Texas Instruments LP2985IM5X-2.7/NOPB

Overview

LP2985IM5X-2.7/NOPB from Texas Instruments is a micropower, ultra-low-dropout linear regulator delivering 150 mA output current with 2.7 V fixed output, 300 mV typical dropout at full load, <75 µA quiescent current at 1 mA, 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 LP2985IM5X-2.7/NOPB datasheet, LP2985IM5X-2.7/NOPB pinout, LP2985IM5X-2.7/NOPB application, or LP2985IM5X-2.7/NOPB equivalent, key selection criteria include guaranteed 150 mA output with ≤575 mV max dropout over temperature, 1% output voltage accuracy (A-grade), shutdown current <2 µA, stability with 2.2 µF ceramic output capacitors (ESR ≥5 mΩ), and integrated thermal/overcurrent protection.

Technical Context

The LP2985IM5X-2.7/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% initial accuracy and maintain regulation with line changes up to 0.032%/V and load changes up to ±3.5% over –40°C to 125°C.

It integrates an ON/OFF control input with defined logic thresholds (enable >1.6 V, disable <0.15 V), foldback current limiting (400 mA short-circuit, 350 mA peak), and thermal shutdown. The BYPASS pin enables external noise filtering via a 10 nF capacitor, reducing broadband RMS noise to 30 µV while preserving PSRR >45 dB at 1 kHz.

Key Specifications

Pinout & Package

SOT-23 (DBV) 5-pin package: 2.90 mm × 1.60 mm footprint, surface-mount, thermally enhanced for PCB heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-2702E/MB and TLC7701QDCKR, the LP2985IM5X-2.7/NOPB uniquely combines 150 mA delivery, <2 µA shutdown, and 30 µV_RMS noise via BYPASS - making it the only option among the three qualified for high-fidelity analog and battery-constrained RF subsystems.

Availability

LP2985IM5X-2.7/NOPB is available at Aetrix Electronics and suitable for cellular phones, portable medical sensors, Bluetooth audio modules, and industrial handheld scanners requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for LP2985IM5X-2.7/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 specializing in analog, embedded processing, and power management technologies, with decades of leadership in precision linear regulators and low-power system solutions.

The LP2985-N product line was designed specifically for battery-powered portable electronics demanding ultra-low dropout, micropower operation, and low-noise regulation - targeting applications where efficiency, size, and signal integrity are critical constraints.

FAQ

What is the maximum input voltage rating for the LP2985IM5X-2.7/NOPB?

The LP2985IM5X-2.7/NOPB has an absolute maximum input voltage rating of 16 V and a recommended operating input range of 3.1 V to 16 V. This allows safe operation from multi-cell battery stacks or industrial 12 V rails while maintaining regulation down to 2.7 V output. Exceeding 16 V risks permanent damage per the Absolute Maximum Ratings table in the TI datasheet SNVS018Y.

Does the LP2985IM5X-2.7/NOPB require an external bypass capacitor to achieve its specified 30 µV_RMS noise performance?

Yes, the LP2985IM5X-2.7/NOPB achieves its 30 µV_RMS output noise (300 Hz–50 kHz) only when a 10 nF ceramic capacitor is connected between the BYPASS pin and GND. Without this capacitor, noise rises significantly - typically exceeding 100 µV_RMS. The BYPASS pin directly accesses the internal reference node, so the capacitor shunts high-frequency reference noise before it modulates the output.

Can the LP2985IM5X-2.7/NOPB operate stably with a 1 µF ceramic output capacitor?

No - the LP2985IM5X-2.7/NOPB requires a minimum 2.2 µF ceramic output capacitor for guaranteed stability across all load and temperature conditions. Using only 1 µF violates the design requirement stated in Section 8.2.2.1.2 of the datasheet and risks oscillation or poor transient response, especially at higher loads. The 2.2 µF value ensures phase margin remains adequate with ESR as low as 5 mΩ.

What is the guaranteed minimum output current capability of the LP2985IM5X-2.7/NOPB over temperature?

The LP2985IM5X-2.7/NOPB is specified to deliver 150 mA continuously across the full operating junction temperature range of –40°C to 125°C. This is confirmed in Section 6.3 (Recommended Operating Conditions) and Section 6.5 (Electrical Characteristics), where output current is listed as 150 mA with no derating applied. Thermal shutdown protects the device if power dissipation exceeds safe limits.

How does the ON/OFF pin logic threshold behave across temperature for the LP2985IM5X-2.7/NOPB?

The ON/OFF pin of the LP2985IM5X-2.7/NOPB has a guaranteed high-enable threshold of ≥1.6 V and a low-disable threshold of ≤0.15 V across –40°C to 125°C. These values are specified in Section 6.5 (Electrical Characteristics) under "V_ON/OFF" test conditions. At room temperature, typical enable occurs at ~1.4 V and disable at ~0.55 V, but designs must use the worst-case limits for robustness.