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bobc / bobc_hardware

Various hardware projects
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RAMPS-FD: LM7812 gets very hot #30

Open fullTalgoRythm opened 7 years ago

fullTalgoRythm commented 7 years ago

When running @24v with JP102 -VSEL pins 1-2 selected I found that the 7812 is getting very hot. I could actually smell it even with a fan running. I believe this would be a fairly typical problem when trying to drop 12v over a linear regulator like this one. I know there are a number of workarounds and personally I replaced mine with a cheap buck converter (LM2596). I can see it is still spec'd so I thought maybe you could investigate some alternatives. Myself I wouldn't mind a separate input for board power / hotend & fans and then just supply my own power (I did briefly feed 12v in via pin 2 of JP102 but it was a messy solution). It's probably not what most others would want but would make a nice option.

vido89 commented 7 years ago

The only safe version of Ramps-FD is the V2.A, issued in February 2014 so Im assuming that you are using V1 REV A