LDS3985M28R

Overview

The LDS3985M28R is a fixed-output Low Dropout (LDO) linear voltage regulator manufactured by STMicroelectronics. It provides a stable 2.8 V output with a maximum continuous current capability of 0.55 A. The device utilizes a 5-pin SOT-23 surface-mount package and operates within an input voltage range of 2.5 V to 6 V. Key electrical characteristics include a typical dropout voltage of 150 mV at full load, a maximum absolute input voltage rating of 6 V, and a line regulation of 0.0075%. The component is RoHS compliant and designed for applications requiring low noise and efficient power management in compact form factors.

Feature Summary

• Fixed 2.8 V output voltage configuration
• High current drive capability up to 0.55 A
• Ultra-low dropout voltage performance
• Logic-controlled electronic shutdown function

Applications

• Battery-powered portable electronics
• Cellular phones and mobile devices
• Personal digital assistants (PDAs)
• Cameras and camcorders
• Low-noise sensor power supplies

Procurement Notes

Verify the specific suffix 'M28R' against official STMicroelectronics documentation to confirm the 2.8 V fixed output variant. Ensure the ordering code matches the required tape-and-reel packaging format. Cross-reference the datasheet revision date to validate thermal and electrical specifications prior to integration into final designs.

Selection Notes

Select this component when a fixed 2.8 V rail is required with moderate current demands up to 550 mA. It is suitable for replacing older LDOs in space-constrained designs due to its small SOT-23 footprint. Consider the 6 V maximum input limit when designing for higher supply voltages. Evaluate thermal dissipation requirements based on the voltage differential between input and load currents.

Part Context

This part belongs to the LDS3985 family of ultra-low drop regulators from STMicroelectronics. The family shares common features such as low quiescent current, internal current limiting, and thermal shutdown protection. Variants within the series differ primarily by their fixed output voltage options, which typically include 1.8 V, 2.5 V, 2.8 V, 3.0 V, 3.3 V, and 5.0 V configurations.

Replacement Considerations

Compatible substitutes include other 2.8 V LDOs in SOT-23-5 packages with similar current ratings. Verify pinout compatibility and thermal performance characteristics before substitution. Check for equivalent shutdown logic functionality if power management control is required in the application.