JP5710405B2 - Booster - Google Patents

Description

  The present invention relates to a boosting device including a charge pump unit that generates a boosted voltage.

  As this type of booster, a charge pump circuit disclosed in the following Patent Document 1 is known. In the charge pump circuit, in a configuration for generating a positive voltage, a plurality of diodes connected in series in multiple stages by connecting a cathode terminal of a diode in the previous stage to an anode terminal of a diode in the subsequent stage, and an anode terminal of each diode Based on a capacitor (capacitance) having one end connected to the cathode, a load capacitance connected to the cathode terminal of the last-stage diode, and a pulse signal output from the oscillator, a pair of complementary first clock signal and second And an inverter circuit for generating a clock signal.

  In this charge pump circuit, the first clock signal output from the inverter circuit is supplied to the other end of each capacitor connected to the anode terminal of each odd-numbered diode, and is output alternately with the first clock signal. A 2-clock signal is supplied to the other end of each capacitor connected to the anode terminal of each even-numbered diode, thereby boosting the DC voltage supplied to the anode terminal of the frontmost diode and charging the load capacitance. In addition, this boosted voltage can be output to the outside.

JP 2002-208290 A (page 3, FIG. 16)

  However, the above charge pump circuit has the following problems to be solved. That is, in this charge pump circuit, it is necessary to prepare an oscillator separately. That is, since the oscillator is separate from the charge pump circuit, the oscillator is turned on / off in conjunction with the on / off of the charge pump circuit. I can't let you. For this reason, this charge pump circuit has a problem to be solved that the power utilization efficiency of the entire circuit including the oscillator is reduced because the oscillator is always on regardless of whether the charge pump circuit is on or off. Existing.

  The present invention has been made to solve such a problem, and a main object of the present invention is to provide a booster device including a charge pump unit that can improve power use efficiency.

  In order to achieve the above object, a booster according to claim 1 includes a charge pump unit that generates a boosted voltage, and a relaxation oscillation unit that oscillates a pulse signal for causing the charge pump unit to perform a boost operation in an oscillation operation state. And the relaxation type oscillation unit is connected between a Schmitt trigger inverter, an input terminal of the Schmitt trigger inverter, and a reference voltage. The oscillation capacitor, the feedback resistor unit composed of at least two resistors connected in series and connected between the input terminal and the output terminal of the Schmitt trigger inverter, and the 2 when the control signal is inputted. A control circuit that controls the voltage of the connection point of the resistors to control the oscillation of the pulse signal by the relaxation oscillation unit in a stopped state;

  According to a second aspect of the present invention, in the booster device according to the first aspect, the control circuit includes a diode.

  According to a third aspect of the present invention, in the step-up device according to the first or second aspect, when the control signal is input, the step-up device shifts from an off state to an on state and discharges the charge of the step-up capacitor. A discharge part is provided.

  According to the booster device of the first aspect, the voltage at the connection point of the two resistors constituting the feedback resistance unit of the relaxation type oscillation unit is controlled by the control circuit to stop the oscillation of the pulse signal by the relaxation type oscillation unit. Since it can be controlled, the output of the boosted voltage by the charge pump unit can be automatically stopped by stopping the self-oscillation operation of the relaxation type oscillation unit. For this reason, according to this boosting device, it is possible to avoid a situation in which the relaxation type oscillation unit is maintained in the operating state in the state where the output of the boosted voltage is stopped (the state where the boosting operation is stopped). Therefore, it is possible to improve the power utilization efficiency of the booster as a whole.

  Further, according to the booster device of the second aspect, the control circuit can be configured simply.

  According to the boosting device of claim 3, when the control signal is input, the discharging unit discharges the charge of the boosting capacitor in accordance with the stop of the boosting operation by the charge pump unit. The boosted voltage output from can be rapidly shifted to, for example, the ground voltage in the circuit.

1 is a circuit diagram of a booster device 1. FIG. It is a circuit diagram of booster 1A. It is a principal part circuit diagram of booster 1 (1A) which shows other composition of a drive element.

  Hereinafter, embodiments of a booster device including a charge pump unit will be described with reference to the accompanying drawings.

  First, the configuration of the booster 1 that outputs the positive boosted voltage Vout will be described with reference to the drawings.

  As shown in FIG. 1, the booster 1 includes a relaxation oscillation unit 2, a charge pump unit 3, and a discharge unit 4, and is configured as a charge pump type booster.

  The relaxation oscillation unit 2 includes a Schmitt trigger inverter 11, an oscillation capacitor 12, a feedback resistor unit 13, and a control circuit 14. The Schmitt trigger inverter 11 operates by receiving the supply of the power supply voltage Vdd.

  The oscillation capacitor 12 is connected between the input terminal of the Schmitt trigger inverter 11 and a reference voltage (power supply voltage Vdd or in-circuit ground G. In this example, in-circuit ground G). The feedback resistor unit 13 includes at least two resistors (in this example, two resistors 13a and 13b as an example) connected in series. Further, the feedback resistor unit 13 is connected between the input terminal and the output terminal of the Schmitt trigger inverter 11. The control circuit 14 includes a diode (hereinafter also referred to as “control diode 14”). The control diode 14 has a cathode terminal connected to a connection point A of the resistors 13 a and 13 b constituting the feedback resistor unit 13. As a result, the control circuit (control diode) 14 is supplied with (inputted to) the control voltage Vc (voltage having substantially the same voltage value as the power supply voltage Vdd) as a control signal to the anode terminal. Is controlled to be substantially the same voltage as the power supply voltage Vdd.

  With this configuration, the relaxation oscillation unit 2 is substantially the same voltage as the power supply voltage Vdd of the voltage at the connection point A by the control diode 14 when the control voltage Vc is not supplied (input) to the anode terminal of the control diode 14. Since the control is not performed, the two threshold voltages for the input voltage defined in advance in the Schmitt trigger inverter 11, the resistance value of the feedback resistor section 13 (the series resistance value of the resistors 13a and 13b), and the oscillation voltage A pulse signal S0 having a duty ratio and a frequency determined by the capacitance value of the capacitor 12 is generated and output. On the other hand, when the control voltage Vc as a control signal is supplied (input) to the anode terminal of the control diode 14, the control diode 14 forcibly causes the voltage at the connection point A to be a constant voltage close to the power supply voltage Vdd. Therefore, the relaxation oscillation unit 2 is controlled to stop the oscillation of the pulse signal S0.

  The charge pump unit 3 includes a plurality of (in this example, four as an example) boosting diodes 21a, 21b, 21c, and 21d (hereinafter also referred to as “boosting diode 21” unless otherwise specified), and a plurality of (in this example, boosting diode 21). , Four as an example) boost capacitors 22a, 22b, 22c, 22d (hereinafter also referred to as “boost capacitor 22” unless otherwise specified), and a plurality (three in this example as an example) of inverters 23a, 23b. , 23c (hereinafter also referred to as "inverter 23" unless otherwise specified), a voltage regulating diode 24 and a smoothing capacitor 25 are provided.

  The boosting diodes 21a, 21b, 21c, and 21d are connected in series (in the example, four stages as an example) in a forward connection state (a state in which the cathode terminal in the previous stage is connected to the anode terminal in the subsequent stage). Yes. The step-up capacitor 22 is arranged with one end connected to the anode terminal of the step-up diode 21 for each step-up diode 21. Specifically, one end of boost capacitor 22a is connected to the anode terminal of boost diode 21a, one end of boost capacitor 22b is connected to the anode terminal of boost diode 21b, and boost capacitor 22c One end is connected to the anode terminal of the boosting diode 21c, and one end of the boosting capacitor 22d is connected to the anode terminal of the boosting diode 21d.

  In this example, the inverters 23a, 23b, and 23c are connected in series in multiple stages (in this example, three stages) and operate by receiving the supply of the power supply voltage Vdd. The inverters 23 a, 23 b, and 23 c function as drive elements that drive the boost capacitors 22 together with the Schmitt trigger inverter 11 of the relaxation oscillation unit 2.

  Specifically, the Schmitt trigger inverter 11 has its output terminal connected to the other end of the first-stage boost capacitor 22a and the input terminal of the inverter 23a, and functions as a first-stage drive element. That is, the Schmitt trigger inverter 11 synchronizes the voltage at the other end of the boosting capacitor 22a and the voltage at the input terminal of the inverter 23a with the power supply voltage Vdd and the voltage of the in-circuit ground G in synchronization with the timing of the output pulse signal S0. It is prescribed alternately.

  The front-stage inverter 23a has its output terminal connected to the other end of the second-stage boost capacitor 22b and the input terminal of the inverter 23b, and functions as a second-stage drive element. That is, the inverter 23a synchronizes the voltage of the other end of the boosting capacitor 22b and the voltage of the input terminal of the inverter 23b with the power supply voltage Vdd and the in-circuit ground G in synchronization with the timing of the signal whose phase is inverted with the pulse signal S0. It is prescribed alternately with voltage.

  The output terminal of the next-stage inverter 23b is connected to the other end of the third-stage boost capacitor 22c and the input terminal of the inverter 23c, and functions as a third-stage drive element. That is, the inverter 23b alternately defines the voltage at the other end of the boosting capacitor 22c and the voltage at the input terminal of the inverter 23c as the power supply voltage Vdd and the voltage of the in-circuit ground G in synchronization with the timing of the pulse signal S0. To do.

  The output terminal of the last-stage inverter 23c is connected to the other end of the fourth-stage boosting capacitor 22d and functions as a fourth-stage driving element. That is, the inverter 23c alternately regulates the voltage at the other end of the boosting capacitor 22d to the power supply voltage Vdd and the voltage of the in-circuit ground G in synchronization with the timing of the signal whose phase is inverted with respect to the pulse signal S0.

  With this configuration, the other ends of the odd-numbered capacitors 22a and 22c are alternately switched to the power supply voltage Vdd and the voltage of the in-circuit ground G in synchronization with the timing of the pulse signal S0 by the Schmitt trigger inverter 11 and the inverter 23b. It is prescribed. On the other hand, the other ends of the even-numbered capacitors 22b and 22d are alternately regulated by the inverters 23a and 23c to a voltage opposite to that of the odd-numbered capacitors 22a and 22c. That is, the other ends of the even-numbered capacitors 22b and 22d are defined as the voltage of the in-circuit ground G when the other ends of the odd-numbered capacitors 22a and 22c are defined as the power supply voltage Vdd. When the other ends of the capacitors 22a and 22c are regulated to the voltage of the in-circuit ground G, they are regulated to the power supply voltage Vdd. That is, the inverter 23 as each drive element is synchronized with the timing of the pulse signal S0 (according to the “power supply voltage Vdd” and “in-circuit ground G” of the pulse signal S0), and the other end of the corresponding capacitor 22 is connected. The voltage is defined as one of the power supply voltage Vdd and the in-circuit ground G.

  The voltage regulating diode 24 is connected between the power supply voltage Vdd and the anode terminal of the boosting diode 21a, and regulates the voltage of the anode terminal of the boosting diode 21a to the power supply voltage Vdd. The smoothing capacitor 25 is connected between the cathode terminal (the output terminal of the charge pump unit 3) of the boosting diode 21d at the last stage and the in-circuit ground G.

  The discharge part 4 includes a discharge resistor 4a and a switch element (field effect transistor or bipolar transistor) 4b connected in series with each other. The discharge unit 4 is connected between the cathode terminal of the boosting diode 21d (the output terminal of the charge pump unit 3) and the in-circuit ground G (that is, connected in parallel to the smoothing capacitor 25). ). The switch element 4b is so-called high active, and shifts to an on state when the control voltage Vc is supplied (input), and shifts to an off state when the supply (input) of the control voltage Vc is stopped. To do.

  Next, the operation of the booster 1 will be described with reference to the drawings.

  First, when the control voltage Vc is not supplied, the control diode 14 has a high impedance on the cathode terminal side connected to the connection point A. Moreover, in the discharge part 4, the switch element 4b transfers to an OFF state.

  For this reason, in the relaxation type oscillation unit 2, the voltage at the connection point A of the two resistors 13 a and 13 b can be changed according to the output voltage of the Schmitt trigger inverter 11. Therefore, the relaxation oscillation unit 2 executes a self-excited oscillation operation and continuously outputs the pulse signal S0 to the charge pump unit 3.

  Thereby, in the charge pump unit 3, as described above, the other end of each boosting capacitor 22 is driven by each inverter 23, whereby the voltage at the other end of the odd-numbered capacitors 22a and 22c becomes a pulse signal. In synchronization with the timing of S0, the power supply voltage Vdd and the voltage of the in-circuit ground G are alternately defined. On the other hand, the voltages at the other ends of the even-numbered capacitors 22b and 22d are the odd-numbered capacitors 22a and 22c. Are alternately defined as a voltage opposite to the voltage at the other end.

  Therefore, when the charge pump unit 3 executes the boosting operation and the voltage drop at each boosting diode 21 and the voltage regulating diode 24 is almost zero, each boosting capacitor 22a, 22b, 22c, 22d. Are charged to voltages of Vdd, Vdd × 2, Vdd × 3, and Vdd × 4. For this reason, the smoothing capacitor 25 connected to the cathode terminal of the boosting diode 21d at the last stage is charged with the boosted voltage (Vdd × 4) of the power supply voltage Vdd, and the boosted voltage (Vdd × 4). Smooth 4). Thereby, the booster 1 outputs the voltage (Vdd × 4) as the positive boosted voltage Vout.

  Next, the operation of the booster 1 when the control voltage Vc is supplied (input) to the control diode 14 and the switch element 4b in the output state of the boost voltage Vout will be described.

  In the relaxation type oscillating unit 2, a voltage substantially the same as the power supply voltage Vdd is supplied to the connection point A through the control diode 14, and therefore, the input terminal of the Schmitt trigger inverter 11 is held at a voltage substantially the same as the power supply voltage Vdd. . As a result, the relaxation oscillation unit 2 stops the self-excited oscillation operation. Further, since the relaxation oscillation unit 2 stops the self-excited oscillation operation, the output of the pulse signal S0 from the relaxation oscillation unit 2 is stopped. As a result, the charge pump unit 3 also stops the boosting operation. Therefore, the relaxation oscillation unit 2 and the charge pump unit 3 both stop operating.

  Moreover, in the discharge part 4, the switch element 4b shifts to an ON state by supplying the control voltage Vc to the switch element 4b. As a result, the discharging unit 4 performs a discharging operation in accordance with the stop of the boosting operation in the charge pump unit 3, and discharges the charges charged in the smoothing capacitor 25 and each boosting capacitor 22. Therefore, the boosted voltage Vout is rapidly lowered to the voltage of the in-circuit ground G.

  On the other hand, when the supply of the control voltage Vc is stopped again, the output of the pulse signal S0 by the relaxation oscillation unit 2 is started, and the charge pump unit 3 starts the boosting operation. At the same time, the switching element 4b shifts to the off state, so that the discharging operation by the discharging unit 4 is stopped. Therefore, the booster 1 restarts the output of the positive boost voltage Vout.

  Next, the configuration of the booster 1A that outputs the negative boost voltage Vout will be described with reference to the drawings. In addition, about the structure same as the pressure | voltage rise apparatus 1, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

  As shown in FIG. 2, the booster 1 </ b> A includes a relaxation oscillation unit 2, a charge pump unit 3 </ b> A, and a discharge unit 4. In this case, only the configuration of the charge pump unit 3A is different from the booster 1 described above, and the configurations of the relaxation oscillation unit 2 and the discharge unit 4 are the same. Hereinafter, the configuration of the charge pump unit 3A different from the booster 1 will be described.

  The charge pump unit 3A includes a plurality of (in this example, four as an example) boosting diodes 21a, 21b, 21c, and 21d, and a plurality of (in this example as four as an example) boosting capacitors 22a, 22b, 22c, 22d, a plurality of (in this example, three as an example) inverters 23a, 23b, 23c, a voltage regulating diode 24, and a smoothing capacitor 25.

  The boosting diodes 21a, 21b, 21c, and 21d are connected in series (in this example, four stages as an example) in a forward connection state (a state in which the anode terminal in the previous stage is connected to the cathode terminal in the subsequent stage). Yes. The step-up capacitor 22 is arranged with one end connected to the cathode terminal of the step-up diode 21 for each step-up diode 21. Specifically, one end of boost capacitor 22a is connected to the cathode terminal of boost diode 21a, one end of boost capacitor 22b is connected to the cathode terminal of boost diode 21b, and boost capacitor 22c One end is connected to the cathode terminal of the boosting diode 21c, and one end of the boosting capacitor 22d is connected to the cathode terminal of the boosting diode 21d.

  Note that the Schmitt trigger inverter 11 of the relaxation oscillator 2 that functions as the first-stage driving element for the boosting capacitor 22 has its output terminal connected to the other end of the first-stage boosting capacitor 22a and the input terminal of the inverter 23a. It is connected. The output terminal of the inverter 23a functioning as the second stage driving element is connected to the other end of the second stage boosting capacitor 22b and the input terminal of the inverter 23b. The inverter 23b functioning as a third stage drive element has an output terminal connected to the other end of the third stage boost capacitor 22c and an input terminal of the inverter 23c, and functions as a fourth stage drive element. The output terminal 23c is connected to the other end of the fourth boost capacitor 22d.

  With this configuration, in the charge pump unit 3A as well as in the charge pump unit 3, the other ends of the even-numbered capacitors 22b and 22d are connected to the odd-numbered capacitors 22a and 22c in synchronization with the pulse signal S0. When the other end is defined as the power supply voltage Vdd, it is defined as the voltage of the in-circuit ground G. When the other end of the odd-numbered capacitors 22a and 22c is defined as the voltage of the circuit ground G, the power supply voltage Vdd.

  The voltage regulating diode 24 is connected between the in-circuit ground G and the cathode terminal of the boosting diode 21a, and regulates the voltage of the cathode terminal of the boosting diode 21a to the voltage of the in-circuit ground G. The smoothing capacitor 25 is connected between the anode terminal (the output terminal of the charge pump unit 3A) of the last boosting diode 21d and the in-circuit ground G.

  Next, the operation of the booster 1A will be described with reference to the drawings.

  First, when the control voltage Vc is not supplied, also in the booster 1A, as in the booster 1, the relaxation oscillation unit 2 performs a self-oscillation operation and continuously applies the pulse signal S0 to the charge pump. Output to part 3A. Moreover, in the discharge part 4, the switch element 4b transfers to an OFF state, and stops discharge operation.

  Accordingly, in the charge pump unit 3A, the other end of each boosting capacitor 22 is driven by each inverter 23, so that the voltage at the other end of the odd-numbered capacitors 22a and 22c is synchronized with the timing of the pulse signal S0. Then, the power supply voltage Vdd and the voltage of the in-circuit ground G are alternately defined. On the other hand, the voltage at the other end of the even-numbered capacitors 22b and 22d is the voltage at the other end of the odd-numbered capacitors 22a and 22c. It is alternately specified to the reverse voltage.

  In this state, when the other end of the boosting capacitor 22a is regulated to the power supply voltage Vdd by the Schmitt trigger inverter 11, one end of the first boosting capacitor 22a is connected to the in-circuit ground G via the voltage regulating diode 24. Since the voltage is regulated, the boosting capacitor 22a is charged to the power supply voltage Vdd.

  Next, when the other end of the boosting capacitor 22a is defined as the voltage of the in-circuit ground G by the Schmitt trigger inverter 11, the other end of the second boosting capacitor 22b is defined as the power supply voltage Vdd by the inverter 23a. . As a result, the voltage at one end of the boosting capacitor 22a becomes −Vdd. For this reason, since the voltage at one end of the boosting capacitor 22b becomes −Vdd via the boosting diode 21a and the voltage at the other end is regulated by the power supply voltage Vdd as described above, Is charged with a voltage of −Vdd × 2 where one end side is a negative voltage with respect to the other end side.

  Similarly, the third-stage boost capacitor 22c is charged with a voltage of −Vdd × 3, one end of which is a negative voltage with respect to the other end. The fourth-stage boost capacitor 22d has the other end A voltage of −Vdd × 4 in which one end side becomes a negative voltage with respect to the side is charged. Thereby, a negative voltage of −Vdd × 4 is output as the negative boosted voltage Vout from the charge pump unit 3A.

  Next, the operation of the booster 1 when the control voltage Vc is supplied (input) to the control diode 14 and the switch element 4b in the output state of the boost voltage Vout will be described.

  The relaxation oscillation unit 2 stops the self-excited oscillation operation (stops the output of the pulse signal S0) because the voltage almost the same as the power supply voltage Vdd is supplied to the connection point A through the control diode 14. Further, since the relaxation oscillation unit 2 stops the self-excited oscillation operation, the output of the pulse signal S0 from the relaxation oscillation unit 2 is stopped. As a result, the charge pump unit 3A also stops the boosting operation. Therefore, the relaxation oscillation unit 2 and the charge pump unit 3A both stop operating.

  Moreover, in the discharge part 4, the switch element 4b shifts to an ON state by supplying the control voltage Vc to the switch element 4b. For this reason, the discharging unit 4 performs a discharging operation to discharge the electric charges charged in the smoothing capacitor 25 and each boosting capacitor 22. Therefore, the boosted voltage Vout is rapidly raised to the voltage of the in-circuit ground G.

  On the other hand, when the supply of the control voltage Vc is stopped again, the output of the pulse signal S0 by the relaxation oscillation unit 2 is started, and the charge pump unit 3A starts the boosting operation. At the same time, the switching element 4b shifts to the off state, so that the discharging operation by the discharging unit 4 is stopped. Therefore, the booster 1A resumes the output of the negative boost voltage Vout.

  As described above, according to the booster devices 1 and 1A, the voltage at the connection point A between the two resistors 13a and 13b constituting the feedback resistor unit 13 of the relaxation oscillation unit 2 is controlled by the control circuit 14. Thus, by supplying the control voltage Vc and stopping the self-excited oscillation operation of the relaxation oscillation unit 2, the output of the boosted voltage Vout by the charge pump units 3 and 3A can be automatically stopped. Therefore, according to the boosting devices 1 and 1A, the relaxation oscillation unit 2 is maintained in the operating state in a state where the output of the boosted voltage Vout is stopped (a state where the boosting operation is stopped). Since this can be avoided, it is possible to improve the power utilization efficiency of the booster 1, 1A as a whole.

  Further, according to the boosting devices 1 and 1A, since the control circuit 14 is configured by including the diode (control diode 14), the control circuit 14 can be configured simply.

  Further, according to the boosting devices 1 and 1A, the discharge unit 4 that shifts from the off state to the on state when the control voltage Vc is input and discharges the charges of the boosting capacitor 22 and the smoothing capacitor 25 is provided. As a result, the discharge unit 4 discharges the charges charged in the capacitors 22 and 25 of the charge pump units 3 and 3A in accordance with the stop of the boost operation by the charge pump units 3 and 3A. The output boosted voltage Vout can be rapidly shifted to the voltage of the in-circuit ground G.

  In the above boosting device 1, 1A, the Schmitt trigger inverter 11, the inverter 23a, the inverter 23b, and the inverter 23c as drive elements are connected to each of the boosting capacitors 22a, 22b, 22c, and 22d and driven individually. However, when the drive capability of one drive element is sufficient, it is possible to adopt a configuration in which a plurality of boost capacitors are driven by one drive element. For example, as shown in FIG. 3, in the charge pump unit 3 (3A) of the booster 1 (1A), two boost capacitors 22a and 22c are driven by the Schmitt trigger inverter 11, and two boost capacitors are driven by the inverter 23a. A configuration for driving 22b and 22d can be employed.

  In the above boosting device 1, 1 </ b> A, the control circuit 14 for inputting the control voltage Vc as the control signal to the connection point A of the relaxation type oscillation unit 2 is configured using the control diode 14. Although not shown, it can be configured using various switching elements such as transistors instead of diodes. Further, the above boosting devices 1 and 1A employ a configuration in which a voltage having a voltage value almost the same as the power supply voltage Vdd is supplied (input) to the connection point A of the relaxation oscillation unit 2 as the control voltage Vc. In the relaxation oscillation unit 2, by adopting a configuration in which the oscillation capacitor 12 is connected between the input terminal of the Schmitt trigger inverter 11 and the power supply voltage Vdd as the reference voltage, the voltage of the in-circuit ground G is controlled as the control voltage. It is possible to supply (input) Vc to the connection point A so as to stop the oscillation operation of the relaxation oscillation unit 2.

  In this case, the control diode 14 constituting the control circuit 14 has an anode terminal connected to the connection point A and a control voltage Vc input to the cathode terminal. Further, the switch element 4b of the discharge unit 4 is configured to be so-called low active, and is turned on when the control voltage Vc is the voltage of the in-circuit ground G, and is turned off when the control voltage Vc is the power supply voltage Vdd. Configure to transition to the state.

  In addition, the charge pump unit is not limited to the configuration of the charge pump units 3 and 3A described above, and may be configured by using various known circuits.

DESCRIPTION OF SYMBOLS 1,1A Booster 2 Relaxation type oscillation part 3, 3A Charge pump part 4 Discharge part 11 Schmitt trigger inverter 12 Oscillator capacitor 13 Feedback resistor part 14 Control diode (control circuit)
13a, 13b Resistance 21 Boosting diode 21
22 Capacitor for boosting 23 Inverter Vc Control voltage Vout Boosting voltage

Claims (3)

A charge pump unit for generating a boosted voltage;
A relaxation type oscillation unit that oscillates a pulse signal for causing the charge pump unit to perform a boost operation in an oscillation operation state, and configured to output the generated boost voltage;
The relaxation oscillation unit includes a Schmitt trigger inverter, an oscillation capacitor connected between an input terminal of the Schmitt trigger inverter and a reference voltage, and at least two resistors connected in series. The feedback resistor connected between the input terminal and the output terminal, and the oscillation of the pulse signal by the relaxation oscillator by controlling the voltage at the connection point of the two resistors when a control signal is input A booster having a control circuit for controlling the motor to a stop state.   The booster according to claim 1, wherein the control circuit includes a diode.   3. The booster according to claim 1, further comprising: a discharge unit that shifts from an off state to an on state when the control signal is input, and discharges the charge of the boost capacitor.

Images