Texas Instruments LP2951ACMX-3.0

Overview

LP2951ACMX-3.0 from Texas Instruments is a micropower low-dropout (LDO) voltage regulator with fixed 3.0 V output, 100 mA rated output current, 75 µA typical quiescent current, and 380 mV typical dropout at full load-designed for battery-powered systems requiring stable, low-power regulation in space-constrained applications.

For engineers reviewing the LP2951ACMX-3.0 datasheet, LP2951ACMX-3.0 pinout, LP2951ACMX-3.0 application, or LP2951ACMX-3.0 equivalent, this page delivers verified functional identity, validated SOIC-8 package mapping, confirmed error flag and shutdown interface behavior, real-world stability requirements (2.2 µF low-ESR output capacitor), and precise parameter boundaries per TI SNVS764Q Rev Q.

Technical Context

The LP2951ACMX-3.0 integrates a precision 1.235 V bandgap reference, error amplifier, PNP pass transistor, and dedicated comparator circuitry to enable both regulated power delivery and output health monitoring. Its architecture supports dual operating modes: active regulation (SHUTDOWN pin < 0.7 V) and ultra-low-quiescent shutdown (<10 µA).

Unlike the LP2950 series, the LP2951ACMX-3.0 implements a dedicated SENSE pin for remote voltage sensing, VTAP for internal resistor divider access, and FEEDBACK input enabling programmable configurations-though the -3.0 variant is factory-trimmed to deliver 3.0 V ±0.5% at 25°C without external resistors.

Key Specifications

Pinout & Package

LP2951ACMX-3.0 is housed in an 8-pin SOIC (D) package measuring 4.90 mm × 3.91 mm, with exposed thermal pad connected internally to GND (Pin 4). The package supports standard reflow profiles and provides 117.7°C/W junction-to-ambient thermal resistance on JEDEC High-K board.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LP2951CMX-3.0 and TLV70730PDQNR, the LP2951ACMX-3.0 uniquely combines ±0.5% initial accuracy, integrated error detection, remote sensing, and logic shutdown in a single SOIC-8 device-making it the only option among the three that satisfies simultaneous requirements for precision, supervisory intelligence, and design flexibility in battery-critical systems.

Availability

LP2951ACMX-3.0 is available at Aetrix Electronics and suitable for portable medical sensors, industrial data loggers, smart utility meters, and automotive body control modules requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for LP2951ACMX-3.0 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 company specializing in analog and embedded processing technologies, with leadership in power management innovation since the 1980s.

The LP2951 series was designed specifically for micropower, low-dropout regulation in battery-operated equipment-emphasizing ultra-low IQ, tight DC accuracy, and integrated system supervision features like ERROR flag and shutdown control.

FAQ

What is the minimum input voltage required for LP2951ACMX-3.0 to regulate 3.0 V output?

The LP2951ACMX-3.0 requires a minimum input voltage of 2.3 V to start up and maintain regulation. However, to sustain 3.0 V output at 100 mA load, VIN must exceed 3.38 V due to its 380 mV typical dropout voltage. At light loads (100 µA), dropout drops to 50–80 mV, allowing regulation down to ~3.08 V input. This behavior is fully characterized in TI SNVS764Q Section 7.6.

Can LP2951ACMX-3.0 be used without connecting the SENSE pin?

Yes-LP2951ACMX-3.0 operates correctly with SENSE tied to OUT, which is the default configuration for local regulation. The SENSE pin is optional and only required when compensating for PCB trace resistance between the regulator and load. Leaving SENSE unconnected is not permitted; it must be either shorted to OUT or routed to the load's power rail per TI layout guidelines.

How does the ERROR pin function in LP2951ACMX-3.0, and what external circuitry is needed?

The ERROR pin is an open-collector output that pulls low when the regulated output falls >5% below nominal (i.e., <2.85 V). It sinks ≥400 µA and requires an external pull-up resistor (typically 10 kΩ to 3.3 V or 5 V) to generate a logic-high signal during normal operation. This pin is commonly used to drive a microcontroller interrupt or reset generator for brownout recovery.

Is LP2951ACMX-3.0 stable with ceramic output capacitors, and what value is recommended?

Yes-LP2951ACMX-3.0 is explicitly characterized for stability with low-ESR ceramic capacitors ranging from 10 mΩ to 6 Ω. For the 3.0 V version, TI specifies a minimum 2.2 µF X7R or X5R ceramic capacitor placed within 5 mm of the OUT and GND pins. Smaller values (e.g., 1 µF) may cause instability; larger values (e.g., 10 µF) are acceptable but offer diminishing returns.

What thermal derating applies to LP2951ACMX-3.0 in SOIC-8 package at 100 mA load?

In SOIC-8 (D) package, LP2951ACMX-3.0 has a junction-to-ambient thermal resistance (RθJA) of 117.7°C/W on JEDEC High-K board. At 100 mA load with 3.38 V input (380 mV dropout), power dissipation is 38 mW-resulting in ~4.5°C junction rise above ambient. Derating is negligible below 125°C ambient; full 100 mA output remains valid up to TJ = 125°C per datasheet Section 7.3.