LD1117DT33

Overview

The LD1117DT33 is a fixed-output low-dropout linear voltage regulator manufactured by STMicroelectronics. It provides a stable 3.3V output with a maximum continuous current of 800mA. The device operates within an input voltage range up to 15V and features a typical dropout voltage of 1V at full load. It incorporates internal thermal overload and short-circuit protection mechanisms. The component utilizes a TO-252 (DPAK) surface-mount package with three pins, ensuring efficient heat dissipation through the exposed tab. It maintains high power supply rejection ratios and tight output voltage tolerance.

Feature Summary

• Integrated thermal overload and short-circuit protection for enhanced reliability
• Low dropout voltage characteristic enabling efficient operation with minimal input-to-output differential
• High efficiency design utilizing NPN pass transistor architecture

Applications

• Battery-powered systems requiring regulated 3.3V rails
• General-purpose positive voltage regulation in embedded electronics
• Post-regulation stages for switching power supplies

Procurement Notes

Verify the specific suffix designation against official datasheets, as variations such as 'TR' indicate tape-and-reel packaging while other suffixes may denote different handling or testing criteria. Confirm that the procurement source provides original manufacturer documentation to ensure authenticity. Cross-reference the part number with the latest STMicroelectronics product selection guide to validate availability and compliance with current environmental standards before finalizing orders.

Selection Notes

Select this component when a fixed 3.3V output is required with moderate current demands up to 800mA. Ensure the input voltage remains within the 15V maximum limit and consider the thermal performance of the DPAK package under expected load conditions. Verify that the application does not require adjustable output voltages, as this variant is fixed. Evaluate the dropout voltage requirements to ensure sufficient headroom between input and output voltages for stable regulation.

Part Context

This part belongs to the LD1117 series of low-dropout positive voltage regulators from STMicroelectronics. The series includes various fixed output voltages and adjustable versions, available in multiple packages including SOT-223, SO-8, and TO-220. The DT33 variant specifically denotes the 3.3V fixed output in the DPAK surface-mount package, designed for space-constrained applications requiring robust thermal management.

Replacement Considerations

The LD1117DT33CTR is a verified equivalent part number offering identical electrical specifications and pinout compatibility. When substituting, confirm that the alternative package type matches the PCB footprint and thermal requirements of the original design.