So this is a weird one... I am working on a device that has two different things, and one needs 4.5v and one needs 1.5v.
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@rasterweb spark fun and similar places probably have something that would work here, using a more modern brand name chip
@rasterweb If you’re okay with 1.8V output voltage, this thing here has a chip that claims 90 microamp quiescent current (>100k hours on an AA cell) and doesn’t cost too much: https://www.sparkfun.com/sparkfun-buck-regulator-breakout-1-8v-ap3429a.html
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@ottaross I did think about a voltage drop via resistor but it seemed like dropping from 4.5 to 1.5 might waste quite a bit of energy... (But I am not an expert on these things!)
@rasterweb yeah could bleed off a bit of energy depending on how much current needed.
If not needed urgently, and you had time to source a couple of cheap efficient regulators, that's prob the best path, but of course more parts, complexity.
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So this is a weird one... I am working on a device that has two different things, and one needs 4.5v and one needs 1.5v.
Is there any reason I could not just solder a wire in place to just get power from one cell and also use the existing wire to provide 4.5v elsewhere?
I know this isn't the best way to do it, but it's a quick hack to make something work... I can't find an issue with it under that condition. Can you?
@rasterweb the problem with these type of multi-tap situations is that when you drain the bottom cell faster, the other two cells can continue to provide current and reverse charge the first cell beyond zero and cause a leaky mess.
The ideal solution is to find a little DC-DC module that steps the 4.5V down to 1.5V.
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So this is a weird one... I am working on a device that has two different things, and one needs 4.5v and one needs 1.5v.
Is there any reason I could not just solder a wire in place to just get power from one cell and also use the existing wire to provide 4.5v elsewhere?
I know this isn't the best way to do it, but it's a quick hack to make something work... I can't find an issue with it under that condition. Can you?
@rasterweb as long as they're isolated I don't see why it wouldn't work.
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