STMicroelectronics LDK715M50R

Overview

LDK715M50R from STMicroelectronics is a high-input-voltage, ultra-low-quiescent-current LDO linear regulator delivering 5.0 V at up to 85 mA output current with 500 mV typical dropout at full load, 5 µA typical quiescent current, and stable operation with 0.47–10 µF ceramic output capacitors - used in battery-powered industrial sensors and mobile phone power rails.

For engineers reviewing the LDK715M50R datasheet, LDK715M50R pinout, LDK715M50R application, or LDK715M50R equivalent, key selection criteria include input voltage range (4.3–24 V), thermal performance (R_thJA = 195 °C/W for SOT23-5L), output accuracy (±2% over –40 to 125 °C), and compatibility with low-ESR ceramic capacitors without external compensation.

Technical Context

The LDK715M50R integrates a bandgap reference, current-limit protection, and thermal shutdown within a single-stage LDO architecture. Its internal constant-current limit (~120 mA short-circuit current) and junction temperature monitoring ensure safe operation under overload and ambient extremes.

It operates across –40 °C to +125 °C junction temperature with guaranteed stability using ceramic output capacitors as low as 0.47 µF, eliminating need for tantalum or aluminum electrolytics. The device requires no external compensation and supports fast load transients (5 µs rise/fall) with <0.7 ms turn-on time.

Key Specifications

Pinout & Package

LDK715M50R is packaged in SOT23-5L - a surface-mount, 5-pin plastic package with exposed thermal pad (not electrically connected), footprint compatible with standard pick-and-place equipment and reflow profiles.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with TLV70750DBVR and MCP1703T-5002E/MB, the LDK715M50R uniquely combines 24 V input capability, 5 µA IQ, integrated current limiting, and ceramic-capacitor stability - making it the only option qualified for harsh-environment, wide-input, ultra-low-power industrial LDO use cases.

Availability

LDK715M50R is available at Aetrix Electronics and suitable for industrial sensor nodes, battery-powered data loggers, smart meter auxiliary supplies, and mobile phone power rails requiring stable component supply across extended temperature and long product lifecycles.

Supply support for LDK715M50R includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets since 1987.

The LDK715 series belongs to ST's high-voltage, ultra-low-I_Q LDO portfolio, engineered specifically for battery longevity and robustness in industrial and portable equipment where input voltage varies widely and standby power is critical.

FAQ

What is the minimum input voltage required for LDK715M50R to regulate 5.0 V output?

The LDK715M50R requires a minimum input voltage of 4.3 V to maintain regulation at 5.0 V output. Below this, dropout behavior begins - output voltage drops linearly with input. At 85 mA load, the typical dropout is 500 mV, so 5.5 V input is recommended for reliable full-load operation.

Can LDK715M50R operate with a 0.47 µF ceramic output capacitor?

Yes - the LDK715M50R is explicitly characterized and guaranteed stable with ceramic output capacitors ranging from 0.47 µF to 10 µF, including X5R and X7R dielectrics. No series resistor or ESR tuning is needed, unlike many legacy LDOs.

Does LDK715M50R include an enable pin or power-good indicator?

No - the LDK715M50R has no enable (EN) pin or power-good (PG) output. It is a fixed-output, always-on LDO. For controlled start-up sequencing, external MOSFET gating or system-level enable logic must be implemented upstream of the IN pin.

How does thermal performance differ between SOT23-5L and DFN8 3x3 packages?

The SOT23-5L package has R_thJA = 195 °C/W, limiting continuous 85 mA operation to ≤40 °C ambient without PCB copper pour. The DFN8 3x3 package offers R_thJA = 52 °C/W - enabling full 85 mA output up to 100 °C ambient when using standard 2-layer PCB with thermal vias to inner ground planes.