Input Diode Reverse Voltage

23 May 2012

I have been looking at the VIN circuit for the mbed and the diode used is a BAT60A. The spec sheet for this diode says that its reverse voltage protection is rated at 10V. However there is a note associated with this which shows a reverse voltage de-rating dependant on temperature above 25 degC. Am I right in thinking that there might be an issue with D1 if I supply 9V on VIN at about 40-50 degC? The BAT60A spec sheet says max Vr at 50 degC is 6.5V.

Any help or words of caution would be welcome :)

Awstriker

26 May 2012

Interesting question. The diode may conduct and the reverse diode current will be dependent of the temperature but the actual loads of the reverse diodes will be C10 and R15 so this will probably just increase the consumption a bit assuming that C5 in not rated for a low voltage. I don't think the FPF2123 will be damaged with 9v in its output but I'm not sure either.

Alex