Sample-and-hold circuit including operational amplifier as an input circuit

摘要

An operational amplifier charges a charge storage capacitor in response to an input signal supplied to a non-inverting input terminal. When a switching signal is low, NPN transistors disposed in an output open circuit are on. Therefore, output transistors disposed in a push-pull circuit are off and the output signal is cut off. Further, in this situation, the potential of a phase compensation capacitor is held because AC coupling of the phase compensation capacitor does not occur.