Texas Instruments LP3872ESX-2.5/NOPB

Overview

LP3872ESX-2.5/NOPB from Texas Instruments is a 1.5-A ultra-low-dropout linear regulator with fixed 2.5-V output, CMOS-based architecture, 380-mV dropout at full load, ±1.5% output voltage accuracy, and integrated ERROR flag for undervoltage detection-designed for microprocessor core power in space-constrained portable systems.

For engineers reviewing the LP3872ESX-2.5/NOPB datasheet, LP3872ESX-2.5/NOPB pinout, LP3872ESX-2.5/NOPB application, or LP3872ESX-2.5/NOPB equivalent, key selection factors include guaranteed 1.5-A DC output under 2.5–7-V input, 10-nA shutdown quiescent current, SOT-223 thermal performance (R_θJA = 65.2°C/W), and ERROR flag threshold at −10% V_OUT with hysteresis.

Technical Context

The LP3872ESX-2.5/NOPB uses a PMOS pass element enabling ultra-low dropout operation independent of load current, with internal CMOS biasing ensuring stable 10-nA shutdown current across temperature. Its ERROR flag is an open-drain output that asserts low when regulated output falls >10% below nominal, featuring 5% hysteresis and reset delay <1 µs.

Unlike the LP3875, this device lacks a SENSE pin and regulates voltage solely at the OUT pin-not remotely-making it suitable for local regulation where trace resistance is negligible. It supports fast transient response due to high loop bandwidth enabled by low-output-capacitor requirements (≥10 µF tantalum, ESR 0.1–4 Ω).

Key Specifications

Pinout & Package

SOT-223 (5-pin) package: 6.50 mm × 3.56 mm body, exposed thermal pad on bottom, rated for 65.2°C/W junction-to-ambient thermal resistance under standard PCB layout.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-dropout linear regulator applications.

Compared with TSS721AIDR and TPS7A4700RGWR, the LP3872ESX-2.5/NOPB uniquely combines 1.5-A capability, 380-mV dropout, ±1.5% accuracy, and hardware ERROR signaling in a compact SOT-223 package-making it optimal for space- and reliability-critical 2.5-V microprocessor rails.

Availability

LP3872ESX-2.5/NOPB is available at Aetrix Electronics and suitable for microprocessor core supplies, GTL bus terminators, DSP power rails, and post-regulator applications requiring stable component supply, long-lifecycle support, and consistent parametric performance.

Supply support for LP3872ESX-2.5/NOPB 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, embedded processing, and digital signal technologies, with leadership in power management innovation since the 1950s.

The LP387x product line was engineered specifically for high-current, low-noise, ultra-low-dropout regulation in battery-powered and thermally constrained systems-emphasizing minimal quiescent current, fast transient response, and robust fault signaling.

FAQ

What is the minimum input voltage required for LP3872ESX-2.5/NOPB to maintain regulation?

The LP3872ESX-2.5/NOPB requires a minimum input voltage of 2.5 V per datasheet specification, but practical operation demands VIN ≥ V_OUT + V_DROPOUT. At 1.5-A load, dropout is 380 mV, so minimum functional VIN is 2.88 V. Below this, output voltage sags beyond ±1.5% tolerance, and the ERROR flag asserts low.

Does LP3872ESX-2.5/NOPB support remote voltage sensing?

No. The LP3872ESX-2.5/NOPB does not include a SENSE pin and regulates voltage only at the OUT pin. Remote sensing is exclusive to the LP3875 variant. For applications with significant PCB trace resistance between regulator and load, voltage at the load will drop by I_LOAD × R_TRACE, and no internal compensation corrects this.

What capacitor types and values are required for stable operation of LP3872ESX-2.5/NOPB?

LP3872ESX-2.5/NOPB requires a minimum 10-µF output capacitor with ESR between 0.1 Ω and 4 Ω-tantalum capacitors are recommended. Input capacitance must also be ≥10 µF. Ceramic capacitors may be used if X7R/X5R dielectric is selected to avoid voltage- and temperature-induced capacitance loss.

How does the ERROR flag on LP3872ESX-2.5/NOPB behave during shutdown?

When the SD pin is pulled low to activate shutdown mode, the ERROR flag on LP3872ESX-2.5/NOPB is forced invalid and ceases to reflect output voltage status. This is intentional power-saving behavior. The ERROR pin becomes functional again only after SD returns high and the device exits shutdown, typically within 25 µs turn-on delay.

Is LP3872ESX-2.5/NOPB protected against reverse current flow from OUT to IN?

Yes. The LP3872ESX-2.5/NOPB contains an inherent parasitic body diode in its PMOS pass transistor. If V_OUT exceeds V_IN, reverse current flows through this diode. The device tolerates up to 200 mA continuous and 1 A peak reverse current-exceeding this risks latch-up or thermal damage.