Low Forward-Drop Power Supply Circuit

Check out the signal output... this power supply will cut off the negative amplitudo and pass the positive AC signal.

A TMOS power FET , Q1 , and LM393 comparator supply a higher performance rectifier circuit. When V_Aexceeds V_B, U1's output turns into higher and Q1 conducts. Conversely, when V_B exceeds V_A, the comparator output gets low and Q1 does not conduct.

The forward drop is determined by Q1's on resistance and latest I. The MTH40N05 has an on resistance of 0.028 Ohm; for I = 10 A, the forward drop is much less than 0.3 V. Typically, the very best Schottky diodes usually do not even start conducting below several hundred mV.

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Power Supply Adapter

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