# Voltage across diode help

## Main Question or Discussion Point

two ideal diodes are are connected in parallel. this combination is connected across an ac source. the diodes r such that if one of them is forward biased other is reverse biased.
now in the positive half cycle let us take that 1st diode if forward biased and the second reverse biased. if the output voltage is taken across the parallel combination of the diodes what will be its value?is it 0V as one of the diode is forward biased or is it input voltage as the applied voltage is dropped across a reverse biased diode

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You didn't mention if the ac source is an ideal source or not. If it is an ideal source the answer is undefined because you would have an infinite current times zero ohms.

If the ac source is not ideal, the output would be zero.

If the diodes are ideal, there is no reverse leakage current, & no forward voltage drop. If the ac source is an ideal current source, the voltage across the diode pair is always zero, since 1 of the 2 diodes is forward biased.

If the ac source is an ideal voltage source, you get a paradox. A zero resistance perfect voltage source is loaded by a perfect diode with zero voltage drop, resulting in the current ramping up towards infinity.

Claude

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