Wide-input PWM controller for isolated and non-isolated rails
The LM5041BMTC/NOPB is a current-mode PWM controller that handles Step-Up/Step-Down regulation using Half-Bridge or Push-Pull topologies. Switching frequency is programmable to 200kHz or 600kHz — the lower frequency suits larger transformers with lower core loss, while 600kHz shrinks the magnetic footprint at the cost of higher switching losses in the FETs. With Synchronous Rectifier drive output, the controller can drive external SR FETs on the secondary side, cutting rectification losses by several points in a 3.3V or 5V output rail.
Control features that matter on the bench
Dead Time Control lets the designer set the non-overlap interval between the high-side and low-side FETs — too little dead time risks shoot-through, too much wastes duty cycle and increases body-diode conduction loss. Soft Start ramps the reference voltage at power-up, preventing output overshoot and inrush current from saturating the transformer core. Frequency Control allows the oscillator to be synchronised to an external clock via the Clock Sync pin, keeping the switching noise spectrum predictable in a multi-rail system. The single Transistor Driver output delivers a push-pull gate drive signal — the external FETs handle the power stage; the controller only manages the timing and feedback loop.
Package and temperature grade for the BOM
Housed in a 16-TSSOP (4.40mm width) with a 0.65mm pitch — the fine pitch demands a controlled-impedance PCB layout and a soldering profile that avoids tombstoning. Supplied in Tube, not Tape & Reel, so pick-and-place lines need a tube feeder or a bulk-to-tape conversion step. The wide temperature range also means the oscillator and error amplifier drift less over the operating band.
ROHS3 compliant, so it ships without exemption paperwork for EU and UKCA markets.