SC4509SKTRT

Overview

The SC4509SKTRT is a synchronous step-down switching regulator manufactured by Semtech Corporation, belonging to the SC189 series. It operates with an input voltage range of 2.9 V to 5.5 V and delivers a fixed output voltage of 1.8 V at a maximum output current of 1.5 A. The device features a switching frequency of 2.5 MHz and utilizes a SOT-23-5 surface-mount package. It supports shutdown functionality and exhibits a load regulation of 1%. The operational temperature range spans from -40°C to +125°C, with a typical quiescent current of 7.5 mA.

Feature Summary

• Synchronous buck topology for high efficiency
• Integrated power switches within compact SOT-23-5 package
• Fixed 1.8 V output configuration
• Shutdown pin for power management control

Applications

• Portable consumer electronics requiring efficient DC-DC conversion
• Battery-powered devices needing stable 1.8 V rail
• Embedded systems with limited PCB space constraints

Procurement Notes

Verify that the specific suffix 'SKTRT' corresponds to the exact fixed 1.8 V output variant and SOT-23-5 packaging. Confirm RoHS compliance status through official manufacturer documentation or authorized distributor datasheets prior to ordering. Ensure the supplier provides traceable origin to avoid counterfeit components, as this part number may have multiple manufacturing revisions.

Selection Notes

Select this component when a fixed 1.8 V output is required without external feedback resistor programming. The 2.5 MHz switching frequency allows for smaller passive components compared to lower-frequency regulators. Consider the 1.5 A current limit and 5.5 V maximum input voltage when designing the power stage. Verify thermal performance in the target application environment given the small SOT-23-5 footprint.

Part Context

This part belongs to the SC189 family of synchronous step-down regulators from Semtech. These devices are designed for applications requiring high efficiency and small solution size. The SC189 series typically includes variants with different fixed output voltages and current ratings, all sharing similar control architecture and package options.

Replacement Considerations

Check Semtech's official replacement guide for direct cross-references. Variants such as SC189LSKTRT (if available) may offer identical electrical characteristics but require verification of output voltage and package compatibility.