JPH10174286A - Battery power supply controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong service life of a battery power supply. SOLUTION: The battery power supply controller comprises a CPU 10, and a switching circuit 11 being controlled by the CPU 10 in addition to a battery power supply 7, a DC-DC converter 8 and an LSI 9 constituting a basic structure. Power consumption state of a body (entire portable terminal) is notified from an LSI 9 to the CPU 10 via a control signal line L1. When power consumption state of the body is lower than a predetermined level, the CPU 10 switches the switching circuit 11 to the battery power supply 7 side. Consequently, boosted voltage supply from the DC-DC converter 8 to the LSI 9 is switched to direct battery voltage supply from the battery power supply 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery power control device suitable for use in a portable terminal.

[0002]

2. Description of the Related Art Conventionally, as this type of battery power control device, Japanese Patent Application Laid-Open Nos.
There is a power supply control circuit as shown in JP-A-36655. FIG. 3 shows a main configuration of the power supply control circuit. In the figure, 1 is a battery power supply, 2 is a transistor Tr0 or T
a circuit composed of r1, 3 a DC-DC converter (boost converter), 4 a CPU, 5 a power switch,
Reference numeral 6 denotes a circuit including the capacitor C2. In this power supply control circuit, the power supply switch 5 is not turned on, and D
When the C-DC converter 3 is not operating, the circuit 2
And the battery power supply 1 through the DC-DC converter 3
The battery voltage (low voltage) from is supplied directly to the CPU 4,
Memory of CPU 4 (built-in memory, external memory)
Is backed up.

When the power switch 5 is turned on, the KON input of the CPU 4 goes high for a certain period of time due to the action of the capacitor C2 in the circuit 6, the voltage VDC of the CPU 4 goes low, and the transistors Tr0, Tr1 in the circuit 2
Turns on. As a result, the DC-DC converter 3 starts increasing the voltage of the battery power supply 1, and this increased voltage is applied to the CPU.
4 begins to be supplied. It takes 5 to 10 msec for the DC-DC converter 3 to generate a normal boosted voltage.
During that time, that is, until the boost voltage rises, CP
A reset pulse is supplied from a reset pulse generation circuit (not shown) to the CPU 4 so that the operation of the U4 does not cause a malfunction or abnormality, and the operation of the CPU 4 is kept stopped.

[0004]

However, according to such a conventional power supply control circuit, the battery voltage from the battery power supply 1 is directly supplied to the CPU 4 only when the power switch 5 is not turned on. Therefore, there is a problem that the life of the battery power supply 1 is shortened. That is,
When the power switch 5 is turned on, the DC-
The boosted voltage from the DC converter 3 is supplied to the CPU 4. When the power switch 5 is turned on, the power consumption of the main unit (the entire portable terminal) controlled by the CPU 4 may be small. In such a case, the efficiency of the DC-DC converter 3 is reduced, and the energy is reduced. Uselessly and shorten the life of the battery power supply 1.

[0005] The present invention has been made to solve such a problem, and an object of the present invention is to provide a battery power control device capable of extending the life of a battery power.

[0006]

In order to achieve the above object, the present invention provides a battery power supply, a booster for boosting a voltage from the battery power, and a supply of a boosted voltage from the booster. A battery power control device that directly supplies a battery voltage from a battery power supply to the control unit when the boosting unit is not operating to back up a memory of the control unit. In response to the notification of the power state, when the power consumption of the device becomes equal to or less than a predetermined value, the power supply switching means for switching the power supply voltage to the control means from the boosted voltage from the boosting means to the direct supply of the battery voltage from the battery power supply is provided. It is provided. Therefore, according to the present invention, when the power consumption of the apparatus becomes equal to or less than the predetermined value, the power supply voltage to the control means is switched from the boosted voltage from the boosting means to the direct supply of the battery voltage from the battery power supply. For example, when the power consumption of the entire portable terminal becomes equal to or less than a predetermined value, the power supply voltage to the CPU having the memory becomes DC
The switching from the boosted voltage from the DC converter to the direct supply of the battery voltage from the battery power supply is performed.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments. [Embodiment 1] FIG. 1 is a block diagram showing a main part of a battery power control device according to an embodiment of the present invention. In FIG. 1, reference numeral 7 denotes a battery power supply, 8 denotes a DC-DC converter (step-up converter), and 9 denotes an LSI having a CPU for controlling the apparatus (entire portable terminal). In this embodiment, in addition to these basic configurations, C
A PU 10 and a power supply switching circuit 11 whose switching state is controlled by the CPU 10 are provided.

[0008] The LSI 9 notifies the CPU 10 of the power consumption state of the device via the control signal line L1. Note that the LSI 9 has a functional circuit and a memory (built-in memory, external memory) necessary for this device. Further, the CPU 10 operates by receiving a battery voltage from the battery power supply 7, and uses a wide power supply voltage width that can operate normally even if the battery voltage of the battery power supply 7 fluctuates somewhat. The DC-DC converter 8 is designed to have the highest efficiency during normal operation (operation mode) of the apparatus.

Next, the operation of the battery power control device thus configured will be described separately for a normal operation and a low power consumption operation. [During Normal Operation] The LSI 9 is connected to the control signal line L1
The CPU 10 is notified of the current power consumption state of the main unit. C
When the power consumption of this unit is equal to or more than the predetermined value, the PU 2 sets the power supply switching circuit 11 to the DC-DC converter 8 side. As a result, the boosted voltage from the DC-DC converter 8 is supplied to the LSI 9 via the power supply switching circuit 11.

[Low Power Consumption Operation] The LSI 9 notifies the CPU 10 of the current power consumption state of the main unit through the control signal line L1. The CPU 10 switches the power supply switching circuit 11 to the battery power supply 7 when the power consumption of the main unit becomes equal to or less than a predetermined value. As a result, the power supply voltage to the LSI 9 becomes DC
-Switch from the boosted voltage from the DC converter 8 to the direct supply of the battery voltage from the battery power supply 7. Note that the power supply switching circuit 11 avoids momentary interruption in a transitional transition state so that power is always supplied to the main unit.

In this embodiment, the LSI 9 has a function circuit required for this device, unused functions are stopped, and only the necessary function circuit can be operated according to the situation. When the number of functional circuits operable by the LSI 9 is small, that is, when the power consumption of the unit is small (in the display mode or the data backup mode), the CPU 10 does not use the DC-DC converter 8 and uses the battery power supply. 7
Switch to direct supply of battery voltage from.

As a result, the DC-DC converter 8 can always be used with high efficiency, that is, the use of the DC-DC converter 8 with low power consumption, which is inefficient, can be avoided, and the life of the battery power source 7 can be extended. . If the LSI 9 notifies the CPU 10 that the power consumption of the main unit has become equal to or less than the predetermined value, the CPU 10 does not need to constantly monitor the power consumption of the main unit.

[Second Embodiment] FIG. 2 is a block diagram showing a main part of a battery power control device according to another embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same or equivalent components, and a description thereof will be omitted. In this embodiment, instead of the LSI 9 shown in the first embodiment,
The main CPU 12 and the LSI 13 are used. LSI1
Reference numeral 3 has a built-in peripheral function for controlling the power mode of the main CPU 12 and the main unit (portable terminal).

When controlling the power mode of the main unit, the LSI 13 notifies the CPU 10 via the control signal line L1 when it determines that the power consumption of the main unit falls below a predetermined value. The CPU 10 includes an LSI via the control signal line L1.
13, the power supply to the LSI 13 is switched to D.
In order to switch from the boosted voltage from the C-DC converter 8 to the direct supply of the battery voltage from the battery power supply 7, the switching state in the power supply switching circuit 11 is switched.

The current value in the portable terminal differs depending on the power mode. There is a difference in the current value between the operation mode, the display mode, and the data backup mode. For this reason, D
In the C-DC converter 8, it is difficult to achieve high efficiency for all modes. Therefore, in the present embodiment, the circuit is designed so that the DC-DC converter 8 has the highest efficiency in the operation mode. And the display mode,
In the data backup mode, the supply is switched to the direct supply from the battery power supply 7 without using the DC-DC converter 8.

[0016]

As is apparent from the above description, according to the present invention, when the power consumption of the apparatus becomes equal to or less than a predetermined value, the power supply voltage to the control means having a memory is increased by the boosted voltage from the boosting means. Can be switched to the direct supply of the battery voltage from the battery power source, the boosting means can be always used with high efficiency, and the life of the battery power source can be extended.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a main part of a battery power control device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a main part of a battery power control device according to another embodiment of the present invention.

FIG. 3 is a block diagram showing a main part of a conventional battery power control circuit.

[Explanation of symbols]

7: Battery power, 8: DC-DC converter (step-up converter), 9: LSI, 10: CPU, 11: Power supply switching circuit, L1: Control signal line, 12: Main CPU, 13: L
SI.

Claims (2)

[Claims] A booster for boosting a voltage from the battery power supply; and a controller receiving a boosted voltage from the booster. When the booster is not operated, the battery power is supplied from the battery power supply. A battery power supply control device for directly supplying the battery voltage to the control unit and backing up a memory of the control unit, receiving a notification of the power consumption state of the apparatus from the control unit,
Power supply switching means for switching a power supply voltage to the control means from a boosted voltage from the boosting means to a direct supply of a battery voltage from the battery power supply when the power consumption of the apparatus becomes a predetermined value or less. Characteristic battery power control device. 2. A power supply comprising: a battery power supply; a DC-DC converter for boosting a voltage from the battery power supply; and an integrated circuit receiving a boosted voltage from the DC-DC converter. In operation, in a battery power supply control device that directly supplies a battery voltage from the battery power supply to the integrated circuit and backs up a memory included in the integrated circuit, receives a notification of a power consumption state of the device from the integrated circuit,
A power supply switching means for switching a power supply voltage to the integrated circuit from a boosted voltage from the DC-DC converter to a direct supply of a battery voltage from the battery power supply when the power consumption of the device becomes a predetermined value or less. A battery power control device characterized by the above-mentioned.