The circuit provides for accurate half-wave rectification of the incoming signal. For positive signals, the gain is 0; for negative signals, the gain is -1. By reversing both diodes, the polarity can be inverted. This circuit provides an accurate output, but the output impedance differs for the two input polarities and buffering may be needed.
The output must slew through two diode drops when the input polarity reverses. The^NE5535 device will work up to 10 kHz with less than 5% distortion.