A low-voltage micropower JFET/bipolar operational amplifier

A single cell supply (operable down to 1.2 V) micropower operational amplifier using compatible low pinchoff voltage JFET´s (V/SUB p/=0.4 V) in conjunction with standard bipolar technology has been developed. The subvolt pinchoff JFET´s have proved useful in the common-mode feedback-assisted biasing of a simple p-n-p input stage to permit single supply operation, the design of a low-voltage high-performance current mirror and a differential to single-ended converter. The amplifier exhibits excellent ac performance (unity gain slew rate=0.25 V//spl mu/s, unity gain bandwidth=850 kHz) with low power dissipation (245 /spl mu/W).