This circuit is a voltage doubler that converts an AC signal into a higher DC voltage.
An AC input (±10V) is fed into two diodes and two capacitors. During each half-cycle of the AC waveform, one diode conducts and charges a capacitor. On the next half-cycle, the second diode conducts and the voltages from both capacitors effectively stack together, producing an output that is approximately double the peak input voltage.
The large capacitors (1 mF) store charge and smooth the output, while the 100kΩ resistor represents the load. Because of diode voltage drops and slight discharge under load, the output is slightly less than ideal, resulting in about 18.3V DC with minimal ripple.
