Texas Instruments LP3872ES-2.5/NOPB

Overview

LP3872ES-2.5/NOPB from Texas Instruments is a 2.5-V fixed-output, 1.5-A ultra-low-dropout linear regulator in TO-263 (DDPAK) package, featuring 380 mV dropout at full load, ±1.5% output voltage accuracy at 25°C, and 10-nA shutdown quiescent current. It delivers stable power to low-voltage microprocessors and GTL/SSTL bus terminators where fast transient response and minimal input–output differential are critical.

For engineers reviewing the LP3872ES-2.5/NOPB datasheet, LP3872ES-2.5/NOPB pinout, LP3872ES-2.5/NOPB application, or LP3872ES-2.5/NOPB equivalent, key selection considerations include dropout performance at 1.5 A, ERROR flag behavior for undervoltage detection, thermal resistance (R_θJA = 40.3°C/W in TO-263), remote-sense absence (LP3872 vs. LP3875), and CMOS-based ground current independence from load.

Technical Context

The LP3872ES-2.5/NOPB uses a PMOS pass transistor architecture enabling ultra-low dropout and eliminating reverse-current protection diodes. Its error amplifier and reference circuit operate from the input rail, allowing regulation down to VIN = VOUT + V_DROPOUT, with minimum input voltage clamped at 2.5 V.

It integrates an open-drain ERROR flag that asserts low when output drops ≥10% below nominal (2.5 V), with 5% hysteresis, and a dedicated SD pin requiring external 10-kΩ pullup for reliable shutdown activation. No SENSE pin is present-voltage regulation is referenced solely to the OUT pin.

Key Specifications

Pinout & Package

LP3872ES-2.5/NOPB is housed in a 5-pin DDPAK/TO-263 (KTT) package with exposed thermal pad, measuring 10.16 mm × 8.42 mm. The package supports high-power dissipation via low R_θJC (1°C/W bottom) and requires PCB copper area for thermal management.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TSS721AIDR, LP3872ES-2.5/NOPB offers lower dropout and integrated fault signaling; versus TPS7A4701RGWR, it delivers higher current and simpler fixed-output implementation but lacks adjustability and soft-start-making it optimal for cost-sensitive, high-current 2.5-V point-of-load regulation.

Availability

LP3872ES-2.5/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 LP3872ES-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 processing technologies, with leadership in power management ICs since the 1980s.

The LP387x series was designed specifically for high-current, low-voltage applications demanding ultra-low dropout, fast transient response, and robust protection-targeting microprocessor cores, memory interfaces, and portable electronics.

FAQ

What is the minimum input voltage required for LP3872ES-2.5/NOPB to regulate 2.5 V at 1.5 A?

The minimum input voltage is defined by dropout: V_IN(MIN) = V_OUT + V_DROPOUT. At 1.5 A, typical dropout is 380 mV, so V_IN(MIN) = 2.5 V + 0.38 V = 2.88 V. Per datasheet Section 6.3, the absolute minimum VIN is also specified as 2.5 V-thus 2.88 V governs full-load operation. LP3872ES-2.5/NOPB will not sustain regulation below this level.

Does LP3872ES-2.5/NOPB support remote voltage sensing like LP3875?

No. LP3872ES-2.5/NOPB has no SENSE pin and regulates voltage only at the OUT pin. Voltage drop across PCB traces to the load is uncorrected. In contrast, LP3875 includes a dedicated SENSE pin to improve regulation at the remote load point. This functional distinction is explicitly stated in the datasheet's Pin Functions table and Feature Description section. LP3872ES-2.5/NOPB must be placed close to the load or used with low-impedance routing.

How does the ERROR flag on LP3872ES-2.5/NOPB behave during shutdown?

When the SD pin is pulled low to activate shutdown mode, the ERROR flag is forced invalid (high-impedance) to conserve power. It does not reflect output voltage status during shutdown. The ERROR pin only becomes active when SD is high and the device is in normal operation. This behavior is documented in Section 7.4.3 ("ERROR Flag Operation") and Figure 11 of the LP3872ES-2.5/NOPB datasheet.

What is the recommended pullup resistor value for the ERROR pin of LP3872ES-2.5/NOPB?

Texas Instruments recommends a 10-kΩ to 1-MΩ pullup resistor on the ERROR pin. A 10-kΩ value ensures fast flag response and noise immunity while limiting current draw to ~250 µA when asserted low (at 2.5 V). Higher values reduce power but increase susceptibility to noise and slow rise time. The datasheet states this explicitly in Section 7.4.3 and Figure 12 (Typical Application Circuit). LP3872ES-2.5/NOPB's ERROR sink capability is rated for 1 mA maximum.

Can LP3872ES-2.5/NOPB be used with ceramic output capacitors?

Yes-LP3872ES-2.5/NOPB is stable with ceramic output capacitors ≥10 µF, provided ESR remains within the 100 mΩ to 4 Ω range shown in Figure 14. X7R or X5R dielectrics are strongly recommended to maintain capacitance across voltage and temperature. Z5U/Y5V types are discouraged due to severe capacitance loss (>60%) at rated voltage. The device's stability criteria are verified per Section 8.2.2.2 and Figure 14 of the LP3872ES-2.5/NOPB datasheet.