A sample hold circuit includes at least one capacitor CS and at least one complementary metal-oxide semiconductor (CMOS) switch. The CMOS switch includes an N-channel metal-oxide semiconductor (NMOS) transistor and a P-channel metal-oxide semiconductor (PMOS) transistor connected in parallel. A high level of a gate signal VGN of the NMOS transistor is adjusted to a voltage level VREG lower than a power supply voltage VDD of a chip on which the CMOS switch is integrated.