Step-up power supply circuit and semiconductor integrated circuit device

• US 6,191,962 B1
• Filed: 12/02/1999
• Issued: 02/20/2001
• Est. Priority Date: 12/22/1998
• Status: Expired due to Fees

• Current Assignee: Pioneer Corporation
• Original Assignee: Pioneer Corporation
• Inventors: Yoshizumi, Norio, Ozawa, Akio, Inohana, Haruyuki
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): Vu, Bao Q.
• Application Number:
  US09/453,472
• Time in Patent Office: 446 Days
• Field of Search: 363/59, 363/60, 307/110
• US Class Current: 363/60
• CPC Class Codes: H02M 1/0045 Converters combining the concepts of switch-mode regulation and linear regulation, e.g. linear pre-regulator to switching converter, linear and switching converter in parallel, same converter or same transistor operating either in linear or switching mode
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps

Abstract

A step-up power supply circuit is provided with a diode D1 to which a predetermined voltage Vcc is applied from a power supply 16, a capacitor C_D1 connected to the diode D1, a diode D2 connected to a joint point between the diode D1 and the capacitor C_D1,and also a capacitor C_D2 connected to the diode D2. A trapezoidal wave signal S_D produced by a triangular wave generating circuit 7, an amplifier 8, and a drive unit 9 is applied to the capacitor C_D1 so as to turn ON/OFF the diodes D1 and D2. As a result, a step-up voltage HVcc approximately two times higher than the voltage Vcc is produced across the capacitor C_D2. Amplifiers AM₀ to AM_n are operated under the step-up voltage HVcc produced from the step-up power supply circuit with employment of this arrangement, and the step-up voltage HVcc is judged by a judging circuit 17. As a result of this judgement, amplification factors of amplifiers AM₀ to AM_n are automatically and variably adjusted.

Claims

1. A step-up power supply circuit comprising:

a first rectifying element and a first capacitive element series-connected between a first contact point and a second contact point;

a second rectifying element connected between a joint point between said first rectifying element and said first capacitive element, and a third contact point;

a second capacitive element connected between said third contact point and a fourth contact point; and

drive means for outputting a signal having a waveform whose amplitude is not rapidly changed, but becomes constant every predetermined time period;

wherein plural sets containing said first/second rectifying elements and said first/second capacitive elements are cascade-connected to each other in a plurality of stages; and

wherein said first contact point of a post-staged set is connected to said third contact point of a pre-staged set;

said second contact point is commonly connected;

a predetermined power supply voltage is applied to said first contact point of a topmost-staged set;

the signal of said drive means is supplied to said second contact point of the topmost-staged set; and

said fourth contact point is set to a lower voltage than said predetermined voltage.

2. A step-up power supply circuit as claimed in claim 1 wherein said signal is a trapezoidal waveform signal.

3. A semiconductor integrated circuit device comprising either one set or plural sets of said first and second rectifying elements as recited in claim 1.

6. The circuit as claimed in claim 1, wherein the fourth contact point is connected to ground.

4. A semiconductor integrated circuit device equipped with a step-up power supply circuit, in which the step-up power supply circuit and a circuit operated by using a step-up voltage produced from said step-up power supply circuit as an operating power supply voltage are formed on the same semiconductor substrate, comprising:

judging means for judging the step-up voltage produced by said step-up power supply circuit; and

adjusting means for adjusting an operating condition of said circuit operated by using the step-up voltage as the operating power supply voltage based upon the judged result of said judging means.

5. A semiconductor integrated circuit device as claimed in claim 4 wherein said circuit operated by using the step-up voltage as the operating power supply voltage is an amplifier;

and said adjusting means adjusts an amplification factor of said circuit.

7. A step-up power supply circuit, comprising:

a first rectifying device and a first capacitive device connected in series between a first node and a second node;

a second rectifying device connected between a third node and a fourth node, wherein said third node is located between said first rectifying device and said first capacitive device;

a second capacitive device connected between said fourth node and a fifth node; and

a waveform generating circuit that outputs a waveform signal, wherein said waveform signal oscillates such that an amplitude of said waveform signal does not rapidly change between oscillations and wherein said amplitude is constant for a predetermined time during a period of said waveform signal,

wherein a constant power supply voltage is supplied to said first node, said waveform signal is supplied to said second node, and a constant ground voltage is supplied to said fifth node.

8. The circuit as claimed in claim 7, wherein said waveform generating circuit comprises:

a wave generating circuit that outputs an oscillating signal having an amplitude less than a clipping voltage;

an amplifier that amplifies said oscillating signal to at least indirectly generate said waveform signal, wherein said amplitude of said waveform signal is clipped at said clipping voltage.

9. The circuit as claimed in claim 8, wherein said waveform signal is a trapezoidal signal.

10. The circuit as claimed in claim 8, wherein said oscillating signal is a triangular wave signal.

11. The circuit as claimed in claim 9, wherein said oscillating signal is a triangular wave signal.

12. The circuit as claimed in claim 8, wherein said oscillating signal is a sine wave signal.

13. The circuit as claimed in claim 7, further comprising:

a third rectifying device and a third capacitive device connected in series between said fourth node and said second node;

a fourth rectifying device connected between a sixth node and a seventh node, wherein said sixth node is located between said third rectifying device and said third capacitive device; and

a fourth capacitive device connected between said seventh node and said fifth node.

19. The circuit as claimed in claim 7, wherein a step-up voltage is generated at said fourth node and is greater than the constant power supply voltage, and

wherein the circuit further comprises:

a judging circuit that that inputs the step-up voltage and produces a judging signal based on a value of the step-up voltage;

an operational circuit that is powered by the step-up voltage; and

an adjustment circuit that inputs the judging signal and adjusts an operation of the operational circuit based on the judging signal.

20. The apparatus as claimed in claim 19, wherein the operational circuit is an amplifier and the adjustment circuit adjusts the gain of the amplifier.

21. The apparatus as claimed in claim 20, wherein the amplifier inputs an input signal and amplifies the input signal to produce an output signal that is supplied to a load.

14. An apparatus, comprising:

a judging circuit that that inputs a step-up voltage generated by a power supply circuit and that produces a judging signal based on a value of the step-up voltage;

an operational circuit that is powered by the step-up voltage; and

an adjustment circuit that inputs the judging signal and adjusts an operation of the operational circuit based on the judging signal.

15. The apparatus as claimed in claim 14, wherein the operational circuit comprises an amplifier and the adjustment circuit adjusts the gain of the amplifier.

16. The apparatus as claimed in claim 15, wherein the amplifier inputs an input signal and amplifies the input signal to produce an output signal that is supplied to a load.

17. The apparatus as claimed in claim 15, wherein the adjustment circuit comprises:

a first switch that inputs the judging signal and that is selectively activated in accordance with the judging signal; and

a first gain adjusting circuit that controls the gain of the amplifier when the first switch is activated.

18. The apparatus as claimed in claim 17, wherein the adjustment circuit further comprises:

a second switch that inputs the judging signal and that is selectively activated in accordance with the judging signal; and

a second gain adjusting circuit that controls the gain of the amplifier when the second switch is activated.