Patent ID: 7583133

Claim:
Charge pump circuitry comprising: (a) a current mode charge pump circuit including first and second flying capacitors and various associated switches operative in response to first and second phase signals which are of opposite phase, first and second controlled current sources, and a feedback amplifier all coupled so as to generate a boosted output voltage; (b) self-oscillating circuitry including (1) a comparison circuit having first and second inputs and an output, (2) a flip-flop circuit having a clock input coupled to the output of the comparison circuit and first and second outputs producing the first and second phase signals, respectively, (3) the current mode charge pump circuit producing a discharge signal representative of first and second bottom plate voltages alternately produced on the first and second flying capacitors, and (4) the comparison circuit output indicating times at which the first and second bottom plate voltages approach to within a predetermined voltage of a first supply voltage of the charge pump circuitry, the first input of the comparison circuit being coupled to receive the discharge signal.