Texas Instruments LP3893ES-1.2/NOPB

Overview

LP3893ES-1.2/NOPB from Texas Instruments is a 3A ultra-low-dropout linear regulator with 1.2V fixed output, fabricated in CMOS process using an N-MOS pass transistor; features 270 mV typical dropout at 3A, 1.5% output accuracy at 25°C, and −40°C to +125°C junction temperature range; used as post-regulator for DSP core supplies and server I/O rails where fast transient response and low quiescent current are critical.

For engineers reviewing the LP3893ES-1.2/NOPB datasheet, LP3893ES-1.2/NOPB pinout, LP3893ES-1.2/NOPB application, or LP3893ES-1.2/NOPB equivalent, key selection criteria include bias rail dependency (4.5–6V VBIAS), shutdown threshold (0.3V/1.3V), thermal derating for DDPAK/TO-263 package, and mandatory 10 µF minimum output capacitance with ESR constraints.

Technical Context

The LP3893ES-1.2/NOPB employs a dual-rail architecture: VIN supplies load power while VBIAS (4.5–6V) drives the N-MOS gate, enabling operation with input voltages as low as VOUT + VDO; its CMOS design delivers 60 nA shutdown current and maintains <0.04%/A load regulation across 10 mA–3A.

Stability requires external 10 µF input/output capacitors with specific ESR limits (0.001–1 Ω over load range); tantalum is recommended for output due to stable ESR vs. temperature, while ceramic is acceptable only up to 15% of total output capacitance; PSRR reaches 80 dB at 120 Hz on VIN and 70 dB on VBIAS.

Key Specifications

Pinout & Package

LP3893ES-1.2/NOPB uses the DDPAK/TO-263 (KTT) 5-pin thermally enhanced package with exposed thermal pad; pin 1 is GND, pin 2 is VIN, pin 3 is VBIAS, pin 4 is S/D, pin 5 is VOUT - verified per TI SNVS237B Figure 2 and Package Option Addendum.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPL7407LPGEDR and TPS7A8300RGRT, the LP3893ES-1.2/NOPB uniquely balances 3A output, ultra-low dropout, and dual-rail flexibility-enabling designs where VIN is constrained below 2V while maintaining full load capability and thermal robustness in TO-263 packaging.

Availability

LP3893ES-1.2/NOPB is available at Aetrix Electronics and suitable for DSP core power supplies, server I/O rail regulation, and microcontroller core voltage applications requiring stable component supply, long-term lifecycle support, and RoHS-exempt compliance for industrial deployment.

Supply support for LP3893ES-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 company headquartered in Dallas, Texas, specializing in analog, embedded processing, and power management ICs with broad industrial, automotive, and communications market reach.

The LP3893ES-1.2/NOPB belongs to TI's ultra-low-dropout linear regulator product line, engineered specifically for high-current, fast-transient applications demanding precision voltage regulation in space-constrained and thermally demanding environments.

FAQ

What is the minimum input voltage required for LP3893ES-1.2/NOPB to regulate 1.2V output at 3A load?

The LP3893ES-1.2/NOPB requires a minimum input voltage of VOUT + VDO = 1.2V + 0.27V = 1.47V at 3A (typical dropout). However, VIN must also satisfy the recommended operating condition: (VOUT + VDO) to 5.5V. The actual minimum depends on temperature and tolerance - worst-case dropout is 650 mV, so VIN ≥ 1.85V ensures regulation across full temperature and process variation. VBIAS must remain within 4.5–6V independently.

Does LP3893ES-1.2/NOPB require an external bias voltage, and what happens if VBIAS falls below specification?

Yes, LP3893ES-1.2/NOPB requires an external VBIAS rail between 4.5V and 6V to drive the N-MOS gate; if VBIAS drops below ~4V, an internal under-voltage lockout disables the output to prevent unstable regulation. This behavior is documented in the Application Hints section of the SNVS237B datasheet and protects against partial turn-on of the pass device.

What output capacitor types and values are mandatory for stable operation of LP3893ES-1.2/NOPB?

LP3893ES-1.2/NOPB requires ≥10 µF output capacitance with ESR between 0.001 Ω and 1 Ω over the full operating temperature range. Tantalum capacitors are recommended due to stable ESR vs. temperature; aluminum electrolytics are restricted to >10°C environments; ceramic capacitors alone are unsuitable but may supplement up to 15% of total capacitance.

How does the shutdown function operate on LP3893ES-1.2/NOPB, and what is the recommended interface?

The S/D pin on LP3893ES-1.2/NOPB is active-low: output turns off when S/D ≤ 0.3V (typ) and turns on when ≥ 1.3V (typ). A pull-up resistor (10–100 kΩ to VBIAS or VIN) is required unless driven by a rail-to-rail CMOS output. The shutdown current is 60 nA typical, and turn-off delay is 20 µs - critical for sequencing in multi-rail systems.

What thermal considerations apply to LP3893ES-1.2/NOPB in the DDPAK/TO-263 package?

In the DDPAK/TO-263 (KTT) package, LP3893ES-1.2/NOPB relies on PCB copper area for heatsinking: θJA ≈ 40°C/W with ≥1.5 in² copper. Maximum power dissipation is limited by junction temperature (125°C max); PD = (VIN−VOUT)×IOUT + VIN×IGND. For 3A at VIN = 2.5V, PD ≈ 3.9W - requiring ≥2.5 in² copper or forced air cooling to avoid thermal shutdown.