Multi-topology controller for isolated and non-isolated rails
The MAX669EUB+ is a current-mode PWM controller from Analog Devices that handles Boost, Flyback, and SEPIC topologies — three common architectures for generating a regulated output from a lower or varying input rail. Its 1.8 V to 28 V supply range (Vcc/Vdd) means it can run off a 3.3 V logic rail, a 5 V USB bus, or a 24 V industrial supply without an external bias regulator. The switching frequency spans 100 kHz to 500 kHz with clock sync capability, letting the designer place the switching harmonics in a clean band or synchronise multiple converters to a common clock for noise management.
90% duty cycle and isolation-ready output
Maximum duty cycle is 90 %, which sets the achievable step-up ratio — for a Boost converter running from 5 V input, the output can reach roughly 45 V before the duty-cycle ceiling limits the transfer. The output configuration is Positive, Isolation Capable — the controller can drive a transformer in Flyback topology to produce a galvanically isolated secondary rail, common in telecom and industrial auxiliary supplies. The single transistor-driver output (1 phase) drives an external N-channel MOSFET; no synchronous rectifier is built in, so the designer adds a Schottky catch diode on the output.
Active production — no lifecycle concern
The part is supplied in Tube packaging; date-code continuity is confirmed at order time against the specific lot.