STMicroelectronics LD2980ABM50TR

Overview

LD2980ABM50TR from STMicroelectronics is a 5.0 V fixed-output ultra-low-dropout linear voltage regulator in SOT23-5L package, delivering up to 50 mA with 120 mV typical dropout at full load, 80 µA quiescent current in active mode, and <1 µA shutdown current - designed for low-noise, battery-powered systems requiring stable local regulation with logic-controlled enable.

For engineers reviewing the LD2980ABM50TR datasheet, LD2980ABM50TR pinout, LD2980ABM50TR application, or LD2980ABM50TR equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, application-specific use cases, and confirmed alternative options for 5 V LDO selection in space-constrained, low-power embedded systems.

Technical Context

The LD2980ABM50TR uses a PNP pass transistor architecture enabling ultra-low dropout (7 mV typ. at 1 mA, 120 mV typ. at 50 mA) and stable operation with low-ESR ceramic capacitors ≥2.2 µF. Its inhibit-controlled shutdown function responds to TTL-compatible logic levels on Pin 3 (INHIBIT), with defined VIH ≥1.3 V and VIL ≤0.18 V across –40 to 125 °C.

It integrates internal current limiting, thermal shutdown at 170 °C, and delivers 160 µVRMS output noise (300 Hz–50 kHz) with 63 dB supply voltage rejection at 1 kHz. Output voltage tolerance is ±0.5% (A version), verified over full temperature and load range (2.925–3.075 V for 3.0 V variants; 4.875–5.125 V for 5.0 V variants).

Key Specifications

Pinout & Package

SOT23-5L: 5-pin surface-mount package (2.95 × 1.60 mm footprint, 1.30 mm max height), optimized for high-density PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 5 V LDO applications.

Compared with AP2112K-5.0 and MCP1700T-5002E, the LD2980ABM50TR uniquely balances ultra-low dropout (120 mV), tight output tolerance (±0.5%), and logic-controlled shutdown - making it optimal for battery-powered systems needing both precision regulation and intelligent power management.

Availability

LD2980ABM50TR is available at Aetrix Electronics and suitable for portable medical sensors, industrial IoT edge nodes, wearable audio devices, and automotive body control modules requiring stable component supply with guaranteed long-term manufacturability.

Supply support for LD2980ABM50TR 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 microcontrollers, power management ICs, sensors, and analog chips for industrial, automotive, and consumer markets.

The LD2980 series belongs to ST's ultra-low-dropout linear regulator product line, engineered specifically for space-constrained, battery-operated applications demanding low noise, low quiescent current, and robust thermal performance across extended temperature ranges.

FAQ

What is the minimum input voltage required for regulation at 5.0 V output?

The LD2980ABM50TR maintains regulation when input voltage exceeds output voltage by its dropout voltage. At 50 mA load and 25 °C, typical dropout is 120 mV, so minimum input is ~5.12 V. Over temperature (–40 to 125 °C), max dropout reaches 225 mV, requiring ≥5.225 V input for guaranteed regulation at full load and extreme temperatures.

Can the INHIBIT pin be left unconnected?

No - the INHIBIT pin is not internally pulled up or down. Leaving it floating risks undefined output state and potential instability. If shutdown control is unused, tie INHIBIT directly to VIN to maintain continuous operation; if used, drive it with a clean logic signal meeting VIH ≥1.3 V and VIL ≤0.18 V across temperature.

Which output capacitor types and values are validated for stability?

ST validates stability with ≥2.2 µF X7R or C0G ceramic capacitors (ESR < 100 mΩ at 100 kHz). For 5.0 V versions, 2.2 µF is the minimum recommended value. Tantalum capacitors may work but are not characterized for stability; aluminum electrolytics are incompatible due to ESR and aging effects.

Does the LD2980ABM50TR provide reverse current protection?

Yes - the internal PNP pass transistor lacks a body diode, preventing reverse current flow from VOUT to VIN when output voltage exceeds input. However, a small reverse current (~160 µA) flows through internal feedback resistors to GND if VOUT is forced above VIN; external reverse-blocking diodes are unnecessary in most designs.