The invention belongs to the field of analog
integrated circuit calculation, and particularly relates to a
grid voltage bootstrapped switch circuit applied to an
assembly line successive approximation type ADC, the working mode of the
grid voltage bootstrapped switch circuit is divided into a sampling state and a holding state, and the two states are controlled by two non-overlapping clocks CLK and CLKB respectively; when the CLK is in a high level and the CLKB is in a low level, the
grid voltage bootstrapped switch is in a holding state, and the output
voltage VOUT is kept unchanged; on the contrary, when the CLK is in a low level and the CLKB is in a high level, the grid
voltage bootstrapped switch is in a sampling state, and the output
voltage VOUT changes along with the change of the input
signal VIN. According to the circuit, the area of a traditional
gate voltage bootstrapped switch is reduced, meanwhile, the gate
parasitic capacitance of the sampling input tube is effectively reduced, and the
linearity and speed of the
gate voltage bootstrapped switch are improved on the whole.