Texas Instruments LP2985AITP-1.8/NOPB

Overview

LP2985AITP-1.8/NOPB from Texas Instruments is a micropower, low-noise, ultra-low-dropout linear regulator delivering 150 mA at fixed 1.8 V output with ±1% accuracy (A-grade), 280 mV typical dropout at full load, and 30 µV_RMS output noise when using a 10-nF bypass capacitor - designed for power-sensitive portable electronics requiring stable low-voltage rail generation.

For engineers reviewing the LP2985AITP-1.8/NOPB datasheet, LP2985AITP-1.8/NOPB pinout, LP2985AITP-1.8/NOPB application, or LP2985AITP-1.8/NOPB equivalent, key selection considerations include its SOT-23-5 package compatibility, shutdown quiescent current < 1 µA, ceramic-capacitor stability down to 5 mΩ ESR, and guaranteed operation across −40°C to +125°C junction temperature.

Technical Context

The LP2985AITP-1.8/NOPB employs a vertically integrated PNP (VIP) process enabling ultra-low ground current (825 µA at 150 mA load) and sub-300 mV dropout while maintaining high PSRR (45 dB at 1 kHz) and low output impedance (0.3 Ω typical, 10 Hz–1 MHz). Its internal bandgap reference feeds a precision error amplifier controlling the pass transistor, with dedicated BYPASS pin enabling external noise filtering via a 10-nF capacitor.

Functional modes are managed through the ON/OFF pin: logic-high (>1.6 V) enables regulation with fast start-up; logic-low (<0.15 V) forces shutdown with <2 µA total current draw. Protection includes foldback current limiting (400 mA short-circuit peak) and thermal shutdown, with stability ensured across 1–150 mA load range using ≥2.2 µF ceramic output capacitance.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm body, 0.95 mm height, gull-wing leads; thermally enhanced for PCB heat dissipation in high-density layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPL720F18, LP2985AITP-1.8/NOPB offers proven SOT-23-5 manufacturability and integrated ON/OFF control; versus MCP1700T-1802E/MB, it delivers 43% lower dropout and 25% lower noise while supporting active power management - making it superior for battery longevity and signal integrity in portable medical and industrial edge devices.

Availability

LP2985AITP-1.8/NOPB is available at Aetrix Electronics and suitable for wearable health monitors, industrial sensor nodes, smartphone baseband subsystems, and portable medical diagnostics requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for LP2985AITP-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 leader specializing in analog, embedded processing, and connectivity technologies, with decades of LDO design heritage focused on power efficiency and signal integrity.

The LP2985LV-N product line was engineered specifically for ultra-low-noise, micropower regulation in battery-powered portable electronics - emphasizing minimal dropout, ceramic-capacitor compatibility, and sub-µA shutdown for extended runtime.

FAQ

What is the minimum input voltage required for LP2985AITP-1.8/NOPB to maintain regulation at 150 mA load?

The LP2985AITP-1.8/NOPB requires a minimum input voltage of 2.08 V at 25°C (2.2 V over full temperature range) to sustain 1.8 V output regulation at 150 mA, based on its 280 mV typical dropout voltage. This allows reliable operation from partially discharged single-cell Li-ion batteries down to ~2.1 V, maximizing usable energy per charge cycle.

Can LP2985AITP-1.8/NOPB operate without the BYPASS capacitor?

Yes, LP2985AITP-1.8/NOPB functions without the BYPASS capacitor, delivering standard 1.8 V output with ±1% accuracy and full 150 mA capability. However, omitting the 10-nF ceramic capacitor on the BYPASS pin increases output noise from 30 µV_RMS to approximately 100 µV_RMS, which may degrade performance in noise-sensitive applications like precision ADCs or RF synthesizers.

Is LP2985AITP-1.8/NOPB pin-compatible with other LP2985 variants such as LP2985-1.8/NOPB?

No, LP2985AITP-1.8/NOPB is not pin-compatible with LP2985-1.8/NOPB. The "A" suffix denotes A-grade (±1% output tolerance), while "TP" indicates tape-and-reel packaging - both share identical SOT-23-5 pinout and electrical behavior. However, non-A-grade versions (e.g., LP2985-1.8/NOPB) have ±1.5% tolerance and differ only in test screening, not pin assignment or function.

What output capacitor value and type does TI recommend for stable operation of LP2985AITP-1.8/NOPB?

Texas Instruments specifies a minimum 2.2 µF ceramic output capacitor with ESR ≤5 mΩ for stable operation of LP2985AITP-1.8/NOPB across 1–150 mA load and −40°C to +125°C. X5R or X7R dielectrics are acceptable if capacitance remains ≥2.2 µF over temperature; placement must be ≤1 cm from OUT and GND pins with low-inductance routing to ensure phase margin.

Does LP2985AITP-1.8/NOPB require an input capacitor, and what are the requirements?

Yes, LP2985AITP-1.8/NOPB requires a minimum 1 µF ceramic input capacitor between IN and GND, placed ≤1 cm from the IN pin and connected to a clean analog ground. No ESR requirement exists, but capacitor tolerance and temperature coefficient must guarantee ≥1 µF across the full operating range; X5R/X7R ceramics are preferred for stability and size efficiency.