How much current can the regulated 3.3 Vcc be tapped for with the FEZ Lemur?

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Hi
How much current can the regulated 3.3 Vcc be tapped for with the FEZ Lemur?
If there are any questions or suggestions please let me know.
Thanks
Gus50310

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the VREG is a jellybean LM1117, and they notionally can provide a max of 800ma. Depending on what you’re trying to achieve, you may find you can’t get that high (heat dissipation in an enclosed area for example)

welcome to the forum, enjoy your Lemur

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The LM1117MP regulator that it uses has a maximum output of 800mA. However, that will be limited by the limits of your power supply. The Lemur datasheet doesn’t list its max power requirements but let’s say its no more than 50mA for the controller and you’re not using the SD card. Personally, I’d reserve 100 mA for the board and use whatever’s left for the peripherals. So, if you’re plugged into a cheap laptop that barely supplies 500mA then you could probably use 400mA for your peripherals. If you’re powered through the barrel connector to a 1A wall wart then you could use maybe 700mA. If you need more than that, you need to think about giving the hungry peripherals their own regulator.

EDIT: I get up to go put the kids to bed and Brett jumps in there… :wink:

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800mA but there will be heat issues. I can get 200mA additional to what is used on the FEZ board usually, without heat issues.

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HI Gus, ianlee74 and Brett
Thanks for taking the time to reply. That gives me the info I need.