Linear Technology has developed a pair of 16bit delta sigma ADCs with integrated references that suit remote sensor battery-powered applications and industrial sensors monitoring temperature or pressure. The integrated reference suits these to space-constrained applications, as does their 3 x 3mm footprint.
The LTC2460 and LTC2462 are designed to measure single-ended and differential sensors respectively. The LTC2460's 1.25V reference enables it to measure a single-ended input from 0V to 1.25V, while the LTC2462 is capable of measuring a differential input up to 1.25V. Both devices operate from a single 2.7V to 5.5V supply and draw 2.5mA (max) supply current at the 60Hz maximum sample rate with the internal reference active.
Linear claims that these parts achieve excellent 16bit DC performance of 1LSB (Typ) integral nonlinearity error, 2.2uVrms transition noise and 0.25% gain error (max). They operate up to 60 conversions per second, making them applicable to temperature, pressure, voltage, or other low-frequency sensor signal measurement. After each conversion, the ADC enters a shutdown mode to maximise power efficiency, reducing supply current to less than 1.5mA (max). Supply current can be further reduced to less than 2uA (max) in sleep mode.
An additional feature is an input sampling network that reduces the dynamic input current to less than 50nA, enabling a range of external input filter and protection circuits.