5000-VRMS Isolated Error Amplifier Fits Functionality Into Tiny Package

The FOD2741 optically isolated error amplifier combines an optocoupler, a precision reference, and an error amplifier in an eight-pin, dual-inline package. The amplifier is the functional equivalent of a KA431 shunt voltage regulator and a CNY17F-3 optocoupler in a single space-saving device. The FOD2741's high 5000-V_RMS isolation voltage suits it for offline power-conversion applications. It provides isolated voltage feedback between the secondary and primary sides of power-conversion circuits for control and regulation purposes. The amplifier can team with one of the company's power switches or power-management devices to simplify switch-mode power-supply and dc-dc converter designs. The FOD2741 features a 2.5 V_REF with 0.5%, 1%, and 2% tolerance options. In addition to a low temperature coefficient of 50 ppm/°C maximum, the device offers a current transfer ratio of 100% to 200%. The FOD2741 carries UL, CSA, VDE, and BSI safety agency certifications. Both through-hole and surface-mount lead configurations are available in 50-unit tube packaging. Surface-mount devices also are available in tape-and-reel packaging with 1000 units per 13-in. diameter reel. The FOD2741 amplifiers cost $0.30 each in 1000-unit quantities.