Double gate transistor for low power circuits

摘要

A double gate MOSFET having a control gate and a signal gate. The effective threshold voltage seen by the signal gate may be modified by charging the control gate. The effective threshold voltage may be increased in magnitude to reduce sub-threshold leakage current when the double gate MOSFET is inactive. When inactive, the control gate is maintained at a negative voltage for a double gate nMOSFET, and is maintained at a positive voltage for a double gate pMOSFET. When active, the control gate is charged to a voltage close to the threshold voltage, and then floated, so that a signal voltage applied to the signal gate may turn the double gate MOSFET ON during a signal voltage transition via the coupling capacitance between the signal and control gates.