Hello I am Jitendra Chaurasiya.
I am using AD9649 14 bit ADC in my circuit. The internal voltage reference of ADC is 1V and the differential analog input on VIN+ and VIN- 2Vp-p.
Also the absolute voltage on differential analog input VIN+, VIN− to AGND is −0.3V to AVDD + 0.2V given in datasheet.
So my question is: Whether the ADC input protected against its absolute rating? Because my input range is from -1.7V to 1.2V and after 1V Internal reference my input become from -0.7V to 2.2V which is out of it's range (as compared to -0.3V to (AVDD = 1.8) +0.2) which is -0.3 to 2V.
Kindly suggest me if any external protection required to protect my ADC analog input pins.
In the image below I used ADA4932 differential ADC driver with unity gain configuration.
Thanks and Regards,
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