Patent ID: 7511563

Claim:
A ripple current reduction circuit, comprising: a supply node adapted to be coupled to the output of a voltage source, said voltage source output having an associated ripple voltage; a first current source arranged to produce a first current I 1 ; a first current mirror referred to said supply node, said first mirror having an input node connected to receive I 1 and arranged to mirror I 1 to a second node, said mirrored current having an associated ripple current induced by said ripple voltage; a second current source arranged to produce a second current I 2 , said second current I 2 being a constant fixed current; a second current mirror referred to said second node, said second mirror having an input node connected to receive I 2 and arranged to mirror I 2 to an output node; and a shunt circuit coupled between said second node and a circuit common point and arranged to continuously shunt a portion of the current provided at said second node to said circuit common point, at least a portion of said shunted current including a ripple component induced by the ripple current present in said voltage source output; such that the current provided at said output node has a ripple current having a magnitude which is less than that present in said mirrored current from said first current mirror.