On Mon, Feb 7, 2011 at 2:18 PM, Sebastien Lelong <[email protected] > wrote:
> Hi Vasile, guys, > > 2011/2/6 vasile surducan <[email protected]> > > >> A schottky is protecting the silly user only for reversing the polarity of >> the power supply, by blowing the fuse if it's reversed. >> > > After some more readings (like > http://qsysociety.org/qsywp/2010/12/diy-how-to-use-a-diode-to-provide-reverse-polarity-protection/or > http://highfields-arc.6te.net/constructors/other/revpolepro.htm or > http://jeelabs.org/2011/01/09/easy-electrons-%E2%80%93-diodes/), there > doesn't seem to be voltage drop when using fuse + diode like you suggested. > Diode should be overrated compared to the fuse, so it won't blow before the > fuse. In this case, a resettable fuse clearly is a good choice :) > > Since there's no voltage drop, why using Schottky diodes (since they're > also less resistant) ? What not just "usual" diodes like 1N4001 (or 1N4007) > ? > Oh boy, you own me a french wine and a french cheese next time I'll be at Paris (and seems will be soon). Until the fuse is blowing there is a voltage drop. And that voltage drop may kill everything on your board. That's why you need fast diode turn on and low voltage drop on that diode (which only schottky has) until the fuse blow ( meaning fast fuse blow, which a resettable fuse does not always assure...) Vasile > TIA > Seb > > -- > You received this message because you are subscribed to the Google Groups > "jallib" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/jallib?hl=en. > -- You received this message because you are subscribed to the Google Groups "jallib" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/jallib?hl=en.
