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LDH40MR

LDH40MR

STMicroelectronics
Linear Voltage Regulator IC Positive Adjustable 1 Output 200mA SOT-23-5
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Overview

The LDH40MR is a high-voltage, low-quiescent-current linear regulator designed to operate from an input up to 40V. It provides a stable adjustable output between 1.2V and 22V with a maximum output current of 200mA, making it suitable for automotive and industrial battery-powered systems. The device features an ultra-low standby current of 0.3 uA and integrated safety functions including thermal shutdown and current limiting.

Why Choose This Part

This regulator offers an excellent Power Supply Rejection Ratio (PSRR) of 70dB at 1kHz, ensuring clean power for sensitive analog stages. It combines high voltage tolerance (40V) with a very low typical quiescent current of 50 uA, while the SOT-23-5L package provides a compact footprint for space-constrained designs.

Applications

Automotive Always-On Systems
Ideal for powering microcontrollers and sensors directly from a 12V or 24V vehicle battery where low standby current is critical to prevent battery drain.
Industrial Sensor Nodes
Regulates 24V industrial rails down to low-voltage logic levels for smart sensors and field transmitters.
Battery-Powered Tools
Provides efficient power conversion for multi-cell Li-ion packs with high voltage peaks during charging or load switching.

Key Specifications

PSRR 70dB ~ 65dB (1kHz)
Output Type Adjustable
Mounting Type Surface Mount
Package / Case SC-74A, SOT-753
Control Features Current Limit, Enable, Power Good
Current - Output 200mA
Protection Features Over Current, Over Temperature, Short Circuit, Under Voltage Lockout (UVLO)
Number of Regulators 1
Output Configuration Positive
Operating Temperature -40degC ~ 150degC (TJ)
Voltage - Input (Max) 40V
Voltage Dropout (Max) 1V @ 200mA
Current - Supply (Max) 500 uA
Voltage - Output (Max) 22V
Supplier Device Package SOT-23-5
Voltage - Output (Min/Fixed) 1.2V

Getting Started

To use the LDH40MR, connect a 1uF ceramic capacitor to both the input and output pins for stability. Set the desired output voltage using a resistor divider at the ADJ pin, and utilize the EN pin to transition the device into its 0.3 uA standby mode when the system is inactive.