An extended input ADC accepts input signal ranges that are greater than the supply voltage. Maxim calls these products "Beyond-the-Rails" ADCs. ADCs that have the Beyond-the-Rails feature encompass both single supply ADCs with bipolar inputs, and products with input ranges that are higher than voltage supply inputs.
Products in this category contain power conversion functions that boost or invert voltage rails internally, reducing the number of required power rails. This power integration allows for a less complex design while providing significant reduction in design footprint.