FOD2742C

OPTICALLY ISOLATED ERROR AMPLIFIER FOD2742A DESCRIPTION The FOD2742 Optically Isolated Amplifier consists of the popular KA431 precision programmable shunt reference and an optocoupler. The optocoupler is a gallium arsenide (GaAs) light emitting diode optically coupled to a silicon phototransistor. It comes in 3 grades of reference voltage tolerance = 2%, 1%, and 0.5%. The Current Transfer Ratio (CTR) ranges from 100% to 200%. It also has an outstanding temperature coefficient of 50 ppm/°C. It is primarily intended for use as the error amplifier/ reference voltage/optocoupler function in isolated ac to dc power supplies and dc/dc converters. FUNCTIONAL BLOCK DIAGRAM FOD2742B FOD2742C When using the FOD2742, power supply designers can reduce the component count and save space in tightly packaged designs. The tight tolerance reference eliminates the need for adjustments in many applications. The device comes in a 8-pin small outline package. FEATURES Optocoupler, precision reference and error amplifier in single package 2.5V reference CTR 100% to 200% 2,500V RMS isolation UL approval E90700, Volume 2 VDE approval 136616 FOD2742A: tolerance 0.5% FOD2742B: tolerance 1% FOD2742C: tolerance 2% BSI approval 8661, 8662 CSA approval 1113643 NC 1 8 LED C 2 7 FB E 3 6 COMP NC 4 5 GND Low temperature coefficient 50 ppm/°C max APPLICATIONS Power supplies regulation DC to DC converters PIN DEFINITIONS Pin Number 1 2 3 4 5 6 7 8 Pin Name NC C E NC GND C...