JPS63211415A - Power source circuit for electronic equipment - Google Patents

Abstract

PURPOSE:To reduce the consumption of a battery by coupling a cartridge to an electronic equipment body from the outside, and setting a prescribed time in a power source control means of an auto power OFF APO function, based on a data which has been stored in its cartridge. CONSTITUTION:ON and OFF of an APO are determined by each loop for deciding the time of using an AC adapter 6 or the time of using a battery 2, and for deciding a card 13 or an equipment body 1, and setting of the APO is executed in a prescribed time, respectively. That is, when the APO is ON, the APO is executed by counting down a counter for counting time, in a timer 17, and based on a data in the equipment body or a cartridge, a desired timer time can be set. In such a way, the consumption of a battery can be prevented.

Description

[Detailed Description of the Invention] <<> Industrial Application Field The present invention relates to power supply circuits for electronic devices, and particularly relates to power supply circuits that have a function called auto power-off, which cuts off the power supply line if the condition continues. .

■) Conventional technology In general, small electronic devices use dry batteries or NiCd batteries as rechargeable secondary batteries as a driving power source.Indoors, they are used to suppress the consumption of the dry batteries and to charge the NiCd batteries. , with the AC adapter,
A DC voltage rectified from an AC power source is used in place of the dry battery, and in the case of NiCd batteries, a so-called floating circuit configuration is often used to charge the NiCd battery and supply power to the load.

Furthermore, when driving a load using the above-mentioned dry batteries or secondary batteries, for example when the use of a calculator, electronic dictionary, etc. is interrupted for a considerable period of time, the display element and its drive stage circuitry may be damaged. A power control circuit called auto power off (hereinafter referred to as APO) that cuts off the power has begun to be adopted.

In this case, a timer circuit is installed in the electronic device to cut off the power to the load (turn off).
No. 4-37937 discloses a power supply switching means that detects a non-use state of a computer for a predetermined time period and switches off the operation of a control means that cuts off the power supply to a display device when the non-use state for a predetermined time period has elapsed. shows a configuration in which it is forcibly inactivated when an external power source is used.

Q9 Problems to be Solved by the Invention In the conventional power supply circuit of an electronic device, the so-called auto power off (APO) is activated by the control circuit using a built-in battery to detect when the computer is not in use for a predetermined period of time. However, there is also a demand that the predetermined time width is too short for computers and electronic dictionaries, even when the display is powered by batteries.This is because the APO is turned on. If the above-mentioned predetermined time period is exceeded and you wish to further examine or read the displayed contents, the control circuit will be activated and the power will be cut off due to the detection of the above-mentioned non-use state, causing the data to be lost. There was a drawback that you had to key in again.

Therefore, the present invention proposes a new power supply circuit for electronic equipment that eliminates the above-mentioned drawbacks.

B.) Means for Solving the Problems The present invention provides a plurality of load circuits driven by the voltage of a DC power line connected to the output side of a battery or an AC adapter, and a plurality of load circuits connected in series to the DC power line. In a power supply circuit of an electronic device including a power switch and a power control means for cutting off power supply to a part of the load when the power switch is closed, a cartridge is externally coupled to the main body of the electronic device, The predetermined time in the power supply control means is set based on data stored in the cartridge.

K) Function In the power supply circuit for an electronic device of the present invention, a power supply control means is provided in the main body of the electronic device, and various APO time settings can be selected in the power supply control means by coupling an external cartridge such as a ROM card. When the cartridges are individually connected to the main body, the optimum time can be set.

(Example: To explain the present invention according to the drawings, FIG. 1 shows a configuration diagram of a power supply circuit of an electronic device according to the present invention, and FIG. 2 shows a flowchart for explaining the power supply circuit.

In the drawings, (1) is the electronic device body, (2) is the battery,
(3) is the battery switch, (4) is the power switch, (5
) is a power supply terminal for connecting the AC adapter (6), (7) is a power line, and (8x9) is a flip-flop and a power detection stabilizing circuit as power control means directly connected to the power line. It has become a load. (10) is an input unit such as a keyboard for inputting data; (11) is a CPU as a central information processing means; (11) is a CPU as a central information processing means;
2) is a latch circuit, and Q3) is a card as a cartridge storing data such as a ROM that is externally connected to the main body of the electronic device.

(14) is based on the output from the power supply detection stabilization circuit,
a power supply oscillation and output circuit that supplies power to the CPU and latch circuit; (15) a power control switch that controls the operation of the power supply oscillation and output circuit by the flip-flop; and (16) a power supply detection signal line; show.

Next, the operation of the power supply circuit according to the present invention will be explained with respect to the case where an AC adapter is used and the case where an internal battery is used.

First, we will explain the case where the AC adapter (6) is connected to the power supply terminal (5).
) is a primary battery such as a dry cell, the battery switch (
3) is turned off, while in the case of a <21st order battery such as a NiCd battery, the battery switch (3) is kept on.

At this time, the power switch (4) is turned on and the output of the AC adapter (6) is applied to the flip-flop (8) and the power detection stabilizing circuit (9) through the power line (7). Here, the power supply detection stabilizing circuit (9) is connected to the AC adapter (6).
CPU (
11) by a signal on the power supply detection line (16),
The timer (17) provided in the CPU (11) is kept inactive. That is, the Q output of the flip-flop (8) is low (L), and the power control switch (15) remains on.

Therefore, the power control switch (15) is turned on while the power switch (4) is on, and the power supply oscillation and output circuit (14) is connected to the CPU (11) and the display element (1).
Power is constantly supplied to loads such as 8).

Next, when the AC adapter (6) and the electronic device body (1) are uncoupled, the battery switch (3) is turned on, and when the power switch (4) is turned on, the power line (7) is turned on.
) is applied to the flip-flop (8) and the power supply detection stabilizing circuit (9), and since the power supply line (7) does not contain any ripple, the power supply detection stabilizing circuit (9)
The detection output of is applied to the CPU (11) by the signal of the power supply detection line (16), and the timer (17) is activated.

At this time, the output from the power supply oscillation and output circuit (14) is applied to the CPU (11) and latch circuit (12) in the same manner as described above.

Therefore, the timer (17) starts a counter and counts down at the timing when the input operation from the input unit (10) starts to be stopped or interrupted. Timer one hour is T.

(minutes), the off signal is output from the CPU (11) after T0 minutes, the flip-flop (8) is set via the latch circuit (12), and the control output high (H) for APO operation is output from the Q output. ) will appear, and the power control switch (1) will appear.
5) is turned off, the operation of the power supply oscillation and output circuit (14) is stopped, and the display element (18), which consumes particularly large amount of power, is turned off.
is turned off to prevent battery consumption.

Next, when using the battery (2), turn on the power switch (4) in the same manner as described above, and then update the electronic device (1) with a function upgrade such as memory expansion or an electronic dictionary. When a card (13) having a memory in which various dictionaries are electronically converted into ROM is inserted and connected from the outside,
The card (13) has a configuration in which the APO timer is set in advance to a time different from To in the main body, with the APO timer being T. For example, if it is 5 minutes,
The CPU (11) reads T from the CPU (11) based on data corresponding to the content of the card (13), such as 3 minutes or 10 minutes, and sets the time T to the timer (17).
The specified time (T) when the input operation is stopped or interrupted.
After the APO is activated, a set output is applied to the flip-flop (8) via the latch circuit (12), the power supply control switch (15) is turned off, and the power supply oscillation and output circuit (1
4) becomes inoperable, power to one display element (18) is cut off, and battery consumption is minimized.

In addition, after turning on (activating) the APO, press the power switch (
4) is configured so that when it is turned off and turned on again, the timer (17) is reset as an initial state.
The timer (17) is restarted.

Summarizing these into a flowchart, the auto power off (APO) function is shown in Figure 2.
When using C adapter (6)) is DC (when using battery (2))
Judgment and card (13) or main body (electronic device main body) (
1) Each loop of determination determines whether the APO is on or off, and when only the electronic device main body (1) is operated, the timer time is T. , in the case of card (13), use T to set the APO using the card side program. In some cases, DC (
Even when using batteries (2), there is a desire to eliminate the need for the APOIfi function, especially when using an encyclopedia card in an electronic dictionary.
It is also possible to leave the PO off.

Therefore, when APO is on, when the APO flag is turned on, the time counter in the timer (17) is decremented (counted down), and APO is executed and some of the loads, such as the display element (18), are etc. power is cut off.

(G) Effects of the Invention According to the power supply circuit for an electronic device of the present invention, the electronic device body is provided with an automatic power off (APO) function.

When a cartridge storing various data such as a ROM for optional functions is connected to the main body of the electronic device from the outside, a desired timer of one hour can be set based on the data (program) in the cartridge. The effects of using the present invention on the electronic equipment are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a power supply circuit for an electronic device according to the present invention, and FIG. 2 is a flowchart of the same circuit. (1)...Electronic device body, (2)...Battery, (3
)...Battery switch, (4)...Power switch, (5)...Power terminal, (6)...AC adapter, (7)...Power line, (8)... Flip-flop, (9)...Power supply detection stabilization circuit, (
11)...CPU, (13)...Card,
(i4)...Power supply oscillation and output circuit, (1
5)...Power control switch, (17)...Timer.

Claims (1)

[Claims] 1. A plurality of load circuits driven by the voltage of a DC power line connected to the output side of the battery or AC adapter;
A power supply circuit for an electronic device, comprising a power switch connected in series to the DC power line, and a power control means for cutting off power supply to a part of the load when a predetermined time has elapsed with the power switch closed. A power supply circuit for an electronic device, wherein a cartridge is externally connected to a main body of the electronic device, and the predetermined time in the power supply control means is set based on data stored in the cartridge.