Texas Instruments LP3875EMP-1.8/NOPB

Overview

LP3875EMP-1.8/NOPB from Texas Instruments is a 1.5-A ultra-low-dropout linear regulator in TO-263 (DDPAK) package, delivering fixed 1.8 V output with ±1.5% accuracy at room temperature, 380 mV dropout at 1.5 A, and 10 nA shutdown current - designed for microprocessor core power in space-constrained embedded systems.

For engineers reviewing the LP3875EMP-1.8/NOPB datasheet, LP3875EMP-1.8/NOPB pinout, LP3875EMP-1.8/NOPB application, or LP3875EMP-1.8/NOPB equivalent, key selection criteria include remote-sense capability, thermal performance in TO-263, load regulation under 0.12%, and compatibility with low-ESR tantalum output capacitors.

Technical Context

The LP3875EMP-1.8/NOPB uses a PMOS pass element on a CMOS process to achieve input-to-output differential as low as 380 mV at full 1.5-A load while maintaining stability with 10 µF output capacitance. Its dedicated SENSE pin enables remote voltage regulation by closing the feedback loop at the load point, distinguishing it from the LP3872 which regulates only at the OUT pin.

It integrates overtemperature and overcurrent protection with thermal shutdown, supports shutdown via logic-low SD pin (10-nA quiescent), and features an open-drain ERROR flag that asserts low when output drops >10% below nominal - active only in normal mode, disabled during shutdown.

Key Specifications

Pinout & Package

LP3875EMP-1.8/NOPB is housed in a 5-pin DDPAK/TO-263 (KTT) package with exposed thermal pad (10.16 mm × 8.42 mm), optimized for high-power dissipation in compact PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPL7407LDR and TPS7A4701RGWR, LP3875EMP-1.8/NOPB uniquely delivers 1.5-A current with remote SENSE capability in TO-263, making it the only option among the three qualified for high-current, precision point-of-load regulation in space-constrained industrial controllers.

Availability

LP3875EMP-1.8/NOPB is available at Aetrix Electronics and suitable for microprocessor core supplies, GTL bus terminators, post-regulators, battery-powered DSP systems, and industrial embedded controllers requiring stable component supply with long-term lifecycle support.

Supply support for LP3875EMP-1.8/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, designing and manufacturing analog ICs, embedded processors, and system-on-chip solutions for industrial, automotive, and communications markets.

The LP387x product line was developed to address ultra-low-dropout, high-current linear regulation needs in battery-powered and thermally constrained applications - emphasizing CMOS-based efficiency, fast transient response, and robust protection features.

FAQ

What is the minimum input voltage required for stable operation of LP3875EMP-1.8/NOPB?

The minimum input voltage for LP3875EMP-1.8/NOPB is determined by its dropout specification: 380 mV typical at 1.5 A. Therefore, stable 1.8-V output requires VIN ≥ 2.18 V. The datasheet also specifies an absolute minimum VIN of 2.5 V under recommended operating conditions, meaning LP3875EMP-1.8/NOPB operates reliably from 2.5 V to 7 V - ensuring margin against line sag and thermal derating. This range supports single-cell Li-ion (2.7–4.2 V) and post-regulated 2.5-V supplies.

Can LP3875EMP-1.8/NOPB be used without connecting the SENSE pin?

Yes, LP3875EMP-1.8/NOPB can operate without the SENSE pin connected - but only if remote load regulation is not required. In that case, the SENSE pin must be tied directly to the OUT pin to maintain internal feedback loop integrity. Leaving SENSE floating will cause regulation failure. When connected to OUT, LP3875EMP-1.8/NOPB behaves like a standard LDO regulating at the OUT pin, with load regulation specified at 0.06% typical. The SENSE function is optional and exclusively for improving regulation at physically distant loads.

Does LP3875EMP-1.8/NOPB include reverse current protection?

LP3875EMP-1.8/NOPB does not include active reverse current protection. Its internal PMOS pass transistor has an inherent body diode that becomes forward-biased if the output voltage exceeds the input voltage - allowing up to 200 mA continuous or 1 A peak reverse current. This behavior is documented in the datasheet's "Reverse Current Path" section. System-level reverse current blocking requires an external Schottky diode or ideal diode controller; the device itself relies on proper system architecture to avoid VOUT > VIN conditions.

What output capacitor types are validated for stable operation with LP3875EMP-1.8/NOPB?

Tantalum capacitors are explicitly recommended for LP3875EMP-1.8/NOPB output stabilization, with 10 µF minimum capacitance and ESR between 0.1 Ω and 4 Ω. Ceramic capacitors are acceptable if X7R/X5R dielectric is used (to avoid voltage/temperature drift), but require careful ESR consideration due to their near-zero impedance. Aluminum electrolytics are discouraged due to high and temperature-sensitive ESR - especially below 0°C - which risks instability. All capacitors must be placed within 1 cm of the OUT and GND pins using dedicated low-impedance traces.

How does the ERROR flag on LP3875EMP-1.8/NOPB behave during shutdown?

The ERROR flag on LP3875EMP-1.8/NOPB is intentionally disabled during shutdown mode: when the SD pin is pulled low, the ERROR output becomes invalid (high-impedance) to minimize power consumption. It only functions in active mode, asserting low when the regulated output falls >10% below 1.8 V (i.e., <1.62 V) due to input undervoltage, thermal foldback, or current limit. The flag includes 5% hysteresis to prevent chatter and requires an external 10-kΩ pullup resistor to operate correctly - a direct ground connection disables the function entirely.