LM2673SX-3.3

Voltage Regulators - DC DC Switching Regulators Overview

The LM2673SX-3.3 is a SIMPLE SWITCHER® 3-A step-down voltage regulator from Texas Instruments, designed for high-efficiency DC-DC conversion. It operates with an input voltage range of 8V to 40V and provides a fixed 3.3V output at up to 3A load current. The device integrates a 260kHz switching frequency, enabling the use of compact external components. It features adjustable peak current limiting (2A to 5A) via an external resistor and includes thermal shutdown protection. Operating temperatures span from -40°C to +125°C.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Integrated power switch eliminates the need for external diodes or complex driver circuits
• Resistor-programmable peak current limit allows customization between 2A and 5A ranges
• Fixed 260kHz switching frequency minimizes required inductor and capacitor sizes
• Thermal shutdown protection safeguards the device during overload or overheating conditions

Voltage Regulators - DC DC Switching Regulators Applications

• Point-of-load regulation for embedded systems requiring 3.3V rails
• Battery-powered equipment utilizing wide input voltage ranges
• Industrial control systems needing robust step-down conversion
• Communication infrastructure power supplies

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the specific suffix (SX vs ST) to confirm package type (TO-263 vs TO-220). Confirm RoHS compliance status as indicated by NOPB suffix if applicable. Check datasheet revision dates for updated electrical characteristics. Ensure ordering information matches the exact output voltage variant (3.3V fixed). Validate manufacturer authenticity through authorized distribution channels.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when a fixed 3.3V output is required with up to 3A continuous current. Consider the 8V to 40V input range suitability for your supply source. Evaluate thermal management requirements given the TO-263 package and 3A load. Compare efficiency curves against alternative regulators for your specific duty cycle. Verify that the 260kHz frequency aligns with EMI constraints in your design.

Voltage Regulators - DC DC Switching Regulators Part Context

Part of the LM2673 SIMPLE SWITCHER family, which offers various fixed and adjustable output voltages. The SX suffix denotes the surface-mount TO-263 package variant. This series is known for simplifying power supply design through integrated protection features and minimal external component count. It serves as a drop-in replacement for older linear regulators in many high-current applications.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

LM2673SX-3.3/NOPB is the lead-free version of the same functional part. LM2673ST-3.3 is the through-hole TO-220 equivalent. Cross-reference pinouts carefully when substituting packages. Verify thermal performance differences between TO-263 and TO-220 enclosures.