U.S. patent application number 10/287853 was filed with the patent office on 2003-06-05 for cellular radio telephone set.
This patent application is currently assigned to NEC Corporation. Invention is credited to Shinohara, Masahito.
Application Number | 20030104836 10/287853 |
Document ID | / |
Family ID | 19167189 |
Filed Date | 2003-06-05 |
United States Patent
Application |
20030104836 |
Kind Code |
A1 |
Shinohara, Masahito |
June 5, 2003 |
Cellular radio telephone set
Abstract
This invention relates to a cellular radio telephone set having
a USB peripheral circuit which realizes a USB connection function.
When the cellular radio telephone set is connected to an
information processing terminal apparatus via a USB cable, a
voltage Vbus supplied from the information processing terminal
apparatus is regulated and supplied to the USB peripheral circuit.
When the cellular radio telephone set is not connected to the
information processing terminal apparatus via the USB cable, an
application CPU which controls the USB peripheral circuit is
shifted to a sleep mode.
Inventors: |
Shinohara, Masahito; (Tokyo,
JP) |
Correspondence
Address: |
OSTROLENK FABER GERB & SOFFEN
1180 AVENUE OF THE AMERICAS
NEW YORK
NY
100368403
|
Assignee: |
NEC Corporation
|
Family ID: |
19167189 |
Appl. No.: |
10/287853 |
Filed: |
November 1, 2002 |
Current U.S.
Class: |
455/557 ;
455/559 |
Current CPC
Class: |
Y02D 30/70 20200801;
H04W 52/0267 20130101; H04M 1/72409 20210101 |
Class at
Publication: |
455/557 ;
455/559 |
International
Class: |
H04M 001/00; H04B
001/38 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 21, 2001 |
JP |
355498/2001 |
Claims
What is claimed is:
1. A cellular radio telephone set having a USB peripheral circuit
which realizes a USB connection function, wherein when the cellular
radio telephone set is connected to an information processing
terminal apparatus via a USB cable, a voltage Vbus supplied from
the information processing terminal apparatus is regulated and
supplied to the USB peripheral circuit.
2. A cellular radio telephone set having a USB peripheral circuit
which realizes a USB connection function, wherein when the cellular
radio telephone set is not connected to an information processing
terminal apparatus via a USB cable, an application CPU which
controls the USB peripheral circuit is shifted to a sleep mode.
3. A cellular radio telephone set having a USB peripheral circuit
which realizes a USB connection function, wherein when the cellular
radio telephone set is connected to an information processing
terminal apparatus via a USB cable, a voltage Vbus supplied from
the information processing terminal apparatus is regulated and
supplied to the USB peripheral circuit, and when the cellular radio
telephone set is not connected to the information processing
terminal apparatus via the USB cable, an application CPU which
controls the USB peripheral circuit is shifted to a sleep mode.
4. A cellular radio telephone set having a USB peripheral circuit
which realizes a USB connection function, wherein when the cellular
radio telephone set is not connected to an information processing
terminal apparatus via a USB cable, an application CPU which
controls the USB peripheral circuit is shifted to a sleep mode, and
when the cellular radio telephone set is connected to the
information processing terminal apparatus via the USB cable, the
application CPU is waked up.
5. A telephone set according to claim 2, wherein the sleep mode
includes a low-power consumption operation mode.
6. A telephone set according to claim 3, wherein the sleep mode
includes a low-power consumption operation mode.
7. A telephone set according to claim 4, wherein the sleep mode
includes a low-power consumption operation mode.
8. A telephone set according to claim 1, wherein whether the
cellular radio telephone set is connected to the information
processing terminal apparatus via the USB cable is determined by
detecting presence/absence of the voltage Vbus supplied from the
information processing terminal apparatus.
9. A telephone set according to claim 2, wherein whether the
cellular radio telephone set is connected to the information
processing terminal apparatus via the USB cable is determined by
detecting presence/absence of the voltage Vbus supplied from the
information processing terminal apparatus.
10. A telephone set according to claim 3, wherein whether the
cellular radio telephone set is connected to the information
processing terminal apparatus via the USB cable is determined by
detecting presence/absence of the voltage Vbus supplied from the
information processing terminal apparatus.
11. A telephone set according to claim 4, wherein whether the
cellular radio telephone set is connected to the information
processing terminal apparatus via the USB cable is determined by
detecting presence/absence of the voltage Vbus supplied from the
information processing terminal apparatus.
12. A telephone set according to claim 5, wherein whether the
cellular radio telephone set is connected to the information
processing terminal apparatus via the USB cable is determined by
detecting presence/absence of the voltage Vbus supplied from the
information processing terminal apparatus.
13. A cellular radio telephone set having a USB connection
function, comprising a USB connector which is connected to a USB
cable connected to an information processing terminal apparatus
including a personal computer, a USB device controller circuit for
communicating with the information processing terminal apparatus
via the USB connector connected to the USB cable, an application
CPU-which controls the whole USB, a control CPU which controls the
whole cellular radio telephone set, a regulator circuit which
converts a voltage Vbus supplied from the information processing
terminal apparatus via the USB cable into a voltage for the USB
device controller circuit, and a Vbus detection circuit which
detects presence/absence of the voltage Vbus.
14. A telephone set according to claim 13, wherein said USB device
controller circuit comprises a D+ pull-up circuit which pulls up a
signal D+ for data communication with the information processing
terminal apparatus, a controller which controls said D+ pull-up
circuit, and a transmission/reception circuit which performs
transmission/reception of USB data communication.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a cellular radio telephone
set and, more particularly, to a cellular radio telephone set
having a USB (Universal Serial Bus) peripheral circuit which
realizes a USB connection function.
[0003] 2. Description of the Prior Art
[0004] Cellular radio telephone sets are desired to have reduced
size and weight for portability, and their internal batteries are
also reduced in size and weight. However, a small-size,
light-weight internal battery means a short service life. The
cellular radio telephone must always be ON to ensure a long standby
time because the user does not know when he/she may receive an
incoming call. Therefore, the cellular radio telephone set must
reduce its power consumption to prolong the standby time.
[0005] Recent cellular radio telephone sets are connected to
information processing terminal apparatuses such as a personal
computer (to be simply referred to as a PC hereinafter) and a PDA
(Personal Digital Assistants), realizing information exchange with
the information processing terminal apparatuses and mobile
communication using the telephone network of the cellular radio
telephone set. At this time, the information processing terminal
apparatus and cellular radio telephone set are connected using,
e.g., a USB.
[0006] In the use of the USB, the cellular radio telephone set must
be newly equipped with a USB peripheral circuit such as a USB
device controller circuit. Power for operating the USB peripheral
circuit is further required.
[0007] For the USB, a suspend mode is generally prepared. Using the
suspend mode can reduce the power consumption of the USB peripheral
circuit when the cellular radio telephone set is not connected to
the information processing terminal apparatus.
[0008] Even the suspend mode cannot completely eliminate the power
consumption of the USB peripheral circuit, and a current of about
500 mA may flow at maximum. Demands have arisen for a further
improvement in this respect.
SUMMARY OF THE INVENTION
[0009] The present invention has been made in consideration of the
above situation, and has as its object to provide a cellular radio
telephone set having a USB connection function capable of
minimizing the power consumption of the internal battery of the
cellular radio telephone set both when the cellular radio telephone
set is connected to an information processing terminal apparatus
via a USB cable and when it is not connected to it.
[0010] To achieve the above object, according to the first
principal aspect of the present invention, there is provided a
cellular radio telephone set having a USB peripheral circuit which
realizes a USB connection function, wherein when the cellular radio
telephone set is connected to an information processing terminal
apparatus via a USB cable, a voltage Vbus supplied from the
information processing terminal apparatus is regulated and supplied
to the USB peripheral circuit, and when the cellular radio
telephone set is not connected to the information processing
terminal apparatus via the USB cable, an application CPU which
controls the USB peripheral circuit is shifted to a sleep mode.
[0011] In the cellular radio telephone set according to the first
principal aspect, the sleep mode includes a low-power consumption
operation mode.
[0012] In the cellular radio telephone set according to the first
principal aspect, whether the cellular radio telephone set is
connected to the information processing terminal apparatus via the
USB cable is determined by detecting presence/absence of the
voltage Vbus supplied from the information processing terminal
apparatus.
[0013] To achieve the above object, according to the second
principal aspect of the present invention, there is provided a
cellular radio telephone set having a USB connection function,
comprising a USB connector which is connected to a USB cable
connected to an information processing terminal apparatus including
a personal computer, a USB device controller circuit for
communicating with the information processing terminal apparatus
via the USB connector connected to the USB cable, an application
CPU which controls the whole USB, a control CPU which controls the
whole cellular radio telephone set, a regulator circuit which
converts a voltage Vbus supplied from the information processing
terminal apparatus via the USB cable into a voltage for the USB
device controller circuit, and a Vbus detection circuit which
detects presence/absence of the voltage Vbus.
[0014] In the cellular radio telephone set according to the second
principal aspect, the USB device controller circuit comprises a D+
pull-up circuit which pulls up a signal D+ for data communication
with the information processing terminal apparatus, a controller
which controls the D+ pull-up circuit, and a transmission/reception
circuit which performs transmission/reception of USB data
communication.
[0015] As is apparent from the above aspects, according to the
present invention, the cellular radio telephone set having the USB
connection function can minimize the power consumption of the
internal battery of the cellular radio telephone set both when the
cellular radio telephone set is connected to an information
processing terminal apparatus via a USB cable and when it is not
connected to it.
[0016] The present invention can reduce the power consumption of
the internal battery in the standby state of the cellular radio
telephone set and prolong the standby time.
[0017] The above and many other objects, features and advantages of
the present invention will become manifest to those skilled in the
art upon making reference to the following detailed description and
accompanying drawings which a preferred embodiment incorporating
the principle of the present invention are shown by way of an
illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a block diagram showing the power control
arrangement of the USB peripheral circuit of a cellular radio
telephone set according to an embodiment of the present invention;
and
[0019] FIG. 2 is a flow chart showing the operation of the cellular
radio telephone set shown in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] A preferred embodiment of the present invention will be
described in detail below with reference to the accompanying
drawings.
[0021] In the present invention, a USB peripheral circuit in a
cellular radio telephone set is operated by only power supplied
from an information processing terminal apparatus such as a PC
serving as a host, preventing the consumption of the internal
battery of the cellular radio telephone set. When the cellular
radio telephone set is not connected to the information processing
terminal apparatus such as a PC, the application CPU is also
shifted to a sleep mode, i.e., low-power consumption operation
mode, reducing the power consumption of the internal battery of the
cellular radio telephone set.
[0022] The present invention comprises a circuit which regulates a
voltage Vbus supplied from the information processing terminal
apparatus and supplies the regulated voltage to the USB peripheral
circuit, and a circuit which detects Vbus. Vbus is supplied to a
USB device controller circuit to prevent the consumption of the
internal battery of the cellular radio telephone set. The
application CPU is shifted to the low-power consumption operation
mode to reduce the power consumption of the internal battery of the
cellular radio telephone set.
[0023] FIG. 1 is a block diagram showing the power control
arrangement of the USB peripheral circuit of the cellular radio
telephone set according to the embodiment of the present
invention.
[0024] The cellular radio telephone set of the embodiment comprises
a USB connector 1 which is connected to a USB cable connected to an
information processing terminal apparatus such as a PC, a USB
device controller circuit 2 for communicating with the information
processing terminal apparatus via the USB connector 1 connected to
the USB cable, an application CPU 4 which controls the whole USB, a
control CPU 5 which controls the entire cellular radio telephone
set, a regulator circuit 6 which converts the voltage Vbus supplied
from the information processing terminal apparatus via the USB
cable into a voltage for the USB device controller circuit 2, and a
Vbus detection circuit 7 which detects the presence/absence of the
voltage Vbus.
[0025] The USB device controller circuit 2 comprises a D+ pull-up
circuit 3 which pulls up a signal D+ for data communication with
the information processing terminal apparatus, a controller 8 which
controls the D+ pull-up circuit 3, and a transmission/reception
circuit 9 which performs transmission/reception of USB data
communication.
[0026] As shown in FIG. 1, the cellular radio telephone set of the
embodiment comprises the regulator circuit 6 which converts 5V Vbus
into 3.3V and supplies 3.3V to the USB device controller circuit 2.
This can prevent the power consumption of the cellular radio
telephone set.
[0027] The cellular radio telephone set of the embodiment further
comprises the Vbus detection circuit 7. When the Vbus detection
circuit 7 detects the presence of Vbus, the control CPU 5 shifts
the application CPU 4 to the sleep mode, thereby reducing the power
consumption. When the Vbus detection circuit 7 detects the presence
of Vbus, the control CPU 5 wakes up the application CPU 4. The USB
device controller circuit 2 is so controlled as to pull up D+. A
sequence of communicating with the information processing terminal
apparatus such as a PC is realized.
[0028] The cellular radio telephone set of this embodiment will be
explained in more detail with reference to FIG. 1.
[0029] The regulator circuit 6 converts 5V Vbus supplied via the
USB connector 1 into 3.3V, and supplies this regulated voltage
(3.3V) to the USB device controller circuit 2.
[0030] The USB device controller circuit 2 incorporates the pull-up
circuit 3 which pulls up D+ under the control of the controller 8.
The cellular radio telephone set comprises the Vbus detection
circuit 7. A Vbus detection signal from the Vbus detection circuit
7 is sent to the control CPU 5. The control CPU 5 shifts the
application CPU 4 to the sleep mode or wakes it up on the basis of
the Vbus detection signal.
[0031] When the cellular radio telephone set is not connected to
the information processing terminal apparatus such as a PC, no
Vbus, D+, or D- is supplied to the cellular radio telephone set. In
this state, no power is supplied to the USB device controller
circuit 2. At this time, the Vbus detection circuit 7 detects that
no Vbus is supplied. The control CPU 5 shifts the application CPU 4
to the low-power consumption operation mode (e-g-, decreases the
operation clock or turns off the power supply of a specific block).
Accordingly, the power consumption of the internal battery in the
standby state of the cellular radio telephone set can be
reduced.
[0032] When the cellular radio telephone set is connected to the
information processing terminal apparatus, Vbus is converted into
3.3 V by the regulator circuit 6 and then supplied to the USB
device controller circuit 2. The Vbus detection circuit 7 detects
Vbus, and a Vbus detection signal is recognized by the control CPU
5.
[0033] The subsequent operation will be explained with reference to
the flow chart of FIG. 2.
[0034] If the information processing terminal apparatus and
cellular radio telephone set are connected by a USB cable (A-1),
the Vbus detection circuit 7 detects Vbus (connection to the host).
At the same time, power is supplied to the USB device controller
circuit 2 (A-2).
[0035] The control CPU 5 wakes up the application CPU 4 on the
basis of a Vbus detection signal from the Vbus detection circuit 7
((A-3) and (A-4)). After the end of activation, the application CPU
4 initializes the USB device controller circuit 2 (A-5).
[0036] The controller 8 and D+ pull-up circuit 3 of the USB device
controller circuit 2 pull up D+(A-6). In response to D+ pull-up
operation, USB communication starts (A-7).
[0037] Note that execution of D+ pull-up operation before
activation of the application CPU causes a problem in USB
connection and should be avoided.
* * * * *