FEATURES
12-bit resolution 8 microsecond conversion times 5 input voltage ranges Internal high Z input buffer Short-cycle operation Internal precision 6.3 volts reference MIL-STD-883 models available BUFFER INPUT 30 +15V POWER 28 –15V POWER 31 BUFFER + AMPLIFIER BUFFER 29 OUTPUT Five input voltage ranges are programmable by external pin connection. An internal buffer amplifier is also provided for applications in which 50 M ohms input impedance is required. It utilizes a fast 12-bit monolithic DAC which includes a precision zener reference source. The circuit also contains a fast monolithic comparator, a monolithic 12-bit successive approximation register, a clock and a monolithic buffer amplifier. Nonlinearity is specified at ± 1/2LSB maximum. REF. OUT 18 +5V POWER 16 The ADC-85 can be short-cycled to give faster conversions in lower-resolution applications. Use of the internal buffer amplifier increases conversion time by 3 microseconds, the settling time of the amplifier.