ATmega8 ADC on stk500

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#1
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I think perhaps that I am missing the forest thru the trees...I am using experimenting with an atmega8 and ADC on an stk500. How where do I connect avcc? I have been looking thru the data sheet for the atmega8 and the user guide for the stk500, but I must be missing the pertinent sections.

Russ

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Datasheet, Figure 96. ADC Power Connections.
If you don't need high accuracy, you can replate the inductor by an resistor or connect AVCC directly to VCC.

/Martin.

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In AVR Studio have a look at the "Tools" section of Help. Within that is the help for STK500 and on the last page of it is a link to the PDF copy of the STK500 schematic. Open that link and in your PDF viewer take a look at page 4 of 9. To the left you will see how AVTG is related to VTG (basically through an inductor L400). So you don't need to do anything - the STK500 already brings AVTG to pin 20 of the mega8 socket for AVcc

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Surely AVcc is already routed to your mega8 on the STK500. You can vary the value of AVref via Studio.

The STK500 docs show the jumper settings for AVref.

Bear in mind that some AVR Analog Reference settings are not compatible with an external voltage on the AVref pin. e.g. you remove the jumper.

David.

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Thank you.

Russ