Texas Instruments LP5951MF-2.8

Overview

LP5951MF-2.8 from Texas Instruments is a micropower, 150-mA low-dropout CMOS voltage regulator in SC70-5 package, delivering a fixed 2.8 V output with 29 µA typical quiescent current, 250 mV dropout at 150 mA, and ±2 mV line transient response - deployed in battery-powered portable electronics requiring stable low-noise supply under light-load conditions.

For engineers reviewing the LP5951MF-2.8 datasheet, LP5951MF-2.8 pinout, LP5951MF-2.8 application, or LP5951MF-2.8 equivalent, key selection considerations include its active-high enable control, 1.8–5.5 V input range, SC70-5 thermal performance (RθJA = 276.7°C/W), shutdown current <1 nA, and compatibility with 1-µF ceramic output capacitors.

Technical Context

The LP5951MF-2.8 integrates a PMOS pass device with internal bias generator, over-current and thermal protection circuitry, and logic-controlled enable functionality. Its architecture ensures no-load stability and fast 30 µs turn-on time via optimized ramp control.

It operates across –40°C to 125°C junction temperature, supports 1.3–3.7 V fixed-output variants, and maintains regulation down to 1.8 V input - with dropout defined as VIN–VOUT differential causing 100 mV drop below nominal output (not applicable below 1.8 V).

Key Specifications

Pinout & Package

LP5951MF-2.8 is housed in a 2.00 mm × 1.25 mm SC70-5 package with 0.65 mm pitch, optimized for space-constrained portable PCBs and supporting reflow soldering per JEDEC J-STD-020 (260°C peak Pb-free).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TSS721AIDBVR and MCP1700T-2802E/TT, the LP5951MF-2.8 uniquely balances ultra-low IQ (29 µA), fast enable response (30 µs), SC70-5 miniaturization, and robust 150 mA capability - making it optimal for battery-constrained, dynamically powered systems where size, efficiency, and control granularity are co-prioritized.

Availability

LP5951MF-2.8 is available at Aetrix Electronics and suitable for wireless sensor nodes, wearable health monitors, industrial handheld scanners, and smart meter RTC backup circuits requiring stable component supply with guaranteed long-term manufacturability.

Supply support for LP5951MF-2.8 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 connectivity solutions for industrial, automotive, and consumer markets.

The LP5951MF-2.8 belongs to TI's micropower LDO family engineered specifically for portable battery-powered systems - emphasizing ultra-low quiescent current, small-footprint packaging, and stability with minimal external components.

FAQ

What is the minimum input voltage required for LP5951MF-2.8 to regulate at 2.8 V?

The LP5951MF-2.8 requires VIN ≥ VOUT + VDO, where VDO is 250 mV at 150 mA. Thus, minimum functional input is 3.05 V under full load. However, the device's internal circuitry activates at 1.8 V, and regulation begins once VIN reaches 3.05 V - not 1.8 V alone. Below that threshold, output follows input without regulation.

Can LP5951MF-2.8 operate without an output capacitor?

No - the LP5951MF-2.8 requires a minimum 0.7 µF ceramic output capacitor (1 µF recommended) for stability. While it remains in regulation with no load, removing COUT causes oscillation and loss of regulation. The device is explicitly designed for 1 µF X7R/X5R ceramics, not for capacitor-less operation.

Is the NC pin on LP5951MF-2.8 safe to connect to ground?

The NC pin (Pin 4) has no internal connection and must remain unconnected. TI documentation explicitly states it is not bonded; grounding or routing it may introduce parasitic coupling or violate package design rules. Best practice is to leave it floating and exclude from copper pours or vias.

Does LP5951MF-2.8 support reverse current protection?

The LP5951MF-2.8 does not include active reverse current blocking. Its PMOS pass device contains a parasitic body diode that conducts if VOUT exceeds VIN. Current is limited to 50 mA in this condition; beyond that, an external Schottky diode (cathode to VIN, anode to VOUT) is required to prevent backfeed.

What is the thermal shutdown behavior of LP5951MF-2.8 during sustained overload?

When junction temperature reaches 160°C (typ.), LP5951MF-2.8 enters thermal shutdown, turning off the PMOS pass device. It remains off until temperature drops by ~20°C (hysteresis), then resumes regulation. This results in pulsed output during continuous overload - protecting the device but requiring derating or heatsinking for steady-state 150 mA operation in warm environments.