LD1085V33

Overview

The LD1085V33 is a fixed positive low-dropout linear voltage regulator manufactured by STMicroelectronics. It provides a stable 3.3 V output with a maximum load current of 3 A. The device supports input voltages up to 30 V and operates within a junction temperature range of -40 °C to +125 °C. Key electrical parameters include a line regulation of 6 mV, load regulation of 15 mV, and a maximum dropout voltage of 1.5 V at full load. The quiescent current is specified at 10 mA. It is housed in a 4-pin (3+Tab) D2PAK surface-mount package.

Feature Summary

• Provides a fixed 3.3 V output with high current capability up to 3 A
• Operates with an input voltage range extending up to 30 V
• Features internal thermal overload protection and safe operating area protection

Applications

• Point-of-load regulation for digital logic circuits
• Power supply stages for embedded microcontrollers
• Battery-powered equipment requiring efficient voltage conversion

Procurement Notes

Verify the specific suffix against the manufacturer datasheet to confirm pinout compatibility and thermal pad configuration. Ensure the selected package variant matches the intended PCB footprint and mounting requirements. Cross-reference the exact part number with official ST documentation to validate regulatory compliance status and environmental certifications prior to integration.

Selection Notes

Select this component when a fixed 3.3 V rail is required with high current delivery capabilities. The D2PAK package offers suitable thermal dissipation for moderate power applications. Consider the 1.5 V dropout voltage at 3 A when determining the minimum required input voltage headroom for the specific circuit design constraints.

Part Context

This device belongs to the LD1085 series of positive low-dropout regulators. The series includes variants with different output voltages and packages, such as TO-220 and SOT-223. The LD1085 family is designed to replace traditional 78xx regulators while offering improved performance in terms of dropout voltage and thermal stability under heavy load conditions.

Replacement Considerations

Compatible substitutes include the LD1085T33R and LD1085D2M33R from STMicroelectronics. Verify that alternative sources match the 3 A current rating and 3.3 V fixed output specification. Confirm package equivalence if physical interchangeability is required.