LM2679S-ADJ

Voltage Regulators - DC DC Switching Regulators Overview

The LM2679S-ADJ is a monolithic integrated circuit from the SIMPLE SWITCHER® series, functioning as a 5A step-down DC/DC switching regulator. It accepts an input voltage range of 8V to 40V and provides an adjustable output voltage spanning 1.2V to 37V. The device operates at a fixed internal switching frequency of 260kHz, enabling the use of compact passive components. It features a TO-263-7 surface-mount package and supports a maximum output current of 5A with a single positive output configuration.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Integrates a low on-resistance DMOS power switch to achieve high conversion efficiency exceeding 90% under typical operating conditions.
• Incorporates a built-in 260kHz fixed-frequency oscillator that simplifies design by allowing smaller external inductors and capacitors.
• Includes programmable peak current limiting via external resistors, providing protection against short circuits and overloads.
• Features integrated thermal shutdown circuitry to safeguard the device and load during fault conditions or excessive temperature rise.

Voltage Regulators - DC DC Switching Regulators Applications

• Efficient pre-regulator for linear power supply systems
• Battery charging circuits
• Post-regulation for bus distribution networks

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify component authenticity through authorized Texas Instruments distributors or certified partners. Confirm the specific suffix matches the required package variant and lead-free status. Review the latest datasheet revision for any updates regarding electrical characteristics or recommended operating conditions before finalizing procurement specifications.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this component when designing buck converters requiring up to 5A continuous load current with flexible output voltage settings. Ensure the input voltage remains within the 8V to 40V operational window. Consider the thermal performance of the TO-263-7 package and implement adequate PCB copper area for heat dissipation to maintain reliability across the specified industrial temperature range.

Voltage Regulators - DC DC Switching Regulators Part Context

This part belongs to the LM2679 family of SIMPLE SWITCHER regulators, originally developed by National Semiconductor before its acquisition by Texas Instruments. The family includes fixed-output variants (3.3V, 5V, 12V) alongside the adjustable ADJ version. The LM2679S-ADJ specifically targets applications needing customizable voltage levels while maintaining the robust protection features and high efficiency characteristic of the series.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Direct substitutes include other LM2679S-ADJ variants with different packaging suffixes such as LM2679SX-ADJ/NOPB. Verify pin compatibility and thermal resistance requirements when cross-referencing with alternative manufacturers' synchronous buck controllers, though non-synchronous operation differs significantly.