JPH06119088A - Power supply control circuit and micro-seismoscope - Google Patents

Abstract

PURPOSE:To obtain a power supply control circuit capable of controlling power supply to a circuit requiring low power consumption and to drastically save the waste of a battery power source in a battery power source driving type micro-seismoscope. CONSTITUTION:As a seismoscope switch SW is OFF as long as an earthquake is not generated, both transistors Tr1 and Tr2 are nonconductive, the power consumption of a circuit MPU is saved and the battery power source is not wasted. On the other hand, the seismoscope switch SW is turned ON to make the transistors Tr12 and Tr2 conductive to supply the circuit MPU with power supply and even if the seismoscope switch SW repeats ON/OFF because of the earthquake, power supply to the circuit MPU is self-held.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply control circuit and a micro-type vibration sensor whose power supply is controlled by the circuit.

[0002]

2. Description of the Related Art FIG. 3 is a schematic view of a main part of a conventional micro-type vibration sensor.

In the configuration, E is a battery power source with a built-in seismic sensor, SW is a seismic switch, Tr is a switching transistor, and MPU is a one-chip microcomputer. The contact of the seismic switch SW is turned on and off by the vibration of the earthquake.

One-chip microcomputer MPU
Has a power input unit I1, signal output units O1 and O2, and a signal input unit I2.

The power source input section I1 is for the battery power source E, the signal output section O1 is for the base of the switching transistor Tr, the signal input section I2 is for the collector of the switching transistor Tr via the seismic switch SW, and the signal output section O2 is for illustration. Each is connected to an appropriate device not shown.

In operation, the microcomputer MP
The battery power source E is always directly supplied to the power source input section I1 of the U, and the microcomputer MPU is in an operable state.

When observing an earthquake, the microcomputer MPU outputs a switching signal from the signal output unit O1 to make the switching transistor Tr conductive and put it in an observation standby state. When an earthquake occurs, the seismic switch SW is turned on / off in response to the earthquake, so that the battery power E accompanying the on / off of the seismic switch SW is intermittently supplied to the signal input section I2 of the microcomputer MPU as a seismic signal. As a result, the microcomputer MPU outputs a required output from the signal output unit O2 to a device such as a gas circuit breaker or an oil stove in response to the seismic signal.

[0008]

In such a micro-type seismic sensor, the power is always supplied even when the switching signal is not given from the microcomputer MPU to the switching transistor Tr. The consumption of the built-in battery power source E over a long period of time is remarkable. Further, when the switching transistor Tr is turned on to bring it into the earthquake observation standby state, the consumption of the battery power source by the switching transistor Tr is also added, and the consumption becomes more remarkable. Thus, until now, there has been nothing to suppress the consumption of the battery power source for the micro-type seismic sensitive device, and a device that suppresses the consumption has been demanded from the practical viewpoint of the micro-type seismic sensitive device. .

The present invention has been made in view of such a demand, and a power supply control circuit and a power supply control circuit capable of remarkably suppressing power consumption in a micro-type vibration sensor or the like driven by a battery power supply. Thus, it is an object of the present invention to provide a micro-type vibration sensor whose power supply is controlled.

[0010]

In order to achieve such an object, a power supply control circuit according to a first aspect of the present invention has a control transistor and a drive transistor, and the control transistor is a control transistor. Has a collector-emitter connected between the power supply input of the circuit and a power supply, and the base connected to the collector or emitter of the drive transistor, and the drive transistor is
It is characterized in that the base is connected to the power supply input section of the circuit and the power supply via the switch, respectively.

According to a second aspect of the present invention, there is provided a micro-type vibration sensor having a circuit driven by a battery power source and the power supply control circuit according to the first aspect.
It is characterized in that it has a seismic switch as the switch.

According to a third aspect of the present invention, there is provided a micro-type vibration sensor having a circuit driven by a battery power source and the power supply control circuit according to the first aspect.
A trigger switch is provided as the switch, and a seismic switch is connected between the battery power source and the signal input section of the circuit.

[0013]

In the power supply control circuit according to the first aspect of the present invention, when the switch is turned on, the drive transistor becomes conductive when power is applied, and as a result, the control transistor also becomes conductive. Is connected to the power supply and the circuit is in operation.

Further, since the power supply input section of the circuit is connected to the base of the drive transistor, the power supplied to the power supply input section is fed back to the base of the drive transistor, and as a result, the drive transistor is switched off. However, the conductive state, that is, the control transistor is also kept conductive.

As a result, when the control transistor is in the non-conducting state, the power is not supplied to the power input section of the circuit, so that the power is not consumed. Then, power is supplied to the power input section only after the switch is turned on, and once the switch is turned on and power is supplied to the power input section, even if the switch is turned off, the power is not supplied. Power is continuously supplied to the input section.

In the micro seismoscope according to claim 2 of the present invention, since the switch is a seismic switch, a single seismic switch has a function as a power-on switch simultaneously with the detection of an earthquake. .

In the micro-type seismoscope according to claim 3 of the present invention, the power is turned on by the trigger switch,
An earthquake is detected by a seismic switch separately from the trigger switch.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings, which are applied to a micro-type vibration sensor.

FIG. 1 is a circuit diagram including a power supply control circuit according to a first embodiment of the present invention and a micro-type seismoscope whose supply of power is controlled by the power supply control circuit. In FIG. 1, E
Is a battery power source with a built-in micro seismic sensor, MPU is a one-chip microcomputer, SW is a seismic switch, Tr1 is a control transistor, Tr2 is a drive transistor, and Tr3 is a release transistor.

The control transistor Tr1 has a collector and an emitter which are the power supply input section I1 of the microcomputer MPU.
Is connected to the battery power source E, and the base is connected to the collector of the drive transistor Tr2 via the resistor R6. The drive transistor Tr2 has a base for the battery power source E, a backflow prevention diode D2,
Via the resistors R3 and R5 and the seismic switch SW, and via the resistor R2 and the backflow prevention diode D1 for the power input section I1 of the microcomputer MPU,
Each is connected.

In this example, the drive transistor Tr2
Is a npn type, its collector is connected to the base of the control transistor Tr1. However, when the drive transistor Tr2 is a pnp type, the emitter of the drive transistor Tr2 must be connected to the base of the control transistor Tr1. become.

The release transistor Tr3 has a base connected through a resistor R7 to a signal output section O1 of the microcomputer MPU, an emitter connected to a common connection cathode of both backflow prevention diodes D1 and D2, and a collector connected to ground. Has been done.

In the seismic switch SW, one contact a is connected to the battery power source E and the other contact b is connected to the signal input section I2 of the microcomputer MPU. A noise absorption circuit configured by a parallel circuit of a resistor R1 and a capacitor C1 is connected between the other contact b of the seismic switch SW and the ground.

In such a configuration, the control transistor Tr1 is in a non-conducting state, and the power input section I1 of the microcomputer MPU is not supplied with power from the battery power source E, so that there is an earthquake and the seismic switch is activated. SW
When the contacts a and b are closed and turned on, the base of the drive transistor Tr2 is connected to the battery power source E via the seismic switch SW.
Is supplied, the drive transistor Tr2 becomes conductive. When the drive transistor Tr2 becomes conductive, the control transistor Tr1 also becomes conductive. As a result, the battery power E is supplied to the power supply input section I1 of the microcomputer MPU, and the microcomputer MPU becomes operable.

When the microcomputer MPU becomes operable, the power to the power input section I1 is fed back to the drive transistor Tr2 via the backflow prevention diode D1.
Even if W repeatedly turns on and off due to an earthquake, the conductive state is maintained regardless of the behavior of the seismic switch SW, and as a result, the power supply control transistor Tr1 also maintains the conductive state.

In this way, when the seismic switch SW is turned on once due to an earthquake, the microcomputer M
The power is automatically supplied to the PU, and thereafter, the power is continuously supplied. Therefore, the microcomputer MPU takes in a seismic signal generated by turning on / off the seismic switch SW from the signal input section I2 to perform seismic observation. By performing signal processing, a required output is output from the output section O2 to a gas circuit breaker (not shown), whereby the gas circuit breaker operates and it is possible to avoid a danger due to an earthquake.

Next, when stopping the supply of power, the microcomputer MPU outputs a power supply stop signal from the signal output section O1 to turn on the release transistor Tr3, so that the drive transistor Tr2 is turned off. As a result, the control transistor Tr1 becomes non-conductive, the battery power source E and the power source input section I1 are disconnected, and the power supply to the microcomputer MPU by self-holding is released. Second Embodiment FIG. 2 is a circuit diagram of a power supply control circuit according to a second embodiment of the present invention and a micro-type vibration sensor whose power supply is controlled by the power supply control circuit. Example 1
In addition to the function of the seismic switch SW to turn on and off in response to an earthquake, the microcomputer MP
A plurality of seismic switches SW1 to SW1 in the second embodiment have a function as a switch for turning on power to U.
The SWn functions as a switch for turning on and off in response to an original earthquake, and is characterized in that a trigger switch TSW is provided separately as a switch for turning on the power. In addition, a microcomputer MP is provided corresponding to each of these seismic switches SW1 to SWn.
A plurality of signal input units I21 to I2n are provided in U.

In the power supply control circuit of the second embodiment,
As in the first embodiment, by turning on the trigger switch TSW, the drive transistor Tr2 is made conductive, and thereby the control transistor Tr1 is made conductive to supply power to the power input unit I1 of the microcomputer MPU, After supplying power to the power input section I1, the power supplied to the power input section I1 is applied to the driving transistor T.
It feeds back to the base of r2 to self-hold the supply.

In this way, even in the second embodiment, as in the first embodiment, the battery power E is not consumed until the trigger switch TSW is turned on and the power is supplied to the microcomputer MPU. Therefore, low power consumption can be achieved in the battery-powered micro-type vibration sensor.

[0030]

As is apparent from the above description,
In the power supply control circuit according to claim 1 of the present invention,
When the switch is turned on, the drive transistor conducts and, as a result, the control transistor also conducts, so that the power input of the circuit is connected to the power supply, the circuit is in the operating state, and the power input of the circuit is Since it is connected to the base of the drive transistor, the power supplied to the power supply input section is fed back to the base of the drive transistor, and as a result, the drive transistor is in a conductive state even when the switch is off,
That is, the control transistor is also kept conductive. Therefore, in the power supply control circuit according to the first aspect, when the control transistor is in the non-conducting state, the power is not supplied to the power input section of the circuit, so that the power is not consumed. Then, power is supplied to the power input section only after the switch is turned on, and once the switch is turned on and power is supplied to the power input section, even if the switch is turned off, the power is not supplied. Power is continuously supplied to the input section.

In the second and third aspects of the present invention, the power supply control circuit according to the first aspect makes it possible to obtain a micro-type vibration sensor with low power consumption.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a second embodiment of the present invention.

FIG. 3 is a circuit diagram of a conventional example.

[Explanation of symbols]

 E Battery Power Supply MPU Microcomputer Tr1 Control Transistor Tr2 Drive Transistor SW, SW1 to SWn Seismic Switch TSW Trigger Switch

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication location H02J 1/00 307 A 6447-5G 7/00 302 A 9060-5G H03K 17/60

Claims (3)

[Claims] 1. A control transistor (Tr1) and a drive transistor (Tr2) are provided. The control transistor (Tr1) has a collector / emitter, a power supply input section (I1) and a power supply (E1) of a circuit (MPU). )
And the base is connected to the collector or emitter of the drive transistor (Tr2), and the base of the drive transistor (Tr2) is connected to the circuit (MP
A power supply control circuit, which is connected to a power input unit (I1) of U) and a power supply (E) via a switch (SW). 2. A circuit (MP) driven by a battery power source (E).
U) and the power supply control circuit according to claim 1, and a seismic switch (SW) as the switch (SW). . 3. A circuit (MP) driven by a battery power source (E).
U) and the power supply control circuit according to claim 1, a trigger switch (TSW) as the switch (SW), and a seismic switch (SW1 to SWn). Is a battery power source (E) and circuit (MPU)
And a signal input unit (I21 to I2n) of the micro type seismoscope.