Texas Instruments LP2985AIM5X-3.6/NOPB

Overview

LP2985AIM5X-3.6/NOPB from Texas Instruments is a micropower, ultra-low-dropout linear regulator delivering 150 mA output current with 3.6 V fixed output voltage, 1% accuracy (A-grade), 350 mV max dropout at 150 mA, and 75 µA quiescent current at 1 mA load - designed for battery-powered portable electronics requiring low noise and high efficiency.

For engineers reviewing the LP2985AIM5X-3.6/NOPB datasheet, LP2985AIM5X-3.6/NOPB pinout, LP2985AIM5X-3.6/NOPB application, or LP2985AIM5X-3.6/NOPB equivalent, key selection considerations include guaranteed 150 mA output under 300 mV dropout, < 30 µV_RMS output noise with 10 nF bypass capacitor, shutdown current < 0.01 µA, stability with 5 mΩ ESR ceramic capacitors, and SOT-23-5 package compatibility in space-constrained designs.

Technical Context

The LP2985AIM5X-3.6/NOPB employs a vertically integrated PNP (VIP) pass transistor architecture enabling ultra-low dropout and minimal ground current across load range. Its internal reference and error amplifier deliver 1% output voltage tolerance over –40°C to 125°C junction temperature, with line regulation of 0.014%/V and load regulation maintained within ±2.5% up to 150 mA.

It integrates active ON/OFF control logic with 1.6 V enable threshold and 0.15 V disable threshold, foldback current limiting (400 mA short-circuit, 350 mA peak), thermal shutdown, and enhanced phase margin compensation for stability with ultra-low-ESR ceramic output capacitors down to 5 mΩ - eliminating need for tantalum or electrolytic alternatives.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm body, 0.95 mm height, gull-wing leads, RoHS-compliant, tape-and-reel packaging.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LP2985AIM5X-3.6/NOPB, TLS850B0ELVSE offers higher current and automotive compliance but sacrifices 3.6 V output and bypass-enabled noise reduction; MCP1702T-3602E/MB provides lower quiescent current and same output voltage but omits ON/OFF control and noise optimization features - making LP2985AIM5X-3.6/NOPB uniquely balanced for portable, battery-sensitive, low-noise applications requiring all three capabilities.

Availability

LP2985AIM5X-3.6/NOPB is available at Aetrix Electronics and suitable for cellular handsets, wearable health monitors, industrial data loggers, and portable medical devices requiring stable component supply, long-term manufacturability, and RoHS-compliant packaging.

Supply support for LP2985AIM5X-3.6/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 designing analog ICs, embedded processors, and digital signal solutions for industrial, automotive, and consumer markets.

The LP2985-N product line delivers micropower, ultra-low-dropout, low-noise LDO regulators optimized for battery-powered portable electronics - emphasizing minimal dropout, precision output, and ceramic-capacitor compatibility in ultra-small SOT-23 packages.

FAQ

What is the maximum input voltage rating for LP2985AIM5X-3.6/NOPB?

The LP2985AIM5X-3.6/NOPB has an absolute maximum input voltage rating of 16 V and a recommended operating input voltage range of 3.1 V to 16 V. This upper limit ensures safe operation when used with higher-voltage battery stacks or unregulated supplies, while the 3.1 V minimum accounts for worst-case dropout and tolerance margins at full load. Exceeding 16 V risks permanent device damage per TI's Absolute Maximum Ratings table.

Does LP2985AIM5X-3.6/NOPB require an external bypass capacitor to achieve its specified 30 µV_RMS noise performance?

Yes, LP2985AIM5X-3.6/NOPB achieves its 30 µV_RMS output noise specification only when a 10 nF ceramic capacitor is connected between the BYPASS pin (Pin 4) and GND. Without this capacitor, output noise rises significantly - typically to ~120 µV_RMS. The BYPASS pin directly shunts internal reference noise, and omitting the capacitor forfeits the low-noise advantage that defines this regulator's value in precision analog and RF applications.

Can LP2985AIM5X-3.6/NOPB operate stably with a 1 µF ceramic output capacitor?

No, LP2985AIM5X-3.6/NOPB requires a minimum 2.2 µF ceramic output capacitor for guaranteed stability across all load and temperature conditions. While the device remains stable with ESR as low as 5 mΩ, TI's datasheet explicitly specifies 2.2 µF as the minimum capacitance value - verified through phase margin testing. Using only 1 µF may cause oscillation or poor transient response, especially near 150 mA load or at temperature extremes.

What is the ON/OFF pin logic threshold for enabling LP2985AIM5X-3.6/NOPB?

The ON/OFF pin of LP2985AIM5X-3.6/NOPB asserts logic-high enable when voltage exceeds 1.6 V (minimum) and asserts logic-low disable when voltage falls below 0.15 V (maximum), both specified over the full –40°C to 125°C junction temperature range. This hysteresis prevents chatter near the transition point. Pulling the pin to VIN (≥2.5 V) enables the device; connecting it to GND or a GPIO output <0.15 V disables it, reducing quiescent current to 0.01 µA.

Is LP2985AIM5X-3.6/NOPB compatible with ceramic capacitors having 2 mΩ ESR?

No, LP2985AIM5X-3.6/NOPB is specified for stable operation only with output capacitors exhibiting ESR ≥5 mΩ. While lower ESR improves transient response, TI's stability analysis confirms potential phase-margin degradation below 5 mΩ - risking oscillation. The device's internal compensation is optimized for ≥5 mΩ, and using 2 mΩ ceramics (e.g., high-end X7R or NP0 types) violates the validated design window and is not supported by TI's characterization data.