k6ccc Posted November 10, 2011 Share Posted November 10, 2011 Hi all, I just received my first Servo Dog and I am seeing something when I look at the board that looks wrong to me as an electronics technician. There are 2 large heat sinks for the 2 voltage regulators. The issue is that the heat sinks are designed for a TO-220 case device, and the actual voltage regulators are far smaller. This means that there is a air gap of over 1/8 inches between the regulator and the heat sink. That means that the heat sink is doing absolutely nothing to cool the voltage regulator and the regulator is going to run very hot.My suspicion is that the board originally had a TO-220 case regulator (a very common package for voltage regulators) with an appropriate heat sink. Somewhere along the line, the voltage regulator was changed to a smaller package, but the larger heat sink remained.Am I making think straight here and is this a concern? Attached files Link to comment Share on other sites More sharing options...
The Pest Posted November 10, 2011 Share Posted November 10, 2011 I would agree with your diagnosis You might want to either start a service ticket or call the and ask. Before running it. Link to comment Share on other sites More sharing options...
LightORamaDan Posted November 10, 2011 Share Posted November 10, 2011 That is a surface mount heatsink it is not supposed to touch the case. It gets heat via copper traces on the board. Depending on the input voltage you will see a significant amount of heat generated.The heatsink is the correct one for the package.Best regards,DanLight O Rama, Inc. Link to comment Share on other sites More sharing options...
k6ccc Posted November 10, 2011 Author Share Posted November 10, 2011 Thanks for the answer Dan (and E-Mail response to the ticket I opened). I don't often work with surface mount ICs (too D#$%& small for my eyes and hands ), but now that I look at it, sure enough, there is a HUGE amount of PC board trace between the the IC and the "legs" of the heat sink.It caught my attention because I have seen a situation where a board maker substituted a different package IC and the heat sink did not work resulting in IC failure. Just making sure that this was the same situation and it had not been caught.In my case it's not really an issue as I don't expect to be driving servos with my ServoDog (I needed a bunch of inputs). Link to comment Share on other sites More sharing options...
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