JPH09284113A - Dc load drive circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drive plural DC loads whose operating voltage and operating timing are different through a simple drive circuit configuration. SOLUTION: Plural DC loads are connected to one drive transistor(TR) 1 and an operation control circuit 16 is used to turn on/off each switching circuit in a designated timing depending on an operating timing of the DC loads so as to select a negative level of the loads. A resistor is connected between a negative point of the respective DC loads and a base of the drive TR 1 to control simultaneously the load switching and the operating level of the drive TR 1. In this case, the operating level is decided by the set resistance and a desired voltage is applied to the respective DC loads to allow the loads to be driven.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pager and a mobile phone, and more particularly to a DC load drive circuit for applying different voltages to a plurality of DC loads to operate them.

[0002]

2. Description of the Related Art Conventionally, when driving a DC load, various types and methods of DC load drive circuits have been employed in order to stably supply the operating voltage of the DC load. Among these, a plurality of DC loads having different drive voltages may be operated in one device. In particular, a vibration motor for confirming the arrival of radio waves, which consists of a DC motor for vibration that shifts the center of gravity of a weight used in pagers and mobile phones to generate vibration, and a magnetic motor that operates by the excitation effect of DC voltage application. The buzzer for incoming calls, which is composed of a sounding body, is driven as a DC load. An example of the conventional DC load drive circuit described above will be described below with reference to the drawings.

FIG. 4 is a block diagram showing an example of how to use a conventional DC load drive circuit. In FIG. 4, power is supplied from the power supply circuit 2 to drive the first DC load 24 and the second DC load 25. At this time, the first DC load drive circuit 20 (or the regulator circuit) is connected to each pair of the first DC load 24 and the second DC load 25.
And a second DC load drive circuit 21 (or a regulator circuit) are arranged so that the first DC load 24 and the second DC load 2
The configuration is such that an optimum and stable voltage is applied to the unit 5 and stable power supply is performed at the same time. In addition, the first DC load 2
The first switching circuit 22 and the second switching circuit 23 corresponding to the first DC load 24 and the second DC load 25, respectively, for turning on and off the operating states of the fourth DC load 25 and the second DC load 25 Yes, and is controlled by the operation control circuit 16 to perform the switching operation at the specified operation timing for operating each DC load,
The switching operation is configured to supply and cut off power to the DC load. Regarding the switching operation, the first DC load drive circuit 20 (or the regulator circuit) and the second DC load drive circuit 21 are arranged without the switching circuit arrangement as shown in FIG.
There is also a configuration in which the operation of (or a regulator circuit) is directly turned on and off to perform a switching operation.

[0004]

In such a DC load drive circuit, when a plurality of DC loads having different drive voltages are operated in one device, a DC load corresponding to the number of DC loads having different drive voltages is operated. Each requires a drive circuit (or regulator circuit), which has been a factor in increasing the cost of the device. Also, if power is supplied directly from the power supply circuit by configuring a resistor or Zener diode without using a DC load drive circuit (or regulator circuit), it will be difficult to maintain stable voltage application and stable power supply. there were. Furthermore, when it was attempted to control the operating state of the DC load by switching the voltage applied to the DC load, it was necessary to add a complicated control circuit.

The present invention controls the operation timings of a plurality of DC loads having different drive voltages, and simultaneously switches the operation of the DC loads and the potential control means, so that a DC transistor having a single drive transistor and a simple configuration can be used. The purpose of the invention is to provide a load driving circuit. Another object of the present invention is to provide a DC load drive circuit capable of controlling the operating state of a DC load by adding a simple circuit.

[0006]

In order to solve this problem, a DC load drive circuit according to the present invention provides a drive circuit section composed of a drive transistor for supplying a voltage to a DC load and a DC load control circuit. A plurality of potential control means for determining the operating potential of the drive transistor, an operation control circuit having a function of sending a switching control signal in accordance with the operation timing of the DC load, and a DC signal receiving a signal from the operation control circuit. The basic configuration is to include a plurality of switching circuits that perform switching operations for controlling the load operation and the potential control means.

In the first configuration, a general DC load is driven based on the basic configuration. In the second configuration, in addition to the basic configuration, a plurality of DC load applied voltages are applied from the operation control circuit. The third configuration includes an attenuator control unit that receives the control signal for switching the stage and determines the operating potential of the drive transistor. In the third configuration, a radio wave is received based on the basic configuration and a signal data on the radio wave is decoded. For confirming the arrival of radio waves, which is composed of a circuit section, a receiver control section that manages the operating state of the receiving circuit section under the control of the operation control circuit, and a vibration DC motor that shifts the center of gravity of the weight to generate vibration And a buzzer for ringing an incoming call, which is composed of a magnetic sounding body that operates by an excitation type effect by applying a DC voltage.

Thus, in the first configuration, the operation control circuit simultaneously controls the operation of the first DC load and the first potential control means according to the operation timing of the DC load, or the second control. By controlling the operation of the DC load and the second potential control means at the same time, one drive circuit for operating the first DC load or the second DC load at the optimum supply voltage or operation timing is provided. It can be easily configured with the drive transistor.

In the second configuration, a control signal for switching the applied voltage of the DC load from the operation control circuit in a plurality of steps is received, the attenuator control means determines the operating potential of the drive transistor, and the applied voltage of the DC load is determined. Can be switched in a plurality of steps to control the operating state of the DC load. In the third configuration, the operation control circuit controls so that the operation timings of the receiving circuit operation, the vibration motor operation, and the buzzer operation do not overlap, and the motor and the buzzer operate at the optimum supply voltage and operation timing. At the same time, by stopping the operation of the receiving circuit during the operation of the motor and buzzer, the power supply circuit is prevented from overloading and malfunction due to noise jumping into the antenna and receiving circuit caused by the operation of the motor and buzzer is prevented. It can be prevented.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a drive circuit section composed of a drive transistor for supplying a voltage to a DC load, and a first circuit to which electric power is supplied from the drive circuit section. A DC load, a second DC load supplied with power from the drive circuit section, and a first potential for determining an operating potential of a drive transistor of the drive circuit section according to control of the first DC load. Control means, second potential control means for determining the operating potential of the drive transistor of the drive circuit section according to the control of the second DC load, and sending a switching control signal according to the operation timing of the DC load And a first switch that receives a signal from the operation control circuit and performs a switching operation for controlling the operation of the first DC load and the first potential control means. The A circuit, and a second switching circuit that receives a signal from the operation control circuit and performs a switching operation for controlling the operation of the second DC load and the second potential control means. According to the operation timing of the DC load by the circuit, by operating the first switching circuit or the second switching circuit, to simultaneously control the operation of the first DC load and the first potential control means, Alternatively, the operation of the second DC load and the second potential control means are controlled at the same time, and at the optimum supply voltage or operation timing for each of the first DC load or the second DC load. This has the effect that the drive circuit to be operated can be easily configured with one drive transistor.

According to a second aspect of the present invention, there is provided a drive circuit section including a drive transistor for supplying a voltage to a DC load, a first DC load supplied with power from the drive circuit section, and the drive circuit. A second DC load supplied with electric power from the unit, a first potential control unit for determining an operating potential of the drive transistor of the drive circuit unit according to the control of the first DC load, and a second Second potential control means for determining the operating potential of the drive transistor of the drive circuit section according to the control of the DC load, the function of sending a switching control signal according to the operation timing of the DC load, and the application of the DC load An operation control circuit having a control function of switching the voltage in a plurality of steps, and a switch for receiving a signal from the operation control circuit and controlling the operation of the first DC load and the first potential control means. A first switching circuit that performs a switching operation, and a second switching circuit that receives a signal from the operation control circuit to control the operation of the second DC load and the second potential control means. A switching circuit and an attenuator control means for determining an operating potential of the drive transistor by receiving a control signal for switching the applied voltage of the DC load from the operation control circuit in a plurality of steps, and applying the DC load from the operation control circuit. The attenuator control means receives the control signal for switching the voltage in a plurality of steps, and the operating potential of the drive transistor can be determined by the attenuator control means. It has the effect of being controllable.

The invention according to claim 3 is a receiving circuit section for receiving an electric wave and decoding the signal data on the electric wave, and a receiving section for controlling the operating state of the receiving circuit section under the control of the operation control circuit. A machine control unit, a drive circuit unit configured by a drive transistor that supplies a voltage to a DC load, and a vibration motor for confirming an incoming radio wave that is configured by a vibration DC motor that shifts the center of gravity of a weight to generate vibration, A buzzer for incoming call composed of a magnetic sounding body that operates with an excitation effect by applying a DC voltage, a potential control means that determines an operating potential when the vibration motor operates, and an operation when the buzzer operates. A potential control unit that determines a potential, sends a switching control signal according to the operation timing of the vibration motor and the buzzer, and manages the operating state of the receiving circuit unit. An operation control circuit having a function, a first switching circuit that receives a signal from the operation control circuit, and performs a switching operation for controlling the operation of the vibration motor and the potential control means for the vibration motor, A second switching circuit that receives a signal from the operation control circuit and performs a switching operation for controlling the operation of the buzzer and the buzzer potential control means, and switching of the vibration level of the vibration motor from the operation control circuit. An attenuator control means for receiving the control signal corresponding to the switching of the sound pressure level of the buzzer to determine the operating potential of the drive transistor is provided, and the operation control circuit superimposes the operation timing of the receiving circuit operation, the vibration motor operation, and the buzzer operation. Control so that the first switching circuit or the second switching circuit operates. The operation of the vibration motor and the potential control means for the vibration motor are controlled at the same time, or the operation of the buzzer and the potential control means for the buzzer are controlled at the same time, and the motor and the buzzer are operated at the optimum supply voltage and operation timing. At the same time, it is configured to stop the operation of the receiving circuit during the operation of the motor and buzzer to prevent the power circuit from overloading and to prevent noise from jumping into the receiving circuit caused by the operation of the motor or buzzer. This has the effect of preventing malfunction due to

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3. (Embodiment 1) FIG. 1 is a circuit block diagram of a DC load drive circuit according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 is a drive transistor for supplying electric power to a DC load, 2 is a power supply circuit of a device formed by a battery or a DC / DC converter, and 4 is a vibration that shifts the center of gravity of a weight to generate vibration. A vibration motor for confirming incoming radio waves, which is composed of a DC motor for the incoming call, 5 is a buzzer for incoming call which is composed of a magnetic type sounding body which operates by an excitation type effect by applying a DC voltage, and 6 is a vibration level of the vibration motor. Switching transistor for switching the attenuator operation for switching or switching the sound pressure level of the buzzer, 7 is a switching transistor for switching the drive of the vibration motor, 8 is a switching transistor for switching the drive of the buzzer, and 9 is a drive transistor. A resistor for applying a voltage to 10 is a potential control hand for a vibration motor , 11 is a resistance as a buzzer potential control means, 12 is a backflow prevention diode for preventing backflow from the drive transistor to the power source, 13 is a discharge diode for discharging the back electromotive force of the motor, and 14 is Discharge diode for discharging the counter electromotive force of the buzzer, 15
Is a variable resistor for switching the operating potential of the drive transistor in a plurality of steps for switching the vibration level of the vibration motor and the sound pressure level of the buzzer, and 16 is an operation control circuit for controlling the switching transistor 6, the switching transistor 7, and the switching transistor 8. Reference numeral 17 is an attenuator circuit composed of a switching transistor 6 and a variable resistor 15, 18 is a receiving circuit section for receiving a radio wave and decoding a data signal on the radio wave, and 19 is a control signal from an operation control circuit. The receiver control unit 26, which manages the operating state of the circuit unit, comprises an antenna for receiving radio waves.

The operation of the DC load drive circuit configured as described above will be described below. A radio wave in which paging information as a pager or data of an incoming call signal as a mobile phone is modulated is received by an antenna 26, and a receiving circuit section 18 performs a radio wave tuning operation or amplification as in a general receiver. It operates to detect various data signals modulated on the radio wave and send them to the receiver controller 19. The receiver control unit 19 processes various detected data signals, manages the operation state of the receiving circuit unit 18, and controls the receiving circuit such as switching the power supply of the receiving circuit unit 18 and sending out tuning data. To do. Further, the receiver control unit 19 is configured to mutually control the operation control circuit 16. Because it is in one device,
It is also possible to configure the receiver control unit 19 and the operation control circuit 16 with a single microcomputer to make full use of the control.

The receiver control unit 19 controls the receiving circuit unit 18, and the operation control circuit 16 controls the switching transistor 6, the switching transistor 7, and the base voltage of the switching transistor 8 according to the contents of the device operation setting and the contents of the received data. The operation timing and the voltage state of each portion will be described later in detail with reference to a timing chart.

Usually, switching transistor 6, switching transistor 7, switching transistor 8
Is controlled to be in an OFF operation state, and voltage is applied to the base of the drive transistor, but power is not supplied, and no voltage is applied to the vibration motor 4 or the buzzer 5. At this time, when some operation is performed and the vibration motor 4 is operated, the operation control circuit 16 turns on the switching transistor 7. When the switching transistor 7 is turned on, the base voltage of the drive transistor 1 becomes a voltage value obtained by dividing the power supply voltage by the constants of the resistors 9 and 10, and the emitter voltage of the drive transistor 1 is lower than the base voltage by VBE. Is output. Further, in the vibration motor 4, the minus terminal side becomes almost 0 potential (actually, the potential higher by VCE of the switching transistor 7) and the plus terminal side becomes the emitter potential of the driving transistor 1, and this potential difference is applied to the motor to rotate. To start. By setting the constants of the resistor 9 and the resistor 10 to the optimum constants, the optimum voltage can be applied to the vibration motor 4 and the overvoltage may be applied to cause destruction, or conversely, the voltage does not start below the starting voltage to start rotation. It is possible to prevent the problem of sticking. Next, when the switching transistor 7 is turned off to stop the vibration motor 4, the base voltage of the drive transistor 1 returns to a state in which the voltage is initially applied by the resistor 9 but no power is supplied. Vibration motor 4
Is a DC load, but since the counter electromotive force remains because it is composed of a coil, the discharge diode 13 discharges the counter electromotive force.

When the buzzer 5 is operated by some operation, the same operation as the operation of the vibration motor 4 is performed. At this time, the switching transistor 8 operates as the switching transistor 8, the resistor 11 operates as the resistor 11, and the discharging diode 13 operates as the discharging diode 14.
It goes without saying that the voltages applied to the vibration motor 4 and the buzzer 5 can be set to optimum values for each by setting 1 separately. The buzzer 5 uses a magnetic sounding body that operates by an exciting effect for the purpose of obtaining a high sound pressure. Therefore, when driving the buzzer, continuous square wave voltage application is required. In this case, the control signal output from the operation control circuit 16 to the switching transistor 8 is square-wave controlled at a frequency that determines the sound quality of the buzzer, so that the drive transistor 1 can be easily operated.
The operation of can be performed.

The attenuator circuit 17 is driven in order to change the amount of vibration of the vibrating motor 4 in operation and to set or change the volume of the buzzer 5. The case where an attenuator circuit is added will be described below. The basic operation is based on the operation already described. When trying to operate the vibration motor 4, the switching transistor 7 is turned on, and in synchronization with this, the switching transistor 6 is turned on. The variable resistor 15 is set to an arbitrary value that has already been set, and the base voltage of the drive transistor is determined by the constants of the resistors 9, 10 and the variable resistor 15, that is, the operating voltage of the vibration motor 4 is set freely. Therefore, the vibration amount generated by the vibration motor 4 can be controlled in a plurality of steps with a simple configuration of the attenuator circuit 17. Similarly, buzzer 5
Even when the buzzer 5 is being driven or the buzzer 5 is being driven, an arbitrary sound pressure can be obtained by controlling the voltage applied to the buzzer in a plurality of steps. Switching Transistor Switching transistor 6 and switching transistor 7, or switching transistor 6 and switching transistor 8 are not interlocked with the control, but there is no problem in operation, but the resistance 9 is used to flow to the attenuator circuit. It is proposed to control the operation timing to reduce the current. The operation timing and the voltage state of each part at this time will be described later in detail using a timing chart.

Depending on the method of constructing the attenuator circuit, a state in which a voltage higher than the power supply voltage is applied to the base of the drive transistor 1 may occur, or in the circuit shown in the second embodiment, the base voltage of the drive transistor 1 is higher than the collector voltage. The backflow prevention diode 12 is inserted in the case where a voltage is applied. Drive transistor 1
If the base voltage of is not higher than the collector voltage,
The backflow prevention diode 12 may be omitted.

FIG. 2 shows a timing chart of the operation of the DC load drive circuit according to the first embodiment of the present invention.
The operation timing will be described below with reference to FIGS. Here, first, a case will be described in which the device operation setting when an incoming call is called is set to operate both the vibration motor 4 and the buzzer 5. Reception circuit unit 18,
Incoming data is taken out by the receiver control unit 19 as shown in FIG. When there is incoming data, the receiver control unit 19 stops the operation of the receiving circuit unit 18 during the vibration motor control period and the buzzer control period as shown in FIG. Let As a result, it is possible to prevent malfunction due to noise jumping into the receiving circuit unit 18 or the antenna 26, which occurs due to the operation of the motor or the buzzer. At the same time as the operation of the receiving circuit unit 18 is stopped,
As shown in (c), the operation control circuit 16 applies a voltage to the base of the switching transistor 7 for the period of driving the motor. Therefore, the switching transistor 7 is O
The N state is reached, and the applied voltage of the vibration motor 4 is the same as the motor applied voltage of FIG. Next, when the control voltage shown in FIG. 3 (c) becomes L, the voltage shown in FIG. 3 (d) is applied to the base of the switching transistor 8, and the applied voltage of the buzzer 5 is the buzzer applied in FIG. 3 (f). It becomes the corner of the voltage. In this embodiment, since the magnetic speaker which operates by the excitation effect is used, the driving is performed by applying a continuous square wave as shown in FIG. 3 (d). Buzzer 5
When the driving period of (3) is finished, the operation of the receiving circuit unit 18 is restarted as shown in FIG.

Next, the operation timing of the attenuator circuit 17 will be described. A case where the device operation setting at the time of calling an incoming call is set so that only the buzzer 5 operates and the sound pressure of the buzzer becomes lower will be described on the right side of FIG. As described above, when there is incoming data, the operation of the receiving circuit unit is stopped and the voltage shown in FIG. 3D is applied to the base of the switching transistor 8. At this time, since it is set to operate the attenuator, the operation control circuit 16 applies the voltage shown in FIG. As described above, it is desired that the waveforms of FIG. 3D and the waveform of FIG. 3G have the same timing. When the switching operation is performed, the buzzer applied voltage shown in FIG. The applied voltage value at this time is the attenuator circuit 17
Will be different from the value when is not working.

As described above, according to the present embodiment, a simple DC load drive circuit composed of a single drive transistor drives a plurality of DC loads driven by different vibration motors and buzzers at different operating voltages. It is possible to operate with an optimum supply voltage and operation timing. Further, by adding a simple attenuator circuit to this DC load drive circuit, it becomes possible to control the operating state of the DC load by switching the applied voltage of the DC load in a plurality of steps.

(Embodiment 2) Next, FIG. 3 shows a circuit block diagram of a DC load drive circuit to which the stabilizing circuit of the second embodiment is added, and in FIG. In addition to the basic configuration of FIG. 1, 27 is a stabilizing circuit composed of a DC / DC converter and a regulator capable of supplying a stable voltage, and 3 is a battery.

The operation of the DC load drive circuit configured as described above will be described below. Typically,
In portable devices such as pagers and mobile phones, power is supplied by batteries. Therefore, the voltage of the battery may fluctuate or the voltage may drop, and the voltage applied to the load may fluctuate.

First, a stable voltage is applied to the driving transistor 1 from the stabilizing circuit 27, which is composed of a DC / DC converter or a regulator and can supply a stable voltage, through the resistor 9 which supplies the voltage to the driving transistor 1. As described above, the base voltage of the drive transistor 1 is determined by the resistors 9 and 10 when the vibration motor 4 is operating, and by the resistors 9 and 11 when the buzzer 5 is operating. Since the supplied voltage is constant, the voltage applied to the vibration motor 4 and the buzzer 5 becomes constant even if the voltage of the battery 3 changes, and stable vibration and buzzer sound pressure can be obtained.
Even when the voltage of the battery 3 drops, a stable drive voltage can be applied up to the voltage required to drive the DC load and the voltage obtained by adding VCE of the drive transistor 1.

Strictly speaking, the base voltage of the driving transistor 1 is influenced by not only the constants of the resistors 9 and 10 or the resistors 9 and 11 but also the base current of the driving transistor 1. That is, it is very difficult to determine the base voltage of the driving transistor 1 based on the calculated value. Therefore, the transistor used for the driving transistor 1 should have a very high direct current amplification factor, or the resistors 9, 10 and 11 should be set to the lowest possible constants so as to be affected by the base current of the driving transistor 1. We need to make it harder. In the actual setting, it is recommended to verify the load applied voltage with the actual circuit.

[0027]

As described above, according to the present invention, a drive circuit section including a drive transistor for supplying a voltage to a DC load and an operating potential of the drive transistor for controlling the DC load are determined. A plurality of potential control means, an operation control circuit having a function of sending a switching control signal according to the operation timing of the DC load, and a signal from the operation control circuit to control the operation of the DC load and the potential control means By providing a plurality of switching circuits for performing a switching operation to achieve this, it is possible to easily configure a drive circuit that operates a plurality of DC loads with optimum supply voltages and operation timings with a single drive transistor. Further, in addition to the basic configuration, by providing an attenuator control means for determining the operating potential of the drive transistor by receiving a control signal for switching the applied voltage of the DC load from the operation control circuit in a plurality of steps, a plurality of applied voltages of the DC load can be provided. The advantageous effect that the operating state of the DC load can be controlled by performing step switching is obtained. Furthermore, based on the basic configuration,
A receiver control unit that manages the operating state of the receiving circuit unit under the control of the operation control circuit is installed to operate multiple DC loads at the optimum supply voltage and operation timing for each, and at the same time, operate the DC load. By stopping the operation of the receiving circuit during the period, the overload state of the power supply circuit is prevented,
An advantageous effect is obtained in that it is possible to prevent malfunctions due to noise jumping into the receiving circuit section that occurs due to the operation of the DC load.

[Brief description of drawings]

FIG. 1 is a circuit block diagram of a DC load drive circuit according to an embodiment of the present invention.

FIG. 2 is a timing chart of the operation of the DC load drive circuit according to the embodiment.

FIG. 3 is a circuit block diagram of a DC load drive circuit to which the stabilizing circuit according to the second embodiment is added.

FIG. 4 is a block diagram showing an example of how to use a conventional DC load drive circuit.

[Explanation of symbols]

 1 Driving Transistor 2 Power Supply Circuit 3 Battery 4 Vibration Motor 5 Buzzer 6 Switching Transistor 7 Switching Transistor 8 Switching Transistor 9 Resistor 10 Resistor 11 Resistor 12 Backflow Prevention Diode 13 Discharge Diode 14 Discharge Diode 15 Variable Resistor 16 Operation Control Circuit 17 Attenuator circuit 18 Reception circuit unit 19 Receiver control unit 20 DC load drive circuit 1 (regulator circuit) 21 DC load drive circuit 2 (regulator circuit) 22 Switching circuit 1 23 Switching circuit 2 24 DC load 1 25 DC load 2 26 Antenna 27 Regulated power supply

Claims (3)

[Claims] 1. A drive circuit unit including a drive transistor for supplying a voltage to a DC load, a first DC load supplied with power from the drive circuit unit, and power supplied from the drive circuit unit. A second DC load, and a first potential control means for determining an operating potential of the drive transistor of the drive circuit section according to the control of the first DC load, and a second DC load according to the control of the DC load. Second potential control means for determining the operating potential of the drive transistor of the drive circuit section,
An operation control circuit having a function of sending a switching control signal in accordance with an operation timing of a DC load; an operation of the first DC load and a first potential control means for receiving a signal from the operation control circuit; A first switching circuit for performing a switching operation for controlling the operation, and a switching operation for receiving the signal from the operation control circuit and controlling the operation of the second DC load and the second potential control means. And a second switching circuit for performing, according to the operation timing of the DC load by the operation control circuit, by operating the first switching circuit or the second switching circuit, the operation of the first DC load and By simultaneously controlling the first potential control means or the operation of the second DC load and the second potential control means at the same time, DC load driving circuit, wherein a drive circuit for operating in an optimum supply voltage and operation timing respectively a DC load or a second DC load, constituted by a single drive transistor. 2. A drive circuit section including a drive transistor for supplying a voltage to a DC load, a first DC load supplied with power from the drive circuit section, and power supplied from the drive circuit section. A second DC load, and a first potential control means for determining an operating potential of the drive transistor of the drive circuit section according to the control of the first DC load, and a second DC load according to the control of the DC load. Second potential control means for determining the operating potential of the drive transistor of the drive circuit section,
An operation control circuit having a function of sending a switching control signal according to the operation timing of the DC load and a control function of switching the applied voltage of the DC load in a plurality of stages, and the first DC receiving the signal from the operation control circuit. A first switching circuit for performing a load operation and a switching operation for controlling the first potential control means; and a second DC load operation and the second switching operation for receiving a signal from the operation control circuit. And a second switching circuit that performs a switching operation for controlling the potential control means, and a control signal for switching the applied voltage of the DC load from the operation control circuit in a plurality of steps to determine the operating potential of the drive transistor. Attenuator control means for receiving a control signal for switching the application voltage of the DC load from the operation control circuit in a plurality of stages, The serial attenuator control means to determine the operating potential of the driving transistor, the DC load driving circuit according to claim 1, characterized in that can control the operation state of the DC load by switching a plurality of stages the voltage applied DC load. 3. A receiving circuit section for receiving a radio wave and decoding the signal data on the radio wave, and a receiver control section for managing the operating state of the receiving circuit section under the control of the operation control circuit.
A drive circuit section consisting of a drive transistor that supplies a voltage to a DC load, a vibration motor for confirming the arrival of radio waves that is composed of a vibration DC motor that shifts the center of gravity of the weight to generate vibration, and excitation by applying a DC voltage. Buzzer for incoming call, which is composed of magnetic sounding body that operates by the sound effect, potential control means that determines the operating potential when the vibration motor operates, and potential that determines the operating potential when the buzzer operates. A control means, an operation control circuit having a function of sending a switching control signal in accordance with the operation timings of the vibration motor and the buzzer, and managing the operation state of the receiving circuit section, and a signal from the operation control circuit. A first switching circuit for receiving and performing a switching operation for controlling the operation of the vibration motor and the vibration motor potential control means. A second switching circuit that receives a signal from the operation control circuit and performs a switching operation for controlling the operation of the buzzer and the buzzer potential control means; and the vibration level of the vibration motor from the operation control circuit. And an attenuator control means for determining the operating potential of the driving transistor in response to a control signal corresponding to the switching of the sound pressure level of the buzzer and the operation of the receiving circuit section, the vibration motor operation, and the buzzer operation by the operation control circuit. By controlling so that the timings do not overlap, the first switching circuit or the second switching circuit is operated to simultaneously control the operation of the vibration motor and the potential control means for the vibration motor, or the operation of the buzzer. Simultaneously controlling the potential control means for the buzzer, the optimum supply voltage and operation type for the motor and buzzer respectively. The operation of the receiving circuit is stopped during the operation of the motor and buzzer at the same time as the operation of the motor, preventing the power circuit from overloading and malfunctioning due to noise jumping into the receiving circuit caused by the operation of the motor and buzzer. The DC load drive circuit according to claim 1, wherein