Texas Instruments LP3963ES-3.3/NOPB

Overview

LP3963ES-3.3/NOPB from Texas Instruments is a 3A ultra-low-dropout linear regulator with fixed 3.3V output, designed for high-current microprocessor and DSP power supplies. It delivers ±1.5% output voltage accuracy at room temperature, 800mV dropout at 3A load, and features an error flag for output monitoring. Its CMOS architecture enables 15µA shutdown current and low ground pin current (6mA at 3A), making it suitable for battery-powered and thermally constrained applications.

For engineers reviewing the LP3963ES-3.3/NOPB datasheet, LP3963ES-3.3/NOPB pinout, LP3963ES-3.3/NOPB application, or LP3963ES-3.3/NOPB equivalent, key selection criteria include dropout performance under full 3A load, error flag response to 10% output deviation, thermal shutdown threshold at 165°C, and compatibility with 33µF/3Ω-output-capacitor stability requirements.

Technical Context

The LP3963ES-3.3/NOPB uses a PMOS pass transistor with 240mΩ typical R_DS(on), enabling ultra-low dropout operation down to 80mV at 300mA and 800mV at 3A. Its error flag circuitry monitors regulated output voltage with ±5% hysteresis and asserts low when V_OUT drops >10% below nominal - a dedicated fault indicator not present in the LP3966 variant.

Operating from 2.5V–7.0V input, it maintains 0.06% load regulation and 0.02% line regulation across its full 3A DC output range. The device integrates overtemperature (165°C shutdown) and overcurrent protection, with peak current limiting at 4.5A and short-circuit current of 5.5A - all implemented without external components.

Key Specifications

Pinout & Package

LP3963ES-3.3/NOPB is packaged in the DDPAK/TO-263-5 surface-mount package, featuring exposed thermal pad for enhanced heat dissipation in high-power applications. The 5-pin layout supports compact PCB integration while maintaining robust thermal performance up to 125°C junction temperature.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 3A fixed-output LDO applications.

Compared with TPS75733KTTT and LT1963AES-3.3, the LP3963ES-3.3/NOPB uniquely combines 3A capability, integrated error flag, and ultra-low dropout in a single DDPAK package - enabling simpler, more reliable power architectures for high-density digital systems.

Availability

LP3963ES-3.3/NOPB is available at Aetrix Electronics and suitable for microprocessor core supplies, GTL bus terminators, DSP power management, SCSI interface supplies, and high-efficiency linear regulators requiring stable component supply across industrial, computing, and communications applications.

Supply support for LP3963ES-3.3/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 technologies, with decades of expertise in high-reliability linear regulators and power solutions.

The LP3963 series belongs to TI's ultra-low-dropout LDO portfolio, engineered specifically for high-current, low-voltage digital systems where transient response, thermal robustness, and fault visibility are critical - including FPGA, DSP, and memory interface power rails.

FAQ

What is the minimum input voltage required for LP3963ES-3.3/NOPB to regulate 3.3V at 3A?

The LP3963ES-3.3/NOPB requires a minimum input voltage of 4.1V to maintain regulation at 3A, based on its 800mV typical dropout voltage (3.3V + 0.8V). Below this, output voltage collapses proportionally. The absolute minimum operating VIN is defined as V_OUT(NOM) + V_DROPOUT, not the 2.5V absolute rating - which only applies at lighter loads.

Does LP3963ES-3.3/NOPB require an external resistor network to set output voltage?

No. LP3963ES-3.3/NOPB is a fixed-output device with internally trimmed 3.3V regulation - no external resistors are needed. This contrasts with the adjustable LP3966 variant, which uses an SENSE/ADJ pin and external divider. The LP3963ES-3.3/NOPB simplifies design by eliminating tuning components and associated layout sensitivity.

Can the ERROR pin of LP3963ES-3.3/NOPB be left floating?

No. The ERROR pin is an open-drain output and must be pulled high with a 10kΩ–1MΩ resistor to VIN. Leaving it floating results in undefined logic state and potential system misdiagnosis. If unused, TI documentation explicitly requires connecting ERROR directly to GND to disable the function safely and reduce leakage.

What output capacitor ESR range ensures stability for LP3963ES-3.3/NOPB?

LP3963ES-3.3/NOPB requires an output capacitor with ESR between 0.2Ω and 5Ω for guaranteed stability across temperature and load. Ceramic capacitors alone are unsuitable due to sub-10mΩ ESR; recommended solutions include 33µF solid tantalum or hybrid networks (e.g., 100µF tantalum + 3µF ceramic) meeting the ESR window.

How does thermal shutdown behave in LP3963ES-3.3/NOPB during sustained overload?

When junction temperature reaches 165°C, LP3963ES-3.3/NOPB initiates thermal shutdown with 10°C hysteresis. It cycles the PMOS pass element on/off to limit average power dissipation until temperature falls to 155°C, then resumes normal regulation. This protects against permanent damage while allowing automatic recovery once cooling occurs - no manual reset required.