LD39115J30R

Overview

The LD39115J30R is a fixed-output low-dropout linear regulator manufactured by STMicroelectronics. It provides a fixed output voltage of 3.0 V with a maximum continuous output current of 150 mA. The device operates within an input voltage range of 1.5 V to 5.5 V and features a typical dropout voltage of 80 mV at full load. Key electrical parameters include a quiescent current of 50 µA, a power supply rejection ratio (PSRR) ranging from 67 dB to 74 dB between 1 kHz and 10 kHz, and an operating temperature range of -40°C to +125°C. It utilizes a 4-bump flip-chip package measuring 0.79 x 0.79 mm.

Feature Summary

• Ultra-low dropout voltage capability for efficient battery-powered operation
• Very low quiescent current consumption to extend battery life
• Logic-controlled enable function for electronic shutdown
• Integrated short-circuit current limiting and thermal protection

Applications

• Low-power portable consumer electronics
• Battery-operated sensor nodes
• Wearable health monitoring devices
• IoT communication modules

Procurement Notes

Verify the specific suffix 'R' indicates reel packaging when ordering. Confirm the 3.0 V output variant matches the design requirement, as this series offers multiple fixed voltages. Check current stock status as availability may vary. Ensure the 4-bump flip-chip footprint is compatible with the target PCB layout before finalizing procurement.

Selection Notes

Select this component for applications requiring a compact form factor and stable 3.0 V rail under light loads. The low noise characteristic supports sensitive analog circuits. Verify that the input voltage remains above the minimum threshold while accounting for dropout variations. Consider the thermal performance in enclosed spaces due to the small package size.

Part Context

This part belongs to the LD39115 family of ultra-low quiescent current LDO regulators. The family shares common architectural features including flip-chip packaging and robust protection mechanisms. Variants differ primarily in their fixed output voltage settings, allowing designers to choose specific rails without external resistors while maintaining consistent physical dimensions and control logic.

Replacement Considerations

Direct substitutes include LP5900TL-3.0/NOPB from Texas Instruments. Verify pinout compatibility and thermal characteristics when transitioning between manufacturers. Ensure the replacement maintains the required 150 mA output current and low dropout specifications.