Texas Instruments LP2985AIM5X-5.0

Overview

LP2985AIM5X-5.0 from Texas Instruments is a micropower, ultra-low-dropout linear regulator in SOT-23-5 package delivering 150 mA output current with 5.0 V fixed output, ±1% accuracy (A-grade), 300 mV typical dropout at full load, and 30 µV_RMS output noise (300 Hz–50 kHz) when using a 10 nF bypass capacitor. It serves as a precision, low-noise power supply for battery-powered portable electronics requiring stable voltage under light-to-moderate loads.

For engineers reviewing the LP2985AIM5X-5.0 datasheet, LP2985AIM5X-5.0 pinout, LP2985AIM5X-5.0 application, or LP2985AIM5X-5.0 equivalent, key selection considerations include its 5.0 V fixed output, shutdown-enabled ON/OFF control (≤2 µA quiescent in sleep mode), compatibility with low-ESR ceramic capacitors (≥2.2 µF C_OUT, ≥1 µF C_IN), and thermal/overcurrent protection - all critical for space-constrained, energy-sensitive designs.

Technical Context

The LP2985AIM5X-5.0 employs a vertically integrated PNP (VIP) pass transistor architecture enabling ultra-low dropout (as low as 7 mV at 1 mA) and exceptionally low ground current (75 µA at 1 mA, 850 µA at 150 mA). Its internal reference and feedback loop are optimized for stability with ceramic output capacitors down to 5 mΩ ESR, eliminating need for tantalum or electrolytic types.

It integrates active ON/OFF control logic: pulling the ON/OFF pin below 0.15 V disables regulation and reduces quiescent current to ≤2 µA; raising it above 1.6 V initiates startup. The BYPASS pin provides direct access to the internal reference node, allowing external 10 nF capacitor placement to suppress reference noise and achieve 30 µV_RMS total output noise.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm footprint, surface-mount, thermally enhanced plastic case with exposed pad (not electrically connected in standard DBV variant).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise, 5 V fixed-output LDO applications.

Compared with MCP1700T-5002E/TT, LP2985AIM5X-5.0 offers superior noise performance and active shutdown, but trades off slightly higher quiescent current; versus TLS850B2TE/V33, it provides exact 5.0 V output and industrial temperature range at lower cost and complexity, though without automotive qualification.

Availability

LP2985AIM5X-5.0 is available at Aetrix Electronics and suitable for cellular handsets, wearable health monitors, industrial data loggers, and point-of-sale terminals requiring stable component supply, long-term manufacturability, and consistent parametric performance across production lots.

Supply support for LP2985AIM5X-5.0 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, designing and manufacturing analog ICs, embedded processors, and system-on-chip solutions for industrial, automotive, and personal electronics markets.

The LP2985-N series was developed specifically for micropower, ultra-low-noise, ultra-low-dropout regulation in battery-powered portable devices - emphasizing precision output, minimal quiescent consumption, and robust ceramic-capacitor compatibility.

FAQ

What is the maximum input voltage rating for LP2985AIM5X-5.0?

The LP2985AIM5X-5.0 has an absolute maximum input voltage rating of 16 V and a recommended operating input range of 2.5 V to 16 V. Exceeding 16 V may cause permanent damage. For reliable operation, VIN should remain ≥5.6 V (5.0 V + 600 mV headroom) to maintain regulation under worst-case dropout conditions across temperature and load.

Does LP2985AIM5X-5.0 require an external bypass capacitor to achieve its specified 30 µV_RMS noise performance?

Yes, LP2985AIM5X-5.0 achieves its 30 µV_RMS output noise specification (300 Hz–50 kHz) only when a 10 nF ceramic capacitor is placed between the BYPASS pin and GND. Without this capacitor, output noise increases significantly - typically exceeding 100 µV_RMS. The BYPASS capacitor must be low-leakage (e.g., X7R or C0G dielectric) and placed close to the device.

Can LP2985AIM5X-5.0 operate with a 2.2 µF ceramic output capacitor as stated in the datasheet?

Yes, LP2985AIM5X-5.0 is explicitly designed and characterized for stability with a minimum 2.2 µF ceramic output capacitor having ESR as low as 5 mΩ. This eliminates the need for larger, higher-ESR tantalum or aluminum electrolytic capacitors. Increasing C_OUT beyond 2.2 µF improves transient response and further reduces output impedance without compromising stability.

What is the shutdown current of LP2985AIM5X-5.0 when the ON/OFF pin is pulled low?

When the ON/OFF pin voltage is held below 0.15 V, LP2985AIM5X-5.0 enters shutdown mode and draws ≤2 µA total supply current over the full −40°C to +125°C junction temperature range. This ultra-low shutdown current makes it ideal for battery-powered systems requiring extended storage or deep-sleep states without significant self-discharge.

Is LP2985AIM5X-5.0 compatible with ceramic input capacitors?

Yes, LP2985AIM5X-5.0 requires a minimum 1 µF ceramic input capacitor (X5R or X7R) placed within 1 cm of the IN and GND pins. Ceramic capacitors are preferred due to their low ESR and stable capacitance over temperature and voltage. Tantalum or film capacitors may also be used, but ceramics offer superior size, reliability, and cost efficiency for this application.