Patent ID: 7285992
Filing Date: 2007-10-23
Classification: H03F

Abstract:
1. An apparatus that is arranged to drive a load in response to a differential input signal, comprising: a charge-pump circuit that is arranged to generate first and second local power-supply rails carrying a first local power-supply voltage and a second local power-supply voltage, respectively; a pre-driver circuit that is arranged for operation from the first and second local power-supply rails and is configured to provide linear drive signals in response to the differential input signal such that a first one of the linear drive signals ranges to a first voltage that is substantially equivalent to the first local power-supply voltage and a second one of the linear drive signals ranges to a second voltage that is substantially equivalent to the second local power-supply voltage; and a non-inverting linear follower output stage circuit that is arranged for operation from third and fourth power-supply rails carrying a third local power-supply voltage and a fourth local power-supply voltage, respectively, wherein at least one of the third and the fourth local power-supply voltages is distinct from the first and the second local power-supply voltages, the non-inverting linear follower output stage circuit is further arranged to drive the load in response to the linear drive signals such that current is delivered to the load from at least one of the third and fourth power-supply rails, wherein the pre-driver circuit is configured to linearly drive the non-inverting linear follower output stage circuit such that a substantially rail-to-rail signal swing with respect to the third and fourth power-supply rails is achieved at the load with reduced signal distortion, and the non-inverting linear follower output stage circuit comprises: wherein the charge-pump circuit comprises: