Charge pump with high output current

DETAILED DESCRIPTION In accordance with the present invention, a charge pump circuit is provided that enables the conversion of a low voltage to a higher voltage while delivering a substantial amount of current.
The charge pump circuit includes a plurality of diode-capacitor voltage multiplier pump units connected in parallel with respect to each other.
The plurality of pump units are switched at different times during the pump frequency to minimize noise generation.
In one embodiment of the invention, the charge pump circuit is capable of delivering 8 mA of current.
These and other advantages are achieved with the present invention, in accordance with which a charge pump circuit comprises a first voltage pump unit including at least a first capacitor coupled to a voltage output line that is charged in response to a first clocking signal, and a second voltage pump unit including at least a second capacitor coupled to the voltage output line that is charged in response to a second clocking signal having an unequal phase relative to the first clocking signal.
In accordance with a second aspect of the invention, a charge pump circuit comprises a ring oscillator circuit for providing a plurality of clocking signals, each having an unequal phase with respect to the other.
The charge pump circuit further comprises a plurality of clock control units, each coupled to receive a separate clocking signal from the ring oscillator circuit.
A plurality of voltage pump units are each coupled to a separate clock control unit.
The invention will be more readily understood with reference to the drawings and the detailed description.
As will be appreciated by one skilled in the art, the invention is applicable to charge pump circuits in general and is not limited to the specific embodiment disclosed.