Patent ID: 7577052

Claim:
A power control circuit for an integrated circuit module comprising: at least one switch device coupled between a supply voltage and a power node of the integrated circuit module, wherein the switch device includes a first PMOS device having a source coupled to the supply voltage and a drain coupled to the power node; and a switch control module having a first terminal coupled to the switch device, a second terminal coupled to a control signal, a third terminal coupled to a first storage node of at least one tracking cell, a fourth terminal coupled to a second storage node of the tracking cell, and a fifth terminal coupled to the power node of the integrated circuit module, for controlling the switch device to pass the supply voltage to the power node with or without a substantial voltage drop depending on an operation mode of the integrated circuit module, wherein the switch control module includes a first NMOS device coupled between the first storage node of the tracking cell and a complementary supply voltage, having a gate controlled by the control signal, and a second NMOS device coupled between the gate of the first PMOS device and the complementary supply voltage, having a gate controlled by the second storage node of the tracking cell, and wherein the switch control module provides a discharge path for lowering the voltage at the power node based on the control signal until a predetermined value is written into the tracking cell.