AD7705BR [Analog Devices]

The AD7705/AD7706 are complete analog front ends for low frequency measurement applications, featuring 2 fully differential input channels (AD7705) or 3 pseudo differential input channels (AD7706). They employ a Σ-Δ conversion technique to achieve up to 16 bits of no missing codes. The devices include a programmable gain front end (gains from 1 to 128) and a 3-wire serial interface compatible with SPI, QSPI, MICROWIRE, and DSP. They operate from 2.7 V to 3.3 V or 4.75 V to 5.25 V supplies, with power dissipation of 1 mW maximum at 3 V and standby current of 8 μA maximum. The devices are available in 16-lead PDIP, SOIC, and TSSOP packages. They feature a differential reference input and can handle unipolar input ranges from 0 mV to 20 mV up to 0 V to 2.5 V (with 5V supply and 2.5V reference) and bipolar ranges ±20 mV to ±2.5 V. Self-calibration and system calibration options eliminate gain and offset errors.