New precision rectifier circuits with high accuracy and wide bandwidth

Two new circuits for precise full-wave rectification are presented. The first is based on a current feedback amplifier with a new current-mode absolute-value circuit in its feedback loop. The second utilizes an operational conveyor working in conjunction with a current-mode absolute-value circuit in a new configuration. Both circuits have high accuracy and wide bandwidth, giving undistorted rectified waveforms up to 500 kHz in the first case and 1 MHz in the other. Additionally, both systems have high sensitivity, being able to full-wave rectify signals with amplitudes as small as 5 mV peak at 100 kHz. Finally, the new systems have excellent temperature stability, low offset output voltage and are suitable for IC fabrication.