Atmega128 ADC pin voltage range

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Hello,

 

I am working on the ATmega128 microcontroller. I want to know that what is the voltage range of ADC pin? Is it possible to give -5v on the ADC pin?

 

Waiting for your reply.

 

Thank you.

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Last Edited: Wed. May 5, 2021 - 09:03 AM
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No to negative voltages. The datasheet specifies the input range.

Ross McKenzie ValuSoft Melbourne Australia

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Is it 3v-3.6v operating voltage range for ADC?

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I guess you will not read the datasheet yourself, so read this.

 

Ross McKenzie ValuSoft Melbourne Australia

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It's all given here:

 

So the actual input can only be from GND to Vref then Vref itself can only be from 2.0V to AVcc and AVcc can only be in the range Vcc +/- 0.3V.

 

So say Vcc is 5.0V then AVcc could be up to 5.3V so the Vref could be between 2.0V and 5.3V and hence the input could be in the range 0V..2.0V to 0V..5.3V

 

It can never be negative. That is further emphasised by:

 

 

I'm no electrical engineer but I think you will find that op-amps are usually employed to move a wider voltage range into "reading range".