At 11:58 AM 30/03/2003, you wrote:
>>Schottky diodes can be appropriate in power supplies.  The biggest
>>impediment to more widespread use is their large reverse leakage current.
>>Even relatively "little" 1A diodes can have 20mA reverse leakage.  This
>>tends to be highly temperature dependent, so thing may appear to work fine
>>in the lab but fail in a less controlled environment.
>
>Interesting... That's one of those "little" things that wasn't mentioned in
>a power supply basics course I took recently.  Virtually every problem
>relating to SMPSs assumed the use of a Schottky diode, but no mention was
>made of reverse leakage current.

SMPS's use the Schottky's for the high switching speed, not so much
the lower forward voltage drop. Try using normal "slow" diodes in there
and you'll find it either won't work or will heat up & die really quick!
David...

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David Duffy        Audio Visual Devices P/L
U8, 9-11 Trade St, Cleveland 4163 Australia
Ph: +61 7 38210362   Fax: +61 7 38210281
New Web: www.audiovisualdevices.com.au
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