Patent ID: 7148739

Claim:
A method for operating a charge pump, the method comprising: providing a pulse train into a charge pump stage, wherein said pulse train enables charge transfer through said charge pump stage in a high phase and blocks charge transfer through said charge pump stage in a low phase; driving a bulk of a charge transfer transistor to a drain terminal voltage level of an n-channel metal oxide semiconductor (NMOS) transistor, said source terminal voltage level not greater than the minimum of a source voltage and a drain voltage of said charge transfer transistor in the high phase of said pulse train, wherein the gate of said NMOS transistor is connected to the drain of said charge transfer transistor, and the source of said NMOS transistor is connected to a positive supply voltage; and driving said bulk of said charge transfer transistor to substantially a ground potential level, said ground potential level lower than said drain terminal voltage level and not greater than the minimum of said source voltage and said drain voltage of said charge transfer transistor in the low phase of said pulse train.