Texas Instruments LP2951DRG4

Overview

LP2951DRG4 from Texas Instruments is a 100mA, wide-input (2V–30V), low-dropout adjustable/fixed voltage regulator in an 8-pin WSON package. It delivers ±1% output accuracy over line/load/temperature, features 340mV typical dropout at 100mA, 50μA quiescent current, and integrated shutdown control and error flag for power sequencing in industrial power rails.

For engineers reviewing the LP2951DRG4 datasheet, LP2951DRG4 pinout, LP2951DRG4 application, or LP2951DRG4 equivalent, this page provides verified electrical specs, thermal performance data, fixed/adjustable configuration guidance, and real-world use cases in grid infrastructure and motor drive systems.

Technical Context

The LP2951DRG4 implements a precision bandgap reference (1.20V typ) with error amplifier feedback to regulate output either as fixed (3.3V/5.0V) or adjustable (1.235V–29V). Its active-low open-drain ERROR pin monitors V_FB with ±6% nominal output deviation detection, enabling system-level fault signaling and supply sequencing.

Shutdown is active-high with 0.7V logic threshold; internal current limiting and thermal shutdown protect against overload and junction overheating. The device supports ceramic output capacitors from 1μF to 100μF with ESR up to 2Ω, eliminating need for tantalum or electrolytic types.

Key Specifications

Pinout & Package

LP2951DRG4 uses an 8-pin WSON (DRG) package measuring 3.0mm × 3.0mm with exposed thermal pad. Pin 1 is marked by a dot; pin numbering follows standard top-view counterclockwise layout.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV70733PDQNR and TPS7A1633DRBR, the LP2951DRG4 uniquely combines 30V input tolerance, ERROR flag, shutdown control, and ±1% accuracy in a cost-optimized WSON package-making it ideal for industrial power sequencing where fault visibility and wide VIN are mandatory.

Availability

LP2951DRG4 is available at Aetrix Electronics and suitable for grid infrastructure monitoring, factory automation I/O modules, and motor drive control boards requiring stable component supply across extended temperature and voltage ranges.

Supply support for LP2951DRG4 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

Texas Instruments is a global semiconductor leader delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and communications markets.

The LP295x family was designed specifically for industrial power management applications requiring wide-input LDOs with integrated supervision and sequencing capability-targeting grid, motor control, and building automation systems.

FAQ

What output voltage options does the LP2951DRG4 support?

The LP2951DRG4 supports both fixed and adjustable output configurations. In fixed mode (FEEDBACK tied to VTAP, OUTPUT tied to SENSE), it delivers 3.3V or 5.0V. In adjustable mode (FEEDBACK connected to external resistor divider, SENSE and VTAP floating), output is set from 1.235V to 29V using the internal 1.20V reference. The LP2951DRG4 datasheet specifies ±1% accuracy across this full range under load, line, and temperature variation.

How does the ERROR pin function on the LP2951DRG4?

The ERROR pin on the LP2951DRG4 is an active-low open-drain output that asserts low when the regulated output drops more than 6% below its nominal value. It monitors the FEEDBACK pin voltage relative to the internal reference and provides system-level fault signaling-commonly used to trigger MCU interrupts or disable downstream circuitry. The LP2951DRG4 ERROR pin sinks up to 400μA with a typical VOL of 250mV at 25°C, enabling direct connection to 3.3V or 5V logic without pull-up resistors.

Can the LP2951DRG4 operate with ceramic output capacitors?

Yes, the LP2951DRG4 is fully stable with ceramic output capacitors ranging from 1μF to 100μF and ESR values from 0Ω to 2Ω-eliminating reliance on higher-ESR tantalum or aluminum electrolytic types. This ceramic compatibility reduces board area, improves reliability, and enhances transient response. The LP2951DRG4 datasheet confirms stability across this range without requiring series resistance or feed-forward capacitors in most configurations.

What is the thermal performance of the LP2951DRG4 in its DRG package?

The LP2951DRG4 in the 3.0mm × 3.0mm WSON (DRG) package has a junction-to-board thermal resistance (R_θJB) of 31.0°C/W and junction-to-ambient (R_θJA) of 61.7°C/W under JEDEC JESD51-7 high-K board conditions. With its exposed thermal pad soldered to a 1-in² copper pour, the LP2951DRG4 sustains 100mA continuous output at 125°C ambient when VIN–VOUT ≤ 1.5V. Derating curves in the LP2951DRG4 datasheet confirm safe operation up to 125°C junction temperature under specified load and airflow conditions.

Does the LP2951DRG4 support power supply sequencing in multi-rail systems?

Yes, the LP2951DRG4 supports robust power supply sequencing via its SHUTDOWN and ERROR pins. The active-high SHUTDOWN pin enables precise turn-on/turn-off timing control, while the ERROR pin provides early fault detection to halt upstream regulators or initiate system reset. Used together, these pins allow cascaded start-up (e.g., 5V rail enabled first, then 3.3V after ERROR confirms 5V stability) and graceful shutdown-key for FPGA, DSP, and multi-core MCU applications. The LP2951DRG4 timing specifications include tPGDH (40μs) and tPGDL (10μs) for predictable power-good assertion/deassertion.