AMPLIFIER SYSTEM WITH ON-DEMAND POWER SUPPLY BOOST

摘要

An amplifier system with on-demand power supply boost includes an amplifier circuit (26) for receiving an input signal and a charge pump (12) connected to positive and negative power supplies (Vcc, Vref) and having predetermined supply voltages and being responsive to the input signal for increasing beyond the predetermined supply voltages the supply voltage applied to the amplifier in response to an increase in the input signal and a tracking charge pump usable in the amplifier system which includes a charge storage device (20, 24); a unidirectional isolation device (18, 22) interconnecting the charge storage device and one pole of a power supply; a driver circuit (60) responsive to an input signal and interconnected between both poles of the power supply; the power supply having predetermined power supply voltages; and a bias circuit (28) for biasing the driver circuit to charge the charge storage device in the charge mode and in the boost mode, for increasing beyond the predetermined power supply voltages, the supply voltage supplied by the storage device to an external load in response to an increase in the input signal.