Texas Instruments LP3879SD-1.2/NOPB

Overview

LP3879SD-1.2/NOPB from Texas Instruments is a micropower, low-noise, fixed-output 1.2 V linear voltage regulator delivering up to 800 mA with ±1% initial output accuracy, 18 µV_RMS broadband noise (100 Hz–100 kHz), and operation from 2.5 V to 6 V input. It uses a VIP PNP pass element, supports ceramic output capacitors ≥10 µF, and targets FPGA core power, ASIC supplies in notebooks, and medical instrumentation.

For engineers reviewing the LP3879SD-1.2/NOPB datasheet, LP3879SD-1.2/NOPB pinout, LP3879SD-1.2/NOPB application, or LP3879SD-1.2/NOPB equivalent, key selection criteria include its 1.2 V fixed output, WSON-8 package thermal performance (θ_J−A ≈ 40°C/W), remote sense capability for load regulation, <10 µA shutdown current, and stability with ultra-low-ESR ceramic capacitors.

Technical Context

The LP3879SD-1.2/NOPB employs a vertically integrated PNP (VIP) architecture enabling high peak current (1200 mA), low ground pin current (5.5 mA at 800 mA load), and excellent line regulation (0.007%/V typical). Its internal bandgap reference feeds a precision error amplifier that drives the PNP pass transistor, with the BYPASS pin connecting to a 10 nF capacitor to reduce noise and stabilize loop dynamics.

Remote SENSE functionality allows direct feedback from the load point, improving load regulation under varying PCB trace impedance. The SHUTDOWN pin enables active control with 1.4 V turn-on threshold and <1 µA leakage, while over-temperature and over-current protection ensure robust operation across −40°C to +125°C junction temperature.

Key Specifications

Pinout & Package

LP3879SD-1.2/NOPB is housed in an 8-pin WSON (NGT) package with exposed thermal pad, measuring 4.0 mm × 4.0 mm × 0.8 mm max height. The thermally enhanced layout requires soldering the exposed pad to a PCB copper pour for optimal θ_J−A ≈ 40°C/W and reliable 800 mA operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise, fixed-output LDO applications.

Compared with TPS7A2012PDBVR and TPL7407LPGEDR, LP3879SD-1.2/NOPB uniquely combines 800 mA output, remote SENSE, and ceramic-stable 1.2 V regulation-making it irreplaceable in high-performance digital power delivery where noise, accuracy, and load regulation are co-critical.

Availability

LP3879SD-1.2/NOPB is available at Aetrix Electronics and suitable for FPGA core supplies, medical diagnostic equipment, and notebook ASIC power applications requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant WSON packaging.

Supply support for LP3879SD-1.2/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 leader specializing in analog, embedded processing, and power management ICs, with decades of LDO design expertise and broad automotive, industrial, and personal electronics reach.

LP3879SD-1.2/NOPB belongs to TI's micropower, low-noise LDO family engineered specifically for noise-sensitive, low-voltage digital loads-including FPGA, ASIC, and DSP core supplies-where ceramic capacitor compatibility and precise 1.2 V regulation are essential.

FAQ

What is the maximum continuous output current of the LP3879SD-1.2/NOPB?

The LP3879SD-1.2/NOPB delivers up to 800 mA continuously under thermal limits defined by PCB layout. Its peak output current reaches 1200 mA for short durations, supporting transient-heavy digital loads. Actual sustained current depends on ambient temperature, copper area, and airflow-TI specifies θ_J−A ≈ 40°C/W for the WSON package on a 4-layer board with thermal vias.

Does the LP3879SD-1.2/NOPB require an external bypass capacitor, and why?

Yes-the LP3879SD-1.2/NOPB requires a 10 nF capacitor between the BYPASS pin and ground. This capacitor reduces broadband output noise to 18 µV_RMS and provides critical phase lead for loop stability. Leakage must stay below 100 nA to avoid output voltage error; NPO/COG ceramic or polypropylene film capacitors are recommended.

Can the LP3879SD-1.2/NOPB operate with a 2.2 V input supply?

No-the LP3879SD-1.2/NOPB has a minimum input voltage of 2.5 V to maintain regulation at 800 mA load. At 1.2 V output, the dropout voltage is ~1.3 V under full load, so 2.2 V input falls below specification and will cause output collapse. Input must be ≥2.5 V across all operating conditions including line and temperature variation.

How does the SENSE pin improve regulation in the LP3879SD-1.2/NOPB?

The SENSE pin enables remote sensing by connecting directly to the load's power input node-bypassing PCB trace resistance. This eliminates voltage drop errors caused by trace IR loss, improving load regulation accuracy from typical ±2% to ±0.5% over 0–800 mA. For best results, route SENSE separately from OUTPUT and avoid shared return paths.

Is the LP3879SD-1.2/NOPB pin-compatible with other LP3879 variants like LP3879MR-1.2/NOPB?

No-LP3879SD-1.2/NOPB uses the 8-pin WSON (NGT) package, while LP3879MR-1.2/NOPB uses the 8-pin SO PowerPad (DDA) package. Though both have identical pin functions and electrical specs, their footprints, thermal pads, and solder stencil requirements differ. PCB layout and assembly processes are not interchangeable between SD and MR variants.