LDO40LPU50RY

Overview

The LDO40LPU50RY is a fixed-output low-dropout linear regulator manufactured by STMicroelectronics, delivering a stable 5 V output with a maximum load current of 400 mA. It operates within an extended input voltage range up to 38 V and features a typical quiescent current of 45 µA at no load. The device provides high power supply rejection ratio (PSRR) of 70 dB at 1 kHz and maintains low intrinsic noise performance of 20 µV RMS per volt of output voltage. Designed for harsh environments, it includes protection functions such as current limiting and thermal shutdown, ensuring reliable operation across a temperature range from -40 °C to +125 °C.

Feature Summary

• Ultra-low dropout voltage ensures efficient regulation even with minimal input-to-output differential.
• Low quiescent current consumption supports battery-powered applications requiring extended standby life.
• High PSRR and low noise characteristics provide clean power for sensitive analog and digital circuits.
• Integrated protection mechanisms including current limit and thermal shutdown enhance system safety.

Applications

• Automotive body and interior electronics active during parking mode
• Electronic modules remaining in active state when ignition is off
• Industrial applications with wide variations in power rail voltage
• Consumer applications requiring low-power linear regulation

Procurement Notes

Verify the specific package variant and marking code upon receipt to ensure alignment with design specifications. Confirm AEC-Q100 Grade 1 qualification status if automotive reliability is required. Check moisture sensitivity level handling procedures during storage and assembly. Ensure compatibility with wettable flank soldering processes for DFN6 packages. Validate input voltage ranges against actual circuit conditions to prevent overvoltage stress.

Selection Notes

Choose this regulator for applications demanding low static current and high input voltage tolerance. Consider its ultra-low dropout capability for efficiency optimization under varying load conditions. Evaluate the need for integrated protections against transient faults in critical systems. Assess thermal management requirements based on expected power dissipation at maximum load. Verify output voltage accuracy meets system precision requirements across the full operating temperature range.

Part Context

The LDO40LPU50RY belongs to the LDO40L family of low-dropout regulators designed for severe automotive and industrial environments. This series emphasizes low quiescent current and wide input voltage ranges, making it suitable for always-on applications. The family shares common features like AEC-Q100 qualification and compact DFN6 packaging with wettable flanks for improved solder joint visibility and reliability.

Replacement Considerations

NCV4276CDT50RKG is listed as a similar replacement option by onsemi. Verify pinout compatibility, output voltage accuracy, and thermal performance before substitution. Ensure the alternative component meets the same AEC-Q100 Grade 1 qualification standards if used in automotive contexts.