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AMC FMC Carrier electronic and mechanical projects
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Replace D5 and D6 for a single higher forward current diode #14

Closed henrique-silva closed 7 years ago

henrique-silva commented 8 years ago

The SS16 schottky diode has a forward current limit set in 1A, which is less than needed for the AFC board fully operate with both FMC connected when powered from the ATX stand-alone connector.

Using 2 diodes in parallel is dangerous because if they have a slight unbalacing, one of them will start to drive more current and, consequently, heat more. The heating in a diode makes it drive even more current, resulting in a positive current feedback that ends with the diode burning up.

aylons commented 8 years ago

I agree.

To substitute it, I suggest a diode with at least 6A this list. I doubt the connector would withstand this current, though - It does see documentation at Molex website.

I actually liked this option from AVX, which is small and fits the bill. However, a more standard and bigger DO-214 (SMB or SMC) would be a better option, so we may change PN or manufacturer later.