AMC7891: ADC FULL Scale

David Ziv

Part Number: AMC7891

The AMC Has two input gain modes Vref & Vref x 2
Internal Vref = 2.5v

My setting use Internal Vref & Full Scale =Vrefx2
My Supply voltage AVDD = 4.85v

My question What is the Full scale? 5v or AVDD(4.85v)?

BR

David.

over 3 years ago

0 Paul_Frost over 3 years ago

TI__Guru 53633 points

Hi David,

The device can still detect up to 2×VREF, even if the supply is lower than that. Note that abs. max for the input pin is AVDD+0.3V, which should not be violated.

Thanks,

Paul

0 David Ziv over 3 years ago in reply to Paul_Frost

Intellectual 420 points

Hi Paul.

Detection was never the issue,
We are trying to measure as accurate voltage as possible.
So the V = DAC * FullScale/1023 is critical.

4.85v + 0.3, is a viable range

Appreciate you assistance.

0 Paul_Frost over 3 years ago in reply to David Ziv

TI__Guru 53633 points

Hi David,

The output would still be accurate to ~2×VREF (5V), even with a 4.85V supply.

Thanks,

Paul

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AMC7891: ADC FULL Scale