JPH02217098A - Power unit turning-on circuit - Google Patents

Abstract

PURPOSE:To reduce the number of core wires of a cable wiring between a master equipment and an operation section and to reduce the entire cost of a radio terminal equipment by providing a current detection circuit detecting a prescribe load current of an operating section flowing to the wiring of the master equipment. CONSTITUTION:A master equipment 2 is provided with a current detection circuit 21 connecting to an operating section 3 and detecting a prescribed load current I3 of the operating section 3 flowing to wiring 4 supplying a power unit voltage Vc from a power unit 1 to the operating section 3 via the master equipment 2, and the current detection circuit 21 of the master equipment 2 detects the load current I3 of the operating section 3 through the wiring 4 supplying the power voltage Vc to the operating section 3 only with a power unit switch circuit 32 turned on resulting from turning-on of a power unit application switch 31 of the operating section, drives the detection output to the drive a power unit switch 22 of the master equipment 2 to close the path to a master equipment circuit 23 thereby causing the load current I3 to flow. Thus, the wiring 4 tying the master equipment 2 and the operating section 3 is a simple wiring comprising power unit lines Vc, G only.

Description

[Detailed Description of the Invention] [Summary] It consists of an operation unit (control unit) that controls the main device (transceiver unit) from a remote location, such as a wireless terminal of a car phone, and wiring that connects both units. The power supply switch supplies a predetermined load current (2) from the power supply directly connected to the main device to the load circuit of the main device via the power switch circuit of the main device, and supplies a predetermined load current (I3) to the load circuit of the operating section through the wiring. Regarding the power-on circuit that supplies power, the wiring between the main device and the operating section eliminates the need for the conventional power-on switch on/off signal transmission line to the main device, and only the power supply line from the main device to the operating section. , the purpose of this is a power-on circuit that can supply a predetermined current to the load circuit of the main device and the operating section, and a current detection circuit that detects the predetermined load current I3 of the operating section that flows from the power supply to the wiring between the main device and the operating section. The current detection circuit of the main device detects the load current I3 of the operating section flowing through only the power supply line Vc from the main device to the operating section when the power switch circuit of the operating section is turned on. A power switch circuit of the device is configured to cause a predetermined load current I2 to flow from the power source to the load circuit of the main device.

[Industrial application field]

The present invention consists of an operating unit (control unit) that controls a main device (transceiver unit) from a remote location, such as a wireless terminal of a car phone, and wiring that connects the two.
A power supply that supplies a predetermined current I2 from a power source directly connected to the main device via a power switch circuit to the load circuit of the main device using a power-on switch of the operating section, and supplies a predetermined load current I3 to the circuit of the operating section through the wiring. Regarding the input circuit.

[Conventional technology]

Conventionally, the above power-on circuit, as shown in the block diagram of FIG. 5, connects a power supply switch 21 that supplies a predetermined load current (2) from a power source IA directly connected to the main device 2A to the transceiver circuit 238 of the main device 2A. When opening/closing is performed using the power supply switch 31^ of the operation section static, a line Vc for supplying power to the operation section 38 is connected to the wiring 4A connecting the main device 28 and the operation section 3A;
In addition to G, a separate line C0NT is provided for transmitting the on/off signal C representing on/off of the power on switch 31^ from the operating section 38 to the main device 2A.

[Problems to be Solved by the Invention] The wiring 48 connecting the main device/device 2A and the operation section 3A is
-i is quite long, and in the conventional example, the number of core wires of the wiring is increased in order to turn on the power of the main device 2A, so the wiring 4A including the connectors at both ends, wiring cables, etc.
There were problems in that it was expensive and required a large space. The present invention provides wiring 4 connecting between the main device 2 and the operating section 3.
However, when the power supply switch 31A of the conventional operation unit is turned on/
The transmission line C0NT for the disconnection signal C to the main device 28 is not required, and the wiring 4 of only the power supply lines Vc and G from the main device 2 to the operating section 3 connects the load circuit 23 of the main device 2 and the operating section. 3
A predetermined load current I2. An object of the present invention is to provide a power-on circuit that supplies I3.

[Means to solve the problem]

As shown in FIG.
The main device 2 includes a current detection circuit 21 that detects a predetermined load current I3 of the operating section 3 flowing through a wiring 4 connected to the power source 1 and supplying the power supply voltage Vc from the power source 1 to the operating section 3 via the main device 2. When the current detection circuit 21 turns on the power switch circuit 32 by turning on the power supply switch 31 of the operation unit 3,
The load current I3 flowing to the load circuit 33 of the operation section 3 through the wiring 4 that only supplies the power supply voltage Vc to the operation section 3 is detected, and the detected output drives the power switch 22 of the main device 2 to control the main device circuit 23. This is solved by the present invention, which is configured to turn on the path to and conduct a predetermined load current I2.

1 is directly connected to the main device 2, and the main device circuit 23 of the main device 2
This is the original power source that supplies a predetermined load current I2 to the main device 2 and a predetermined load current I3 to the circuit 33 of the operating section 3 through the wiring 4 that connects the main device 2 and the operating section 3.

2 is a main device that is directly connected to the power source 1 and connected to the operating section 3 via wiring 4, and includes a current detection circuit 21, a power switch circuit 22. The current detection circuit 21 is composed of a main device circuit 23, and a load current 1. 1 is detected, and the power switch 22 is driven by the detection output to turn on the path to the load circuit 23 of the main device and cause a predetermined load current 2 to flow through the load circuit 23 of the main device.

3 is an operation unit connected to the main device 2 via wiring 4, and includes a power-on switch 31. Power switch circuit 32. Consisting of an operation section circuit 33, a power switch circuit 3 of the operation section 3
2 turns on the power supply switch 31 to turn on the path of the power supply wiring 4 from the main device 2 to the operating section circuit 33 of the operating section 3, and causes a predetermined load current I3 to flow through the operating section circuit 33.

4 is a wiring that connects the main device 2 and the operating section 3 and supplies the power supply voltage Vc from the power source 1 to the operating section 3; This wiring is connected to the power switch circuit 32 of the operating section 3 via the current detection circuit 21, and only supplies power to flow a predetermined load current (3) to the operating section circuit 33 when the power switch circuit 320 of the operating section 3 is turned on. .

When the current detection circuit 21 of the main device 2 turns on the power switch circuit 32 by turning on the power supply switch 31 of the operation section 3, a load current 13 flows from the power supply 1 through the wiring 4 to the operation section circuit 33 of the operation section 3. is detected, and by turning on the power switch 22 of the main device 2 based on the detection output, the path from the power source 1 to the main device circuit 23 of the main device 2 is turned on, and a predetermined load current I2 is caused to flow.

[Effect]

The power source 1 is directly connected to the main device 2 and passes a predetermined load current I2 to the main device circuit 23 via the power switch 22 of the main device 2. The main device 2 is further connected to the operating section 3 via a wiring 4. Ru. That is, the current detection circuit 21 of the main device 2 is connected to the power switch circuit 32 of the operating section 3 through the wiring 4. Then, when the power switch circuit 32 is turned on by turning on the power supply switch 31 of the operation section 3, the current detection circuit 21 of the main device 2 is connected to the operation section of the operation section 3 from the power source 1 through the current detection circuit 2I of the main device 2. The load current I3 flowing to the circuit 33 is detected, and the detected output is used to switch the power switch 22 of the main device 2.
By turning on the path from the power supply 1 to the main device circuit 23 of the main device 2, the path from the power supply 1 to the main device circuit 23 of the main device 2 is turned on.
A predetermined load current I2 is applied to the terminal.

The wiring 4 is a wiring that only connects the main device 2 and the operation section 3 and supplies the power supply voltage Vc from the power supply 1 to the operation section 3, and is used to supply the power supply voltage Vc of the power supply I directly connected to the main device 2. It is connected to the power switch circuit 32 of the operating section 3 via the current detection circuit 21 of the main device 2, and supplies a predetermined load current I to the operating section circuit 33 when the power switch circuit 32 is turned on.

Therefore, in the power-on circuit of the present invention, the wiring connecting the main device 2 and the operating section 3 is the wiring 4 that only supplies power, and the conventional power-on switch 31 receives the on/off signal C from the operating section 3A to the main device 2A. Wiring 4 of only power supply lines Vc and G from the main device 2 to the operation unit 3 becomes unnecessary.
As a result, a load current ■2 from the power supply 1 to the load circuit 23 of the main device 2 and a predetermined load current I3 to the load circuit 33 of the operation unit 3
The power supply can be turned on/off. Therefore, main device 2
The wiring 4 connecting between the and the operating section 3 becomes a simple wiring consisting of only the power supply lines Vr, . . . G, and the problem is solved.

〔Example〕

FIG. 2 is an in-vehicle connection diagram of a wireless terminal of a mobile phone showing the configuration of a power-on circuit according to an embodiment of the present invention, and FIG. 3 is a circuit diagram showing the configuration of the first embodiment. FIG. 4 is a circuit diagram of the second embodiment.

In the in-vehicle connection diagram shown in Fig. 2, the wireless terminal of the car phone is generally installed with the transceiver unit of the main device 2 installed in the trunk of the car, and the telephone (control unit) of the operation unit 3 installed in the driver's seat. Connection cable wiring 4 is provided for sending and receiving various signals and for supplying power supply voltage Vc from battery 1. Since the wiring 4 is quite long, reducing the number of core wires has a large impact on the overall cost.

The circuit diagram of the first embodiment shown in FIG. 3 is an example in which the present invention is implemented in the simplest manner, and the current detection circuit 21 and power switch circuit 22 of the main device 2 are connected to the transistor TR resistor R+, the resistor R
When the power switch 32 of the operation unit 3 is turned on, the load current (2) of the load circuit causes a potential difference between both ends of the resistor R, to turn on the transistor TR.
A predetermined load current I2 is supplied from the collector output to the load circuit 23 of the main device, and the resistor R2 is connected to TR,
This is a resistor for limiting the Heas current.

The circuit diagram of the second embodiment in FIG. 4 shows the load circuit 2 of the main device 2.
The on/off switching characteristics of the path from the power supply 1 to the main device 2 are further improved.
1 and the power switch circuit 22 are composed of a transistor TR, a resistor R3, a resistor R2, a transistor TR2, a resistor R3, a resistor R4, a transistor TR3, a resistor R5, and a resistor R6, and the resistor R3 is the transistor TR.

The resistor R6 is a resistor for turning off the transistor TR2 when the transistor TI is turned off.
? 2. A resistor for limiting the Heas current of T113,
The resistor R5 is a resistor for preventing breakdown of the Heath emitter withstand voltage of the transistor TR.

In both the first embodiment shown in FIG. 3 and the second embodiment shown in FIG. There is no problem because the number can be reduced by one compared to the conventional example.

[Brief explanation of the drawing]

Fig. 1 is a principle diagram showing the configuration of the power-on circuit of the present invention, Fig. 2 is an in-vehicle connection diagram of a car phone showing the configuration of the power-on circuit of the embodiment of the present invention, and Figs. FIG. 5 is a circuit diagram showing the configuration of a power-on circuit according to a first embodiment and a second embodiment of the invention, and FIG. 5 is a block diagram of a conventional power-on circuit. In the figure, TB [Effects of the Invention] As explained above, according to the power-on circuit of the present invention, -
The number of core wires in the cable wiring between the main device and the operation unit, which is long when fishing on a boat, can be reduced by one, so the size of the cable wiring connector and the mounting space can be reduced, reducing the overall size of the wireless terminal. The effect of reducing costs can be obtained.

Claims (1)

[Claims] Consists of a main device (2), an operating section (3) for controlling the device from a remote location, and wiring (4) connecting both (2, 3), and a power source for the operating section (3). A predetermined load current is supplied via a power switch circuit (22) that turns on/off a path from a power supply (1) directly connected to the main device (2) to a load circuit (23) of the main device (2) by a turn-on switch (31). (I_2) and the predetermined load current (I
In the power-on circuit that supplies power to the main device (2)
) is equipped with a current detection circuit (21) that detects a predetermined load current (I_3) of the operating section (3) flowing through the wiring (4), and when the power switch circuit (32) of the operating section (3) is turned on,
The load current (I_3) of the operation unit (3) that the current detection circuit (21) of the main device (2) flows through the wiring (4) that only supplies power
1. A power-on circuit characterized in that a power source (1) causes a predetermined load current (I_2) to flow to a load circuit (23) of a main device.