STMicroelectronics LDQ44PURY 400mA High-Accuracy LDO Voltage Regulator

Introduction

The STMicroelectronics LDQ44PURY is a compact low-dropout (LDO) linear voltage regulator designed to provide a stable, adjustable DC output from higher-voltage input supplies. With up to 400 mA output current capability and a wide 3.3 V to 40 V input range, it is suited to low-power embedded and industrial power-conditioning designs.

Part Description

The LDQ44PURY is an adjustable LDO voltage regulator housed in a compact 2 mm × 2 mm, 6-lead DFN package. It supports output voltages adjustable from 1.2 V to 12 V, allowing one device to support a range of common logic, analog, and sensor supply rails.

Its low-dropout architecture helps maintain regulation when the input voltage is only slightly higher than the programmed output voltage. The device also features low quiescent current, which is useful in systems that spend significant time in standby or battery-powered operation.

Integrated protection and control functions include:

• Up to 400 mA regulated output current
• 3.3 V to 40 V input voltage range
• Adjustable 1.2 V to 12 V output voltage
• Enable-controlled shutdown mode
• Power-good output indication
• Short-circuit protection
• Thermal shutdown protection
• Output active-discharge function
• Compact DFN 2 × 2, 6-lead package

Applications

Potential applications for the LDQ44PURY include:

• Microcontroller and embedded-system power rails
• Industrial sensor supply regulation
• 24 V and 36 V industrial control systems
• Automotive auxiliary electronic modules
• PLC input/output modules
• Field transmitters and process-control equipment
• Battery-operated measurement instruments
• Communications and networking equipment
• Portable data-acquisition devices
• Low-noise analog and mixed-signal circuits
• Power supplies for small displays, sensors, and interface ICs

Industries

The LDQ44PURY can be used in several industries, including:

• Industrial automation
• Automotive electronics
• Energy and power-management systems
• Telecommunications
• Building automation
• Medical instrumentation
• Consumer electronics
• Test and measurement
• Internet of Things equipment
• Smart agriculture and environmental monitoring

Usage Ideas

1. 24 V Sensor Interface Supply
   Use the regulator to convert a 24 V industrial supply into a stable 3.3 V rail for a microcontroller, temperature sensor, and communication interface.

2. Automotive Auxiliary Power Rail
   Create a regulated 5 V or 3.3 V supply for a low-current automotive monitoring module operating from a higher-voltage vehicle electrical system.

3. Adjustable Laboratory Sensor Module
   Build a compact sensor-development board with an adjustable output rail between 1.2 V and 12 V, enabling testing of different analog sensors and low-power ICs.

Conclusion

The STMicroelectronics LDQ44PURY is a versatile 400 mA adjustable LDO regulator for designs requiring wide input-voltage tolerance, compact size, and integrated safety features. Its adjustable output, shutdown control, power-good indication, and protection functions make it a practical choice for reliable power rails in industrial, automotive, embedded, and battery-aware electronic systems.