LM2679SDX-ADJ

Voltage Regulators - DC DC Switching Regulators Overview

The LM2679SDX-ADJ is a SIMPLE SWITCHER® monolithic integrated circuit designed as a high-efficiency step-down DC/DC switch regulator. It supports an input voltage range of 8V to 40V and delivers up to 5A of output current. The device features an adjustable output voltage, allowing flexibility in system design. Operating at a fixed switching frequency of 260kHz, it enables the use of compact external components. The regulator incorporates internal soft-start functionality to limit inrush current during startup and includes programmable current limiting for enhanced protection.

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.
• Features a built-in 260kHz fixed-frequency oscillator that facilitates the use of physically smaller passive components compared to lower frequency alternatives.
• Includes internal thermal shutdown and externally programmable peak current limiting to safeguard the device and load circuitry against fault conditions.

Voltage Regulators - DC DC Switching Regulators Applications

• Efficient pre-regulators for linear voltage regulators
• Direct battery charging systems
• High-performance point-of-load regulation modules

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the specific suffix configuration when sourcing this component, as variations exist within the LM2679 family regarding package type and output adjustability. Confirm that the procurement source provides documentation matching the exact part number to ensure compatibility with the intended 14-VSON surface-mount application. Cross-reference manufacturer datasheets to validate the presence of required safety features such as thermal shutdown and current limiting before finalizing orders.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this regulator when designing systems requiring a robust 5A buck converter with wide input voltage tolerance. The adjustable output capability allows customization for various logic levels or analog supply rails. Ensure the selected variant matches the required thermal management strategy, as the TO-263 or VSON packages handle significant power dissipation. Evaluate the need for external current limiting programming based on the maximum load requirements of the target application.

Voltage Regulators - DC DC Switching Regulators Part Context

This component belongs to the SIMPLE SWITCHER® series from Texas Instruments, originally developed by National Semiconductor. The LM2679 family is characterized by its ease of design and reliance on standard off-the-shelf inductors. While the broader series includes fixed-voltage options like 3.3V and 5.0V, the ADJ variant specifically targets applications needing precise voltage tailoring within the 1.2V to 37V range.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Direct replacements include other LM2679 variants with compatible pinouts and electrical characteristics. Verify that substitute parts maintain the same 260kHz switching frequency and 5A current rating to ensure performance parity in existing designs.