Matt circuit

A TMOS power FET , Q1 , and LM393 comparator provide a high efficiency rectifier circuit. When Va exceeds Vb1 U1's output becomes high and Q1 conducts. Conversely, when Vb exceeds Va1, the comparator output becomes low and Q1 does not conduct. The Forward drop is determined by Q1's on resistance and current I. The MTH40N05 has an ON resistance of 0.028 Ω ; for I = 10 A , the forward drop is less than 0.3V .Typically , the best Schottky diodes do not even begin conducting below a few hundred mV.

The circuit provides accurate full wave rectification. The output impedance is low for both input polarities, and the errors are small at all signal levels. Note that the output will not sink heavy current, except a small amount through the 10K resistors. Therefore, the load applied should be referenced to ground or a negative voltage. Reversal of all diode polarities will reverse the polarity of the output Since the outputs of the amplifiers must slew through two diode drops when the input polarity changes, 741 type devices give 5% distortion at about 300 Hz. Precision full wave Rectifier Circuit Diagram Sourced By: http://circuitsstream.blogspot.com/2013/07/precision-full-wave-rectifier-circuit.html