LD2979Z33

Overview

The LD2979Z33 is a fixed positive low-dropout linear voltage regulator from the STMicroelectronics LD2979 series, providing a nominal output of 3.3 V with a maximum load current of 50 mA. It operates within an input voltage range up to 16 V and features a very low dropout voltage of 400 mV at full load. The device incorporates logic-controlled electronic shutdown via a TTL-compatible inhibit pin, reducing quiescent current to near zero in off mode. Designed for stability with only a 1 µF ceramic capacitor, it includes internal current and thermal limiting protections.

Feature Summary

• Logic-controlled electronic shutdown function compatible with TTL levels
• Very low dropout voltage operation suitable for battery-powered systems
• Internal current and thermal limit protection mechanisms

Applications

• Low noise power supply applications
• Battery powered systems
• Local regulators requiring standby modes

Procurement Notes

Verify the specific suffix 'Z' against official ST documentation to confirm package type and environmental compliance status. Confirm availability as datasheet references indicate standard order codes like LD2979M33TR. Ensure the inhibit pin is not left floating during operation.

Selection Notes

Select this component when a fixed 3.3 V output is required with minimal external capacitance. The SOT23-5L package suits space-constrained designs. Verify that the application does not exceed the 50 mA output current limit or the 16 V maximum input voltage rating.

Part Context

This part belongs to the LD2979 series of very low drop voltage regulators. The series offers multiple fixed output voltages including 3.0 V, 3.3 V, 3.8 V, and 5.0 V. All variants share similar electrical characteristics and package options, differing primarily in their regulated output voltage levels.

Replacement Considerations

LD2979M33TR provides the same 3.3 V output and 50 mA capability within the same series.