troubles with load from avr, need advice.

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Hi, I have an atmega 168 that supplies a device that should not pull much more then 100 Milli amps(should be able to measure this load soon). Normal I supply this device with USB current. however I'm forced to controller the load via 2 micro controller pins as I need to revers them for other applications. I noticed my device is pulling a bit more current that I hoped and the AVR is having trouble sustain it. I was wondering..

a) what is the max current out put of such a micro controller?
b) would using a buffer amplifier do that job, any recommendation?

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read the datasheet "absolute maximum ratings".

typically 40mA per pin, maximum per part will depend on the package.

Writing code is like having sex.... make one little mistake, and you're supporting it for life.

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Are you trying to turn the other device off and on under control of the AVR? If so you could use one of the ON Semi NUD3112 FET switches and use the power supply rail for the power source. Those devices will run off an I/O pin.

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thx glitch!

alwelch, I have a device that is power by pins PD3 and PD 4 for example. For device one its PD4 +5 and PD3 ground. device 2 is reversed. PD3 +5 and PD4 ground.

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There´s no way out, you need external components for this job..

regards,
Brunomuw

Regards,

Bruno Muswieck

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thought so, tnx.