Control circuit for load switch

The invention provides a control circuit for a load switch, which includes a charge pump circuit, an oscillator, and a current signal generator. The charge pump circuit generates a control signal according to a clock signal. The load switch is turned on or turned off according to the control signal. The oscillator generates the clock signal according to a control current. The current signal generator provides a resistor string to receive a power voltage. The resistor string of the current signal generator generates a sensed current or a sensed voltage according to the power voltage. The current signal generator generates the control current according to a reciprocal of the sensed current or a square of the sensed voltage. A frequency of the clock signal is negatively related to the power voltage. 本发明提供一种负载开关的控制电路，其包括电荷泵电路、振荡器以及电流信号产生器。电荷泵电路依据时脉信号以产生控制信号。负载开关依据控制信号以导通或断开。振荡器依据控制电流以产生时脉信号。电流信号产生器提供一电阻串以接收电源电压。电流信号产生器的电阻串依据电源电压以产生感测电流或感测电压。电流信号产生器并依据感测电流的倒数或感测电压的平方以产生控制电流。其中，时脉信号的频率与电源电压的电压值呈负相关。