The TPS54531DDAR device is a 28-V, 5-A, step-down (buck) converter with an integrated high-side n-channel MOSFET. To improve performance during line and load transients, the device implements a constant-frequency, current mode control which reduces output capacitance and simplifies external frequency compensation design.
The TPS54531DDAR device has a preset switching frequency of 570 kHz.
The TPS54531DDAR device requires a minimum input voltage of 3.5 V for normal operation. The EN pin has an internal pullup current source that can be used to adjust the input-voltage undervoltage lockout (UVLO) with two external resistors. In addition, the pullup current provides a default condition when the EN pin is floating for the device to operate.
The operating current is 110 μA (typical) when not switching and under no load. When the device is disabled, the supply current is 1 μA (typical).The integrated 80-mΩ high-side MOSFET allows for high-efficiency power-supply designs with continuous output currents up to 5 A.
TPS54531DDAR 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
Feature
- 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 5-A Continuous Output Current
- High Efficiency at Light Loads with a Pulse Skipping Eco-mode?
- Fixed 570kHz Switching Frequency
- Typical 1μA Shutdown Quiescen 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
- Available in Easy-to-Use Thermally Enhanced 8-Pin SO PowerPAD? Package
The TPS54531 device is a 28-V, 5-A non-synchronous 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 under-voltage lockout. An overvoltage transient protection circuit limits voltage overshoots during startup and transient conditions. A cycle-by-cycle current-limit scheme, frequency fold back, and thermal shutdown protect the device and the load in the event of an overload condition. The TPS54531 device is available in 8-pin SO PowerPAD? package that has been internally optimized to improve thermal performance.
