LD1085D2M18R

Overview

The LD1085D2M18R is a fixed-output positive linear voltage regulator manufactured by STMicroelectronics. It provides a fixed output voltage of 1.8V with a maximum continuous output current of 3A. The device features a low dropout voltage, guaranteed at a maximum of 1.2V when operating at the full 3A load. It utilizes a TO-263-4 (D²Pak) surface-mount package and includes internal protection mechanisms against overcurrent and thermal overload.

Feature Summary

• Provides stable regulated output voltage under varying load conditions
• Capable of delivering up to 3A of continuous output current
• Maintains regulation with minimal input-to-output voltage difference
• Includes integrated thermal and current limiting protections

Applications

• General-purpose power supply regulation in electronic circuits
• Pre-regulation for switching converters
• Biasing stages in communication equipment

Procurement Notes

Verify the specific suffix 'R' indicates tape-and-reel packaging configuration distinct from cut-tape or tube variants. Confirm the fixed 1.8V output specification matches the design requirement, as other suffixes in the LD1085 family denote different voltages or adjustable configurations. Ensure the D²Pak-3 pinout aligns with the target PCB footprint.

Selection Notes

Select this component when a fixed 1.8V rail is required with high current capability. The low dropout characteristic makes it suitable for applications where the input voltage cannot be significantly higher than the output. Consider the thermal dissipation requirements associated with 3A operation and the thermal resistance of the TO-263 package.

Part Context

This part belongs to the LD1085 series of low-dropout regulators designed for high-current applications. The series offers both fixed and adjustable output versions, sharing similar pinouts and protection features. The LD1085 is widely used in industrial and consumer electronics requiring efficient linear regulation.

Replacement Considerations

Direct pin-compatible replacements within the same manufacturer's portfolio include other LD1085 variants with different output voltages or adjustable settings, provided the electrical parameters meet the circuit requirements.