RIPPLE CURRENT REDUCTION CIRCUIT

摘要

A ripple current reduction circuit includes a supply node (10) coupled to the output of a high ripple voltage source such as a charge pump (14). A first current mirror (16) is referred to the supply node and mirrors a current (I1) to a second node (20), the mirrored current (I3) including a ripple current induced by the ripple voltage. A second current mirror (22) is referred to the second node and mirrors a current (12) to an output node, which provides a current (I_LOAD) to a load (32). The mirrors are sized such that the current provided at the second node is greater than the current required by the second mirror to provide (I_LOAD). The excess current, at least a portion of which includes a ripple component induced by the ripple voltage, is shunted to ground. As such, the magnitude of the ripple component in (I_LOAD) is less than that present in (I3).