ADS7870

The ADS7870(1) is a complete low-power data acquisition system on a single chip. It consists of a 4-channel differential/8-channel single-ended multiplexer, precision programmable gain amplifier, 12-bit successive approximation analog-to-digital converter and a precision voltage reference. The programmable-gain amplifier provides high input impedance, excellent gain accuracy, good commonmode rejection, and low noise. For many low-level signals, no external amplification or impedance buffering is needed between the signal source and the A/D input.

The offset voltage of the ADS7870 PGA is auto zeroed. Gains of 1, 2, 4, 5, 8, 10, 16 and 20V/V provide 16-bit dynamic range and allow signals as low as 125mV to produce full scale digital outputs.

The ADS7870 contains an internal reference, which is trimmed for high initial accuracy and stability vs temperature. Drift is typically 10ppm/°C. An external reference can be used in situations where multiple ADS7870s share a common reference. The serial interface allows the use of SPI™, QSPI™, Microwire™, and 8051-family protocols, without glue logic.