TPS54331
3A synchronous buck converter with integrated MOSFETs, 3.5V-28V input range, and 95% peak efficiency for industrial p...
Product Overview
Description
The TPS54331 is a high-efficiency synchronous step-down converter featuring integrated N-channel MOSFETs and advanced Eco-mode control.
With input voltage range from 3.5V to 28V and adjustable output down to 0.8V, it serves diverse applications from industrial to consumer electronics.
The device offers fixed 570kHz switching frequency, cycle-by-cycle current limiting, and thermal shutdown protection for robust operation.
Product Series
TPS
Primary Application
Industrial power supplies
Key Features
- Integrated 80mΩ high-side and 50mΩ low-side MOSFETs
- Eco-mode for high efficiency at light loads
- Cycle-by-cycle current limiting
- Thermal shutdown and UVLO protection
- Adjustable soft-start
Specifications
| Input Voltage | 3.5V to 28V |
|---|---|
| Output Voltage | 0.8V to 22V |
| Output Current | 3A |
| Switching Frequency | 570kHz fixed |
| Efficiency | Up to 95% |
| Package | SOIC-8 |
Applications
Industrial power supplies
Industrial automation and control
Consumer electronics
Consumer electronics
Set-top boxes
Electronic system design
CPE equipment
Electronic system design
Test equipment
Electronic system design
FAE Expert Insights
"Based on my 15 years of experience supporting hundreds of TI power management designs, the TPS54331 demonstrates excellent performance and reliability in its target applications. This device has been successfully deployed in numerous customer designs with very positive feedback. Its key advantages include outstanding conversion efficiency, comprehensive protection features, excellent thermal performance, and flexible configuration options. I highly recommend this device for demanding industrial and automotive applications, especially where high reliability and long lifetime are required. Through BeiLuo, you can also access our FAE team's full technical support services, including solution selection, schematic review, debugging assistance, and production support."
High-performance power management solution of choice
— David Chen, BeiLuo
Frequently Asked Questions
What is the maximum output current of TPS54331?
The TPS54331 is rated for 3A continuous output current with proper thermal management. The integrated 80mΩ high-side and 50mΩ low-side MOSFETs support this current level with minimal conduction losses. For reliable operation, ensure adequate PCB copper area for heat dissipation and maintain junction temperature below 125C. The device features cycle-by-cycle current limiting to protect against overcurrent conditions. Actual maximum current depends on thermal design and ambient temperature conditions.
For applications requiring more than 3A, consider the TPS54335 (5A) or contact us for higher current solutions.
How do I calculate the efficiency of TPS54331?
Efficiency is calculated as Pout/Pin x 100%. For the TPS54331, typical efficiency ranges from 85% at light loads to 95% at full load. Key loss mechanisms include MOSFET conduction losses (I²R), switching losses, and gate drive losses. At 5V input and 3.3V/3A output, expect approximately 92-94% efficiency. The Eco-mode feature maintains high efficiency (>80%) even at 10% load, making it ideal for battery-powered applications. Use TI's WEBENCH Power Designer for accurate predictions.
Use TI's WEBENCH Power Designer for accurate efficiency predictions based on your operating conditions.
What is the recommended PCB layout for TPS54331?
Proper PCB layout is critical for stable operation. Place input capacitors close to VIN and GND pins. Keep the switching node (PH) trace short and away from sensitive analog circuits. Use a ground plane for thermal management and noise reduction. Place output capacitors near the load. Minimize the loop area formed by input capacitor, high-side MOSFET, and low-side MOSFET. Use thermal vias under the exposed pad for improved heat dissipation. Reference the TPS54331EVM evaluation module layout.
Reference the TPS54331EVM evaluation module layout or contact our FAE team for layout review services.
Can TPS54331 operate at 100% duty cycle?
The TPS54331 has a maximum duty cycle of approximately 95%, which limits the minimum input-to-output voltage ratio. For dropout operation where Vin approaches Vout, the high-side MOSFET remains on for the maximum allowed time. The minimum input voltage required is approximately Vout + 0.5V (accounting for MOSFET drop and margin). For applications requiring lower dropout, consider using an LDO in parallel or selecting a device with 100% duty cycle capability like the TPS54335.
For dropout-sensitive applications, evaluate the minimum input voltage requirements carefully or consider LDO post-regulation.
What protection features does TPS54331 include?
The TPS54331 includes comprehensive protection features: cycle-by-cycle current limiting protects against output overload, thermal shutdown disables the device at 165C junction temperature with 15C hysteresis, UVLO prevents operation at insufficient input voltage (typically 2.6V rising), and hiccup mode protects against sustained overcurrent. These features ensure robust operation in harsh industrial environments and prevent catastrophic failures during fault conditions.
The built-in protections make TPS54331 suitable for industrial applications. Contact us for additional protection requirements.
How do I select output capacitors for TPS54331?
Output capacitor selection affects output ripple, transient response, and stability. For TPS54331, ceramic capacitors (X5R/X7R) are recommended. Calculate minimum capacitance based on ripple requirements: Cout_min = ΔIL / (8 x fsw x ΔVout). For 3A output with 30% ripple current at 570kHz targeting 1% ripple, approximately 20-47µF is typical. Consider transient load requirements - larger capacitance improves load step response. ESR should be low (<10mΩ) for ceramic capacitors.
Use TI's capacitor selection guidelines or WEBENCH for optimized component values for your specific requirements.