Using a delta-sigma architecture for 24 bits of no missing code performance, the ADS1240 a/d converter operates from 2.7V to 5.25V and consumes 570 µW of power. The device provides a four-channel multiplexer, burnout current sources, input buffer, offset d/a converter, and a programmable gain amplifier (PGA). The PGA delivers gains up to 128 and linearity error is guaranteed to be less than ±0.0015% of full scale. Other features include selectable data-output rate, a single conversion cycle settling filter, an external differential voltage reference, four programmable digital I/Os, and an SPI serial interface. A four-channel version (ADS1241) is also available. Price for the ADS1240 is $3.60 and the ADS1241 costs $3.95, each/1,000.