Texas Instruments LP3874EMPX-1.8/NOPB

Overview

LP3874EMPX-1.8/NOPB from Texas Instruments is a 0.8-A ultra-low-dropout linear regulator in DDPAK/TO-263-5 package, delivering fixed 1.8 V output with ±1.5% accuracy at room temperature, 240 mV dropout at full load, and 10 nA shutdown quiescent current-designed for microprocessor core power in space-constrained industrial and battery-powered systems.

For engineers reviewing the LP3874EMPX-1.8/NOPB datasheet, LP3874EMPX-1.8/NOPB pinout, LP3874EMPX-1.8/NOPB application, or LP3874EMPX-1.8/NOPB equivalent, key selection criteria include remote-sense capability (SENSE pin), thermal performance (R_θJA = 40.3°C/W), error flag monitoring, and compatibility with low-ESR tantalum output capacitors.

Technical Context

The LP3874EMPX-1.8/NOPB uses a CMOS-based PMOS pass transistor architecture enabling ultra-low dropout and load-independent quiescent current. Its integrated SENSE pin provides remote voltage feedback to compensate for PCB trace resistance, improving regulation at the point of load by up to 80 mV under 0.8-A conditions.

It features active overtemperature and overcurrent protection with thermal shutdown, open-drain ERROR flag with 10% output undervoltage threshold and 5% hysteresis, and CMOS-compatible shutdown input requiring external 10-kΩ pullup. The device operates across −40°C to +125°C junction temperature with 2.5 V to 7 V input range.

Key Specifications

Pinout & Package

LP3874EMPX-1.8/NOPB is housed in a thermally enhanced 5-pin DDPAK/TO-263 package (10.16 mm × 8.42 mm), with exposed thermal pad soldered to PCB for optimal heat dissipation (R_θJC(bot) = 1°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and MCP1703T-1802E/MB, LP3874EMPX-1.8/NOPB uniquely balances 0.8-A capability, SENSE-enabled point-of-load accuracy, and 10-nA shutdown-making it optimal for space-constrained, battery-aware digital core regulation where both performance and power efficiency are critical.

Availability

LP3874EMPX-1.8/NOPB is available at Aetrix Electronics and suitable for microprocessor core supplies, GTL+ bus terminators, SCSI termination circuits, and battery-powered instrumentation requiring stable component supply with long-term manufacturability.

Supply support for LP3874EMPX-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 specializing in analog and embedded processing technologies, with leadership in power management ICs for industrial, automotive, and consumer applications.

The LP387x series was designed specifically for high-current, ultra-low-dropout regulation in space- and power-constrained digital systems-emphasizing fast transient response, remote sensing, and robust thermal performance in surface-mount packages.

FAQ

What is the minimum input voltage required for LP3874EMPX-1.8/NOPB to regulate 1.8 V output?

The minimum input voltage is determined by dropout: at 0.8 A, LP3874EMPX-1.8/NOPB requires VIN ≥ 2.04 V (1.8 V + 240 mV). However, per datasheet Section 6.3, the absolute minimum operating VIN is 2.5 V-so LP3874EMPX-1.8/NOPB must be supplied with ≥2.5 V to ensure guaranteed regulation across all conditions, including temperature and line variation.

Can LP3874EMPX-1.8/NOPB be used without connecting the SENSE pin?

Yes-LP3874EMPX-1.8/NOPB functions as a standard LDO when SENSE is tied directly to OUT. This configuration regulates voltage at the OUT pin rather than at the remote load, accepting the IR drop across PCB traces. The SENSE pin is optional and only required when regulation at the point-of-load is critical, such as for FPGA or DDR memory VDDQ rails.

How does the ERROR flag on LP3874EMPX-1.8/NOPB behave during shutdown?

When the SD pin is pulled low to activate shutdown mode, the ERROR flag on LP3874EMPX-1.8/NOPB becomes invalid and is disabled to conserve power. The ERROR pin is only active during normal operation; it asserts low when VOUT falls >10% below 1.8 V due to input undervoltage, overload, or thermal limit-providing actionable fault indication before shutdown occurs.

What output capacitor types are recommended for stable operation of LP3874EMPX-1.8/NOPB?

Tantalum capacitors are explicitly recommended for LP3874EMPX-1.8/NOPB output stabilization due to their ideal ESR range (100 mΩ to 4 Ω) and stable temperature performance. Ceramic capacitors may be used if X7R/X5R dielectric is selected and ESR remains within the stable region shown in Figure 13-but require careful voltage derating to avoid capacitance collapse. Aluminum electrolytics are discouraged unless impedance is specified at ≥20 kHz.

Does LP3874EMPX-1.8/NOPB include reverse current protection?

No-LP3874EMPX-1.8/NOPB lacks integrated reverse current protection. Its internal PMOS pass transistor includes a parasitic body diode that conducts from OUT to IN if VOUT exceeds VIN. This path supports up to 200 mA continuous or 1 A peak current. For bidirectional isolation, an external Schottky diode in series with IN or a dedicated OR-ing controller is required.