CONTROL SIGNAL GENERATING CIRCUIT, CHARGE PUMP DRIVE CIRCUIT, CLOCK DRIVER, AND METHOD OF DRIVING CHARGE PUMP

摘要

There is provided a control signal generating circuit which generates a control signal which can keep down the switching current and reduce the switching noise. A control signal generation circuit which generates a control signal for control of a gate of a PMOS transistor is comprised of a switch which is connected to a constant current source and a gate of the PMOS transistor and which is controlled based on an input signal and a switch which is connected to a constant current source and a gate of the PMOS transistor and which is controlled based on an input signal and a control signal. Further, the voltage value of the control signal is made to change by a slant based on the input signal and the control signal slant is switched so as to become smaller after the voltage value of the control signal exceeds the threshold value of the MOS transistor compared with when the voltage value of the control signal is equals to or less than the threshold value of the MOS transistor.