Mega48 /ADC /AREF /STK500

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I am going to use the mega48's ADC and it's 1.1V internal reference but I am not sure of a few things.

For the finished project:

I understand I should connect a capacitor (.01uf ok?) to ground from the AREF

I don't know if AVCC should be connected to VCC

While testing on the stk500 board.
Do I just remove the AREF jumper or should I add a capacitor from the pin that connects to AREF to ground.

I will be measuring the voltage from a solar panel through a 10k - 2.2k to ground voltage divider so that a 3.5V panel voltage will be in the 630mv range. I plan to use 1V or higher reading as the turn system off signal and under 600mv as the on point.

I have used the ADC on tiny13's but the setup on the AREF and AVCC pins is a little unclear.

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Hey,

A 0.01uF should be fine.

AVCC *MUST* be connected to VCC. If you want you can add a filter in the form of inductor in there, but if your VCC is pretty clean (supplied by regulator, no big loads on it) you can just connect them directly.

For the STK500 it should be enough to just pull that jumper. The 0.01uF cap is just for better performance, it will still work fine without it.

Regards,

-Colin

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Just finished it works perfect, thanks.