Patent ID: 7616469
Filing Date: 2009-11-10
Classification: G11C

Abstract:
1. A super leakage current cut-off device, applied to a ternary content addressable memory (TCAM), utilizing a super cut-off power gating control circuit to reduce the leakage current through the don't-care cells of said TCAM, wherein said super cut-off power gating control circuit comprises: a first high-end power gating transistor connected between a charging terminal of a first inverter of a don't-care cell in said TCAM and a voltage source; a second high-end power gating transistor connected between a charging terminal of a second inverter of said don't-care cell in said TCAM and said voltage source; a first low-end power gating transistor connected between a discharging terminal of said first inverter of said don't-care cell in said TCAM and the ground; and a second low-end power gating transistor connected between a discharging terminal of said second inverter of said don't-care cell in said TCAM and the ground; wherein the gate electrodes of said first high-end power gating transistor, said second high-end power gating transistor, said first low-end power gating transistor and said second low-end power gating transistor respectively are expressed respectively by a first high-end voltage signal, a second high-end voltage signal, a first low-end voltage signal and a second low-end voltage signal to determine turn on/off said first high-end power gating transistor, said second high-end power gating transistor, said first low-end power gating transistor and said second low-end power gating transistor to reduce the leakage current through said don't-care cells in said TCAM according to a switching control signal.