Texas Instruments LP3872EMP-5.0/NOPB

Overview

LP3872EMP-5.0/NOPB from Texas Instruments is a 1.5-A ultra-low-dropout linear regulator in SOT-223 package, delivering fixed 5.0 V output with ±1.5% accuracy at room temperature, 380 mV dropout at 1.5 A load, and 10 nA shutdown quiescent current. It serves as a primary power supply for low-voltage microprocessors and GTL/SSTL bus terminators where fast transient response and minimal input-output differential are critical.

For engineers reviewing the LP3872EMP-5.0/NOPB datasheet, LP3872EMP-5.0/NOPB pinout, LP3872EMP-5.0/NOPB application, or LP3872EMP-5.0/NOPB equivalent, key selection criteria include verified 5.0 V output stability under 1.5-A DC load, ERROR flag functionality (active-low at 10% VOUT drop), thermal performance in SOT-223 (RθJA = 65.2°C/W), and compatibility with 10 µF tantalum output capacitors.

Technical Context

The LP3872EMP-5.0/NOPB uses a CMOS-based PMOS pass element enabling ultra-low dropout operation independent of load current. Its internal error amplifier drives the gate of the PMOS transistor to maintain regulation, with feedback taken directly from the OUT pin (no SENSE capability-exclusive to LP3875).

It integrates an open-drain ERROR flag comparator with 10% VOUT threshold and 5% hysteresis, and a CMOS-compatible shutdown input requiring external 10-kΩ pullup. Thermal shutdown and short-circuit protection operate autonomously without external components.

Key Specifications

Pinout & Package

SOT-223 (5-pin) package: 6.50 mm × 3.56 mm body size, exposed thermal pad on bottom (pin 3 = GND), compatible with standard reflow profiles and manual soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TSS721AIDR, LP3872EMP-5.0/NOPB offers lower dropout and integrated fault signaling; versus TPS7A4701RGWR, it delivers higher current and fixed 5.0 V without external components-but lacks soft-start and has higher noise.

Availability

LP3872EMP-5.0/NOPB is available at Aetrix Electronics and suitable for microprocessor power supplies, GTL/SSTL bus terminators, and battery-powered instrumentation requiring stable component supply, long-lifecycle support, and guaranteed traceable sourcing.

Supply support for LP3872EMP-5.0/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 headquartered in Dallas, Texas, specializing in analog, embedded processing, and power management technologies since 1930.

The LP387x series was designed specifically for high-current, low-dropout applications in microprocessor, DSP, and bus-termination systems where fast transient response and ultra-low quiescent current in shutdown mode are essential.

FAQ

What is the minimum input voltage required for LP3872EMP-5.0/NOPB to regulate 5.0 V output?

The minimum input voltage is the sum of the nominal output voltage and the dropout voltage at the intended load. For LP3872EMP-5.0/NOPB delivering 1.5 A, dropout is 380 mV, so minimum VIN = 5.0 V + 0.38 V = 5.38 V. However, the absolute minimum specified VIN is 2.5 V-so regulation is only guaranteed above 5.38 V at full load. At lighter loads, e.g., 150 mA, dropout drops to 38 mV, allowing regulation from 5.038 V.

Does LP3872EMP-5.0/NOPB support remote voltage sensing like the LP3875?

No. LP3872EMP-5.0/NOPB does not include a SENSE pin or remote-sense capability. Its feedback is taken solely at the OUT pin. The SENSE function is exclusive to the LP3875 variant. Using LP3872EMP-5.0/NOPB for remote loads introduces voltage drop across PCB traces-e.g., 150 mΩ trace resistance causes 225 mV drop at 1.5 A, degrading regulation accuracy at the load point.

How should the ERROR pin of LP3872EMP-5.0/NOPB be connected in a typical application?

The ERROR pin of LP3872EMP-5.0/NOPB is an open-drain output and must be pulled high with a 10-kΩ resistor to VIN or another stable supply. It asserts low when output voltage falls ≥10% below 5.0 V (i.e., ≤4.5 V). If unused, connect ERROR directly to GND per TI recommendation-leaving it floating may cause undefined behavior or increased leakage current.

Can LP3872EMP-5.0/NOPB be used with ceramic output capacitors?

Yes, but with caution. LP3872EMP-5.0/NOPB is stable with ceramic capacitors ≥10 µF, provided ESR is within 100 mΩ to 4 Ω. X7R or X5R dielectrics are recommended due to stable capacitance vs. voltage/temperature. Avoid Z5U/Y5V ceramics, which can lose >60% capacitance at half-rated voltage-potentially causing instability under load transients.

What thermal considerations apply to LP3872EMP-5.0/NOPB in SOT-223 package?

In SOT-223, LP3872EMP-5.0/NOPB has RθJA = 65.2°C/W. At 1.5 A with 5.38 V input and 5.0 V output, power dissipation is (5.38 − 5.0) × 1.5 = 0.57 W. Junction temperature rise = 0.57 × 65.2 ≈ 37°C. With 60°C ambient, TJ ≈ 97°C-within the −40°C to 125°C limit. Adding 1-in² 2-oz copper pour under the thermal pad reduces RθJA significantly and is strongly advised for continuous 1.5-A operation.