I am selecting between many ADCs these days. Sometimes the input range of ADC is in absolute value like ± 4V but sometimes it is written as 2.5 Vpp. I basically need a bipolar ADC for my application but I am confused whether a 2.5 Vpp would accept negative voltage or not?. As far as I am concerned the 2.5 Vpp could be ranging from a 0 V to 2.5 V centered around 1.25 V. or it could be from -1.25 V to + 1.25 V centered around 0V. I am stuck at this point and any kind of help would be highly appreciated.