111 15.5 31.0
1.55
[0052] The power segment 528 is an encoded segment that specifies
the desired amount of power (in watts). A table of an exemplary
encoding of the power segment 528 (the code uses the lowest 5 bits
of the byte; the other 3 bits in the byte may be reserved for
future code expansion or left unused):
TABLE-US-00003 Power b4 b0 Watts 00000 0 00001 0.5 00010 1 00011
1.5 00100 2 00101 2.5 00110 3 00111 3.5 01000 4 01001 4.5 01010 5
01011 5.5 01100 6 01101 6.5 01110 7 01111 7.5 10000 8 10001 14 High
Power 10010 20 High Power 10011 26 High Power 10100 32 High Power
10101 38 High Power 10110 44 High Power 10111 50 High Power 11000
56 High Power 11001 62 High Power 11010 68 High Power 11011 74 High
Power 11100 80 High Power 11101 86 High Power 11110 92 High Power
11111 98 High Power
[0053] It should be appreciated, however, that the packet protocol
and encodings described above are merely exemplary. The protocol
may take on an alternative format and may include more or less
information that that described above. Furthermore, the parameters
may specified by an alternative format or encoding than those
described above.
[0054] Attention is now directed to FIGS. 6 and 7, which are state
diagrams illustrating digital communication states of a power
supply and of a device, respectively, in accordance with some
embodiments. The power supply state diagram 600 and the device
state diagram 700 illustrate the states of the power supply and the
device, respectively, with respect to the exchange of digital
messages.
[0055] The power supply is initially in an idle state (602) with
respect to a device. For example, while the device is not
electrically coupled to the power supply, the power supply is in
the idle state 602 with respect to the device. It should be
appreciated that the power supply may be in the idle state 602 with
respect to a device that is electrically coupled to the power
supply. It should further be appreciated that while a power supply
is in the idle state 602 with respect to one device, it may be in
another state with another device that is electrically coupled to
the power supply. While the power supply is in the idle state 602,
the power supply is passively waiting for a message from the
device. After a message from the device is received by the power
supply, the power supply performs error detection on the message
from the device by verifying the checksum 510 (606). If there is an
error, a NACK message is sent to the device (604) and the power
supply returns to the idle state 602 to wait for the next message
from the device. If the message does not contain errors, the
contents of the message, including the vendor code 504 and the
payload 508, is inspected (608). If the message is unrecognized,
for example, because it is a proprietary message and the vendor or
manufacturer code 504 is an unrecognized vendor or manufacturer
(e.g., because the power supply and the device are made by
different manufacturers), a CAN message is sent (610) and the power
supply returns to the idle state 602. If the message is recognized,
an ACK message is sent (612) and the power supply returns to the
idle state (602) to wait for further messages from the device. It
may be the case that once the power supply recognizes the message
and sends an ACK message, the power supply may configure itself to
supply power to the device.
[0056] A device, when coupled to a power supply, may enter into a
communication mode and send a message (702). For example, when the
device is first connected to the power supply, the device may draw
power from the +5V wake-up voltage to power its microprocessor 302
and execute instructions to send a message, such as a power
statement message. After a message is sent, the device waits for a
response message from the power supply. If no response is received
after a predefined receive timeout, the message is resent (702).
If, after a predefined number of attempts, e.g., 8 attempts, to
transmit the same message, no response is received, the device goes
into a suspend state 710. In some embodiments, while in the suspend
state, a device will no longer attempt to send a proprietary
message, although non-proprietary information may still be sent. In
other embodiments, for example after a receive timeout, a device
will no longer attempt to attempt to transmit messages until a new
power supply connection is established.
[0057] If a response message is received, the device performs error
detection on the message from the power supply by verifying the
checksum 510 (706). If there is an error, the device backs off in
accordance with a backoff timer (704). After the backoff timer has
timed out, the message is resent (702).
[0058] If the message does not have errors, the contents of the
message, particularly the message type, is inspected (708). If the
message is an ACK message, the device exits the communication mode.
If the message is a NACK message, the device backs off in
accordance with backoff timer (704) and then resends the message
(702). Of course, the device may enter the communication mode
later, to send another message, if needed. If the message is a CAN
message, the device enters the suspend state 710. In embodiments
where the device can send messages containing proprietary
information, a CAN message means that the power supply does not
recognize the vendor/manufacturer of the device, as indicated by
the vendor/manufacturer identifier 504. This means that any message
containing proprietary information will not be properly processed
by the power supply since the power supply will not know the proper
format of the proprietary information payload. Therefore, the
device enters into the suspend state 710, where the device will
suspend transmission of information that invoked the CAN response,
i.e., the device will not send messages with proprietary
information to the power supply, although other communications may
take place.
[0059] The foregoing description, for purpose of explanation, has
been described with reference to specific embodiments. However, the
illustrative discussions above are not intended to be exhaustive or
to limit the invention to the precise forms disclosed. Many
modifications and variations are possible in view of the above
teachings. The embodiments were chosen and described in order to
best explain the principles of the invention and its practical
applications, to thereby enable others skilled in the art to best
utilize the invention and various embodiments with various
modifications as are suited to the particular use contemplated.
* * * * *