Patent ID: 6028473
Filing Date: 2000-02-22
Classification: H02M

Abstract:
A charge pump apparatus, comprising;a first active capacitor activated by a threshold voltage, having a first lead and a second lead;a second capacitor connected in series with the first active capacitor, having a first lead connected to a common node with the second lead of the first active capacitor and a second lead, the second lead connected to a particular node;a pump clock input connected to the first lead of the first active capacitor;a voltage clamp coupled to the particular node which provides a bias point; anda dynamic biasing circuit connected to the common node which provides charge to the second lead of the first active capacitor at the common node and the particular node between transitions of the pump clock to keep the first active capacitor activated during transitions of the pump clock;wherein the second capacitor comprises a second active capacitor which requires a higher voltage on its second lead than on the common node by the threshold to activate, and the bias point is more than a sum of the threshold plus a peak voltage reached by the common node during transitions of the pump clock.