US 6,191,962 B1 · Step-up power supply circuit and semiconductor integrated circuit device

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 CD1 connected to the diode D1, a diode D2 connected to a joint point between the diode D1 and the capacitor CD1,and also a capacitor CD2 connected to the diode D2. A trapezoidal wave signal SD produced by a triangular wave generating circuit 7, an amplifier 8, and a drive unit 9 is applied to the capacitor CD1 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 CD2. Amplifiers AM0 to AMn 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 AMn are automatically and variably adjusted.

Claims21

Dependent claims

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.

9 more elements

Dependencies are inferred from the claim text.

Step-up power supply circuit and semiconductor integrated circuit device

Life of this patent

Step-up power supply circuit and semiconductor integrated circuit device

Life of this patent

Abstract

Claims21