Multi-topology PWM controller for isolated DC-DC
The Texas Instruments UCC28251RGPT is a current-mode PWM controller that handles Step-Up/Step-Down regulation across Full-Bridge, Half-Bridge, and Push-Pull topologies — one part number covers the transformer-coupled architectures you'd typically reach for in isolated DC-DC converters, bus converters, and telecom brick supplies. Its 42 kHz to 945 kHz switching frequency range lets you trade off magnetics size against switching losses: lower frequencies suit through-hole transformers with higher saturation flux, while the upper end shrinks the planar magnetics in a 20-QFN (4x4) footprint.
Operating temperature from -40°C to 125°C (TJ) is the full industrial junction-temperature grade. For a 60°C ambient enclosure with 20°C self-heating, you still have 45°C of thermal margin before hitting the 125°C limit — that headroom matters when the converter runs at high line and full load. Two PWM outputs with built-in synchronous rectifier drive let you eliminate the Schottky catch diode on the secondary side — the rectifier MOSFETs are driven in phase with the primary switching, which recovers the diode forward-drop loss and pushes efficiency into the mid-90s in a properly tuned full-bridge.
Active lifecycle and compliance documentation
ROHS3 Compliant means the part meets the current EU RoHS exemption scope, including the four phthalates.
