Introduction

The TPS54331 device is a 28-V, 3-A nonsynchronous buck converter that integrates a low RDS(on) high-side MOSFET. To increase efficiency at light loads, a pulse skipping Eco-mode feature is automatically activated. Furthermore, the 1-μA shutdown supply-current allows the device to be used in battery-powered applications. Current mode control with internal slope compensation simplifies the external compensation calculations and reduces component count while allowing the use of ceramic output capacitors. A resistor divider programs the hysteresis of the input undervoltage lockout. An overvoltage transient protection circuit limits voltage overshoots during startup and transient conditions. A cycle-by-cycle current-limit scheme, frequency foldback and thermal shutdown protect the device and the load in the event of an overload condition. The TPS54331 device is available in an 8-pin SOIC package and 8-pin SO PowerPAD package that have been internally optimized to improve thermal performance.

Features

3.5 to 28-V Input Voltage Range

Adjustable Output Voltage Down to 0.8 V

Integrated 80-mΩ High-Side MOSFET Supports up to 3-A Continuous Output Current

High Efficiency at Light Loads With a Pulse Skipping Eco-mode

Fixed 570 kHz Switching Frequency

Typical 1-μA Shutdown Quiescent Current

Adjustable Slow-Start Limits Inrush Currents

Programmable UVLO Threshold

Overvoltage Transient Protection

Cycle-by-Cycle Current Limit, Frequency Fold Back, and Thermal Shutdown Protection

Applications

Consumer Applications such as Set-Top Boxes, CPE Equipment, LCD Displays, Peripherals, and Battery Chargers

Industrial and Car-Audio Power Supplies

5-V, 12-V, and 24-V Distributed Power Systems