JPH0559519U - Portable electronic devices - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a portable electronic device that can prolong battery life when a peripheral device that requires a normal power supply voltage (5 V) is not connected to a battery-driven device. .. A battery-driven device 10 and a peripheral device 20 sharing a power supply can be connected, and a signal line 153 for controlling a power supply voltage is provided in an interface 15, and a power supply circuit 21 for changing the power supply voltage by the signal line 153. The peripheral device 2 that requires a normal power supply voltage (5 V)
Depending on whether 0 is connected or not, the power supply voltage of the battery-driven device 10 can be set to an optimum value. Therefore, when the peripheral device 20 is not connected, the battery-driven device 10
Since the power supply voltage can be lowered, the power consumption can be reduced, which extends the battery life.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a portable electronic device having an integrated IC, and more particularly to a portable electronic device with reduced power consumption.

[0002]

[Prior art]

 As shown in FIG. 2, a conventional battery-driven device considering expandability generally includes a battery 31, which is a main power source, and an electronic circuit 33 and a peripheral device interface 35 which output a constant voltage using the battery 31 as a power source. It is composed of a power supply circuit 32 that supplies electric power to the device, an electronic circuit 33 that actually performs system processing of the device, and an interface 35 with peripheral devices. The peripheral device interface 35 has a power supply line 351 for supplying electric power to the peripheral device, and a bus 352 for exchanging data between the electronic circuit 43 of the peripheral device 40 and the electronic circuit 33 of the battery-driven device 30. Further, the peripheral device 40 connectable to the battery-driven device 30 is composed of an electronic circuit 43 that performs processing of the peripheral device 40. Then, by connecting the battery-driven device 30 and the peripheral device 40 through the peripheral device interface 35, the electronic circuit 43 is supplied with power from the power supply line 351 of the peripheral device interface 35, and the battery 352 is driven by the bus 352. It exchanges data with the electronic circuit 33.

In particular, the power supply circuit 32 is necessary in order to make the output voltage of the battery 31 which changes greatly depending on the environment constant and supply it to the electronic circuit. Therefore, in order to keep the battery voltage constant, the power supply circuit 32 steps up or down to supply power to the electronic circuit 33 of the battery-driven device 30.

In order to reduce the power consumption of the electronic circuit 33, a CMOS IC having low power consumption is often used. As a characteristic of the CMOS IC, the power consumption has a relationship proportional to the power supply voltage. Therefore, the power supply voltage is set to a lower voltage (about 3 V) than the power supply voltage (5 V) normally used for TTL or the like. However, the ICs are those that are specially guaranteed for low-voltage operation by selecting from those designed specifically for low-voltage operation and those designed for normal power supply voltage (5V).

Since portability of the battery-driven device 30 is important, reduction in size and weight is required. Similarly, since the peripheral device 40 is required to be small and lightweight, the peripheral device 40 itself does not have a power supply and a power supply circuit and often uses the power supplied from the power supply circuit 32 as its own power supply.

[0006]

[Problems to be solved by the device]

 When using an IC that can operate only with a normal power supply voltage (5V) in a conventional portable electronic device, the power supply voltage of a battery-driven device must be raised to the normal power supply voltage.

Particularly, when the peripheral device to which the battery-powered device supplies power uses an IC that can operate only at the normal power supply voltage, the power supply voltage of the battery-powered device is also the normal power supply voltage (5 V). Must be set to. However, even when this peripheral device is not used, the power supply voltage of the battery-powered device must be set to be high, which causes a problem that the power consumption of the battery-powered device is increased and the battery life is shortened. It was

For example, when it is desired to use an IC such as an electronic notebook that can be added with a special function by an IC card and can operate only at a normal power supply voltage (5 V) in the IC card, a power source for the electronic notebook is used. The voltage must be set high. However, in such a case, even when the IC card is not used, the power supply voltage on the electronic notebook side remains high, power consumption increases, and battery life shortens.

Therefore, an object of the present invention is to provide a portable electronic device capable of prolonging battery life when a peripheral device that requires a normal power supply voltage (5 V) is not connected to a battery-driven device. To do.

[0010]

[Means for Solving the Problems]

 Therefore, in order to achieve the above-mentioned object, the portable electronic device of the present invention uses the battery as a power source and the peripheral device interface for exchanging various signals with the battery and the first electronic circuit for system processing. A battery-driven device having a power supply circuit that outputs a voltage and supplies electric power to the electronic circuit and the peripheral device interface, a second electronic circuit that performs system processing, and a control circuit that controls the power supply circuit. It is characterized in that it is configured with a peripheral device having.

The peripheral device interface includes a power supply line for supplying power to the peripheral device, a bus for exchanging data between the second electronic circuit and the first electronic circuit, and a control signal for the output voltage of the power supply circuit. It is characterized by being configured with a signal line for transmitting the.

[0012]

[Action]

 This is a book that can be connected to battery-driven electronic devices and peripheral devices that share a power source, has a control line for controlling the power source voltage in the interface, and has a power supply circuit that changes the power source voltage by the control line. In the present invention, for example, a power supply circuit that realizes a low power supply voltage (about 3 V) when the power supply voltage control line is open and a normal power supply voltage (5 V) when grounded is realized in a battery-powered device, By grounding the control line that controls the power supply voltage of the peripheral device that requires the normal power supply voltage, do not connect the power supply of the battery-driven device to the normal power supply voltage (5V) when the peripheral device is connected. If it does, the power supply voltage is set to a low power supply voltage.

Therefore, it becomes possible to set the power supply voltage of the battery-driven device to an optimum value depending on the presence / absence of the connection of the peripheral device which requires the normal power supply voltage (5 V), and when the peripheral device is not connected, the battery Power consumption can be reduced because the power supply voltage of the drive type device can be lowered. Then, reducing the power consumption extends the battery life.

[0014]

【Example】

 Next, an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing an embodiment of a portable electronic device according to the present invention. In FIG. 1, a battery-driven device 10 includes a battery 11, a power supply circuit 12 that uses the battery 11 as a power source, outputs a constant voltage, and supplies power to the first electronic circuit 13 and the peripheral device interface 15, and It is composed of a first electronic circuit 13 for performing system processing of the device and a peripheral device interface 15. The peripheral device interface 15 exchanges data between the power supply line 151 that supplies power to the peripheral device 20, the second electronic circuit 23 of the peripheral device 20, and the first electronic circuit 13 of the battery-powered device 10. It has a bus 152 and a signal line 153 for transmitting a control signal of the output voltage of the power supply circuit 12. Then, the power supply circuit 12 outputs a power supply voltage according to the state of the control line 153 of the output voltage of the peripheral device interface 15.

Further, the peripheral device 20 includes a second electronic circuit 23 that performs processing of the peripheral device 20 and a control circuit 24 that controls the power supply circuit 12. Then, by connecting the battery-driven device 10 and the peripheral device 20 through the peripheral device interface, the second electronic circuit 23 and the control circuit 24 are supplied with power from the power supply line 151 of the peripheral device interface 15, and the second electronic circuit 23 and the control circuit 24 are supplied. The circuit 23 exchanges data with the first electronic circuit 13 of the battery-powered device 10 via the bus 152, and the signal line 153 transmits a signal from the control circuit 24 to the power supply circuit 12 of the battery-powered device 10.

In the battery-driven device 10 configured as described above, the power supply voltage of the power supply circuit 12 of the battery-driven device 10 can be changed depending on whether the peripheral device 20 is connected or not. Then, when the peripheral device 20 that requires the normal power supply voltage is connected, the output voltage of the power supply circuit 12 is set to the high voltage required by the peripheral device 20, and when the peripheral device 20 is not connected, The output voltage of the power supply circuit 12 is set to a power supply voltage low enough to operate the first electronic circuit 13 in the battery-powered device 10.

That is, when the peripheral device 20 is not connected, the power supply voltage of the battery-driven device 10 can be lowered, so that power consumption can be reduced. And by reducing power consumption, battery life is extended.

[0018]

[Effect of the device]

 As described above, according to the present invention, a battery-driven electronic device and a peripheral device sharing a power supply can be connected, and a control line for controlling the power supply voltage is provided in the interface, and the power supply voltage is changed by the control line. It is possible to set the power supply voltage of the battery-powered device to the optimum value by connecting the peripheral device that requires the normal power supply voltage (5V) and not connecting the peripheral device. At times, the power supply voltage of a battery-powered device can be reduced, resulting in a reduction in power consumption, and a reduction in power consumption results in a longer battery life.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a portable electronic device of the present invention.

FIG. 2 is a block diagram showing a conventional portable electronic device.

[Explanation of symbols]

 10 Battery Driven Device 11 Battery 12 Power Supply Circuit 13 First Electronic Circuit 15 Peripheral Device Interface 151 Power Supply Line 152 Bus 153 Signal Line 20 Peripheral Device 23 Second Electronic Circuit 24 Control Circuit

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location 7165-5B G06F 1/00 330 F 7165-5B 334 Z

Claims (2)

[Scope of utility model registration request] 1. A battery, a peripheral device interface for exchanging various signals with a first electronic circuit for performing system processing, and a constant voltage output from the battery as a power source for supplying electric power to the electronic circuit and the peripheral device interface. A battery-powered device having a power supply circuit for supplying power; a second electronic circuit for performing system processing; and a peripheral device having a control circuit for controlling the power supply circuit. And portable electronic equipment. 2. The peripheral device interface includes a power supply line for supplying power to the peripheral device, a second electronic circuit, and a first electronic circuit.
2. The portable electronic device according to claim 1, comprising a bus for exchanging data of the electronic circuit and a signal line for transmitting a control signal of an output voltage of the power supply circuit.