4.5-V to 28-V, synchronous buck controller with voltage feed forward in HTSSOP package

The TPS40077 is a mid-voltage, wide-input (4.5-V to 28-V), synchronous, step-down controller, offering design flexibility for a variety of user-programmable functions, including soft start, undervoltage lockout (UVLO), operating frequency, voltage feed-forward, and high-side, FET-sensed, short-circuit protection.

The TPS40077 drives external N-channel MOSFETs using second-generation, predictive-gate drive to minimize conduction in the body diode of the low-side FET and maximize efficiency. Pre-biased outputs are supported by not allowing the low-side FET to turn on until the voltage commanded by the closed-loop soft start is greater than the pre-bias voltage. Voltage feed-forward provides good response to input transients and provides a constant PWM gain over a wide input-voltage operating range to ease compensation requirements. Programmable short-circuit protection provides fault-current limiting and hiccup recovery to minimize power dissipation with a shorted output. The 16-pin PowerPAD package gives good thermal performance and a compact footprint.