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Unread 20-04-2008, 00:29
EricVanWyk EricVanWyk is offline
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Re: NEW 2009 Control System Released

Quote:
Originally Posted by writchie View Post
These look like high-speed switch mode regulators. Large capacitors are not required, and can even be detrimental. Since the 24V supply is an up-converter, it can probably maintain regulation down to 7V on the main battery, maybe even less.
100% Correct.

The 24V supply is an LM3478 running at 600kHz. As you said, it is a boost (up) converter.

It can survive well below 7V input.

You are correct in saying that for some controllers, large bulk capacitance is not necessarily a good thing. In fact, in some specific instances, they can hurt performance. For this particular controller, it would be fine to add big bulk capacitance.

However, it wouldn't really help that much. The problem with large capacitors is that they have poor frequency response. A big "can" capacitor is a less effective use of space / money than smaller ceramic caps are for the frequency it is switching at.
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