Loading…
SOP-8 · TPS54331
ActiveDC-DC Buck Converters
TPS54331
Texas Instruments · SOP-8 · DC-DC Buck Converters
Price on Request
Get a competitive quote within 24 hours. Volume discounts available. Shenzhen stock ships in 1-2 business days.
Overview
The TPS54331 is a 28 V, 3 A step-down (buck) switching regulator from Texas Instruments with integrated high-side and low-side power MOSFETs, operating at a fixed 570 kHz switching frequency. It delivers up to 90% efficiency in typical 12 V-to-5 V or 24 V-to-3.3 V conversions, in a compact SOP-8 (PowerPAD) package that measures just 5×6 mm. This makes it the modern replacement for the ancient LM2596 (which is TO-263 and 60% efficient) in industrial, telecom and consumer power applications.
Key features: input voltage range 3.5 V to 28 V (up to 32 V absolute max, so it survives automotive 24 V transients), 3 A continuous output current (4 A peak), internal soft-start (typically 1 ms), enable pin with 5 µA shutdown current, cycle-by-cycle current limit, thermal shutdown at 165 °C, and Eco-mode for light-load efficiency (drops to burst operation under 100 mA load).
The 570 kHz fixed frequency is a good compromise — high enough to allow small inductors (10-22 µH) and ceramic output capacitors, low enough to keep switching losses and EMI manageable. Layout is straightforward: a single-layer PCB with proper ground plane and short high-current loops gives clean operation without shielding.
Feedback uses an external resistor divider referenced to the internal 0.8 V bandgap, so output voltage is programmable from 0.8 V to about 25 V. Common presets: 3.3 V (R1=31.6 kΩ, R2=10 kΩ), 5 V (R1=52.3 kΩ, R2=10 kΩ), 12 V (R1=140 kΩ, R2=10 kΩ).
Related parts: TPS54332 (3 A, 28 V, adjustable soft-start), TPS54340 (3.5 A, 42 V, higher Vin), TPS563200 (3 A, 17 V, SOT-23-6 for space-constrained), LM5017 (100 V, 600 mA for high-voltage low-current).
Our Shenzhen stock: TI TPS54331DR (SOP-8 with PowerPAD) MOQ 2,500 pcs on reel or 100 pcs loose.
Key Features
- 3.5-28 V input, 3 A output, up to 90% efficiency
- Integrated MOSFETs — no external switches needed
- Fixed 570 kHz switching for small magnetics
- Eco-mode for high light-load efficiency
Typical Applications
- Industrial 24 V to 5 V / 3.3 V point-of-load conversion
- Automotive 12 V to 5 V USB chargers and dashcam power
- Telecom line-card auxiliary supplies
- Solar charge controllers and battery management
- LED driver pre-regulators
Specifications
- Input Voltage
- 3.5 to 28 V
- Output Current
- 3 A
- Switching Frequency
- 570 kHz
- Topology
- Buck (Step-Down)
- Efficiency
- up to 90 %
- Integrated FETs
- Yes
- Operating Temperature
- -40 to 85 °C
- Mounting Type
- Surface Mount
- RoHS
- Compliant
Procurement Tips
For automotive or 24 V industrial applications with high input transients, spec the TPS54340 (42 V max input) instead of TPS54331 — same pinout, same package, only ~$0.20 more.
Frequently Asked Questions
TPS54331 vs LM2596 — which is better?
TPS54331 in almost every way: 3× smaller (SOP-8 vs TO-263-5), 90% efficiency vs 60%, integrated MOSFETs vs external, fixed 570 kHz vs 150 kHz (smaller inductors). LM2596 is only cheaper at very low volumes and has simpler layout. For new designs, always choose TPS54331 or TPS54340.
What inductor and capacitor do I need?
For 12 V in / 5 V out / 3 A: 22 µH inductor rated for 4 A saturation, plus 2× 22 µF X7R ceramic output caps and 1× 100 µF bulk electrolytic. Input needs 2× 10 µF X7R ceramics close to the VIN pin.
Why does my TPS54331 get hot at 2 A load?
Check three things: (1) PCB copper area on the exposed pad — needs at least 1 in² of copper with thermal vias to inner layers; (2) inductor saturation current — must be >1.3× peak load; (3) input capacitor ESR — ceramics required, not electrolytics. At 2 A with 12 V in / 5 V out, expect ~1.5 W dissipation.
Can I parallel two TPS54331 for 6 A output?
Not recommended. Buck converters in parallel need active current sharing, which TPS54331 lacks. For 6 A use TPS54620 (6 A single chip) or two independent 3 A rails feeding different loads.
What is Eco-mode?
At light loads (under ~100 mA), the converter enters burst mode — it skips switching cycles to reduce quiescent current from 4.5 mA to about 350 µA. Output ripple increases slightly (typically 20-50 mV pp) but efficiency at 10 mA load jumps from 30% to 70%.
MOQ and lead time?
MOQ 2,500 pcs on reel for TPS54331DR, or 100 pcs loose. TI authorized 12-20 weeks; Shenzhen stock 1-3 days.
Alternatives & Equivalents
View full cross-reference table →Need TPS54331 pricing and availability?
Submit an RFQ — we reply within 24 hours with stock, pricing, lead time and packaging options.
Request a Quote →