LDLN025J29R

Overview

The LDLN025J29R is a low-dropout linear voltage regulator from STMicroelectronics, designed for noise-sensitive applications. It delivers a fixed output voltage of 2.9 V with a maximum output current of 250 mA. The device operates within an input voltage range of 1.5 V to 5.5 V and features ultra-low output noise of 6.5 µVRMS. Key electrical parameters include a typical dropout voltage of 120 mV at full load, a quiescent current of 12 µA, and high power supply rejection ratios of 80 dB at 100 Hz and 60 dB at 100 kHz. It includes logic-controlled shutdown with consumption below 1 µA, internal soft-start, and protection against overcurrent and thermal overload.

Feature Summary

• Ultra-low output noise suitable for precision analog circuits
• Logic-controlled electronic shutdown for extended battery life
• High power supply rejection ratio for clean power delivery
• Integrated short-circuit and thermal protection mechanisms

Applications

• Powering precision Analog-to-Digital Converters (ADCs)
• Supplying Voltage-Controlled Oscillators (VCOs) in mobile devices
• Powering sensors in wireless IoT devices
• Noise-sensitive loads in smartphones and tablets

Procurement Notes

Verify the specific suffix 'J' corresponds to the required package type and tape/reel configuration before ordering. Confirm that the fixed 2.9 V output matches the system design requirements exactly, as adjustable variants exist within the same series. Ensure compatibility with the intended PCB footprint for the FlipChip-4 package.

Selection Notes

Select this component when ultra-low noise performance is critical for sensitive RF or analog loads. The 2.9 V fixed output eliminates the need for external resistors, simplifying the design. Consider the 12 µA quiescent current for battery-operated applications requiring long standby times. Verify that the 250 mA current capability meets the peak load demands of the target circuit.

Part Context

This part belongs to the LDLN025 series of low-dropout regulators. The series is characterized by its ability to provide stable, clean power to ultra-sensitive loads while maintaining low power consumption. It is widely used in space-constrained portable electronics where both performance and efficiency are paramount.

Replacement Considerations

Other parts in the LDLN025 series with different output voltages or package options may serve as alternatives if the 2.9 V output is not strictly required. Verify pinout compatibility and thermal characteristics when substituting with other LDO regulators from the manufacturer.