Patent ID: 8775854

Claim:
A system comprising: a voltage sensing module configured to sense a supply voltage of a circuit block, generate a first control signal when the supply voltage is less than or equal to a first voltage, and generate a second control signal when the supply voltage is within a predetermined range of a second voltage; and a frequency adjustment module configured to set a frequency of a clock signal supplied to the circuit block to less than a normal operating frequency of the circuit block, wherein the frequency is greater than zero, when (i) the supply voltage is initially supplied to the circuit block after a power on reset operation, and (ii) either the first control signal is received or the second control signal is received, and set the frequency of the clock signal supplied to the circuit block to the normal operating frequency when (i) a predetermined time has elapsed after the first control signal or the second control signal is received, and (ii) the second control signal is received.