Circuit Diagram of Ultra-High Input Impedance AC Unity Gain Amplifier

This circuit is an ultra high input impedance AC unity gain amplifier and used to get unity gain from ultra high input impedance AC. Here is the schematic :

Ultra-High input impedance AC unity gain amplifier circuit

Ultra-High input impedance AC unity gain amplifier circuit diagram

2N4416 IC is used to reduce the input capacitance. The IC has low capacitance. It’s operated as a source follower with bootstrapped gate bias resistor and the resistor.

Source : National Semiconductor Application Note