Texas Instruments has a 16-bit delta-sigma ADC with integrated programmable gain amplifier (PGA), reference, temperature sensor and 4-input multiplexer.
Measuring 2x1.5mm, the ADS1118 provides direct, linearised measurements with uncalibrated error guaranteed below 0.5 deg C from 0 degrees C to 65 deg C.
A built-in internal reference supports data rates up to 860 samples per second.
Power is from 2.0V to 5.5V supplies consuming 150µA (typical).