Buck controller for isolated or non-isolated rails
The MAX5069BAUE+ is a current-mode PWM controller designed for step-down (buck) converters, capable of driving an external transistor switch. Its output configuration supports both positive and isolation-capable designs, making it suitable for power supplies where galvanic isolation is required. Switching frequency is programmable from 50 kHz to 2.5 MHz, with clock sync input for aligning multiple converters. The 100% duty cycle capability allows the output to ride through input dips without dropout. Supply voltage range of 10.8 V to 24 V covers common intermediate bus rails in telecom and industrial systems.
Control features and package fit
Control features include dead-time control, enable, and frequency control, giving the designer flexibility to optimize efficiency and EMI across the load range. No synchronous rectifier driver is integrated, so an external MOSFET driver is needed for the high-side switch. Housed in a 16-TSSOP with exposed pad (0.173" width, 4.40 mm), the package provides a low thermal resistance path to the PCB copper plane. Surface-mount assembly with the exposed paddle soldered to a ground plane is required for full thermal performance. Single-output, single-phase topology — the controller regulates one rail. For multi-phase designs, multiple devices can be synchronized via the clock sync pin.
Supplied in tube packaging. For volume requirements, reel or tape-and-reel options may be available through the supply chain — confirm at quote time. Sourced through independent distribution channels; availability and current pricing confirmed against an RFQ. No pin-compatible second-source or official successor is recorded for this part number.