The OP113 family of single supply operational amplifiers features both low noise and drift. It has been designed for systems with internal calibration. Often these processor-based systems are capable of calibrating corrections for offset and gain, but they cannot correct for temperature drifts and noise. Optimized for these parameters, the OP113 family can be used to take advantage of superior analog performance combined with digital correction. Many systems using internal calibration operate from unipolar supplies, usually either 5 V or 12 V. The OP113 family is designed to operate from single supplies from 4 V to 36 V, and to maintain its low noise and precision performance. The OP113 family is unity gain stable and has a typical gain bandwidth product of 3.4 MHz. Slew rate is in excess of 1 V/s. Noise density is a very low 4.7 nV/Hz, and noise in the 0.1 Hz to 10 Hz band is 120 nV p-p. Input offset voltage is guaranteed and offset drift is guaranteed to be less than 0.8 V/C. Input common-mode range includes the negative supply and to within 1 V of the positive supply over the full supply range. Phase reversal protection is designed into the OP113 family for cases where input voltage range is exceeded. Output voltage swings also include the negative supply and go to within 1 V of the positive rail. The output is capable of sinking and sourcing current throughout its range and is specified with 600 loads. Digital scales and other strain gage applications benefit from the very low noise and low drift of the OP113 family. Other applications include use as a buffer or amplifier for both A/D and D/A sigma-delta converters. Often these converters have high resolutions requiring the lowest noise amplifier to utilize their full potential. Many of these converters operate in either single supply or low supply voltage systems, and attaining the greater signal swing possible increases system performance.