The AD7707 is a complete analog front end for low frequency measurement applications. This three-channel device can accept either low level input signals directly from a transducer or high level ( 10 V) signals and produce a serial digital output. It employs a sigma-delta conversion technique to realize up to 16 bits of no missing codes performance. The selected input signal is applied to a proprietary programmable gain front end based around an analog modulator. The modulator output is processed by an on-chip digital filter. The first notch of this digital filter can be programmed via an on-chip control register allowing adjustment of the filter cutoff and output update rate. The AD7707 operates from a single 2.7 V to 3.3 V or 4.75 V to 5.25 V supply. The AD7707 features two low level pseudodifferential analog input channels, one high level input channel and a differential reference input. Input signal ranges of 0 mV to +20 mV through 0 V to +2.5 V can be accommodated on both low level input channels when operating with a VDD of 5 V and a reference of 2.5 V. They can also handle bipolar input signal ranges of 20 mV through 2.5 V, which are referenced to the LCOM input. The AD7707, with a 3 V supply and a 1.225 V reference, can handle unipolar input signal ranges of 0 mV to +10 mV through 0 V to +1.225 V. Its bipolar input signal ranges are 10 mV through 1.225 V.