BB Power Supply Pot Problem (no not that pot)

by itsthemedication on Fri Mar 19, 2010 1:54 pm

I just put together the BB power supply, and only have 29 more to go. One reason for selecting this PS was for the adjustable voltage, i.e. I needed a STABLE 1.9 volts (don't ask). Anyway, if anyone else is thinking about this excellent little board and needs a voltage <3 I highly recommend ditching the single turn pot (very imprecise and possibly noisy as well) and replacing it with an 18 or 25 turn pot like Digikey 490-2914-ND (92 cents). The switched 3.3 and 5 volts work great by the way!
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Re: BB Power Supply Pot Problem (no not that pot)

by adafruit on Fri Mar 19, 2010 2:17 pm

nice hint! thanks for sharing! :)
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Re: BB Power Supply Pot Problem (no not that pot)

by toowongman on Fri Mar 19, 2010 9:44 pm

Don't those multi-turn trimpots have a limited life? I could be incorrect in reading the data sheet but it seems they're only rated for ~200 cycles/rotations?
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Re: BB Power Supply Pot Problem (no not that pot)

by Len17 on Fri Mar 19, 2010 10:56 pm

The way I read it, the resistance will change by no more than 3% after 200 rotation cycles.
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Re: BB Power Supply Pot Problem (no not that pot)

by toowongman on Sat Mar 20, 2010 1:05 am

Len17 wrote:The way I read it, the resistance will change by no more than 3% after 200 rotation cycles.

Cool, thanks for clearing that up :)
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