Texas Instruments LP5951MG-2.5

Overview

LP5951MG-2.5 from Texas Instruments is a micropower, 150-mA low-dropout CMOS voltage regulator in SC70-5 package, delivering a fixed 2.5 V output with 250 mV dropout at 150 mA, 29 µA quiescent current, and ±2 mV line transient response. It serves as a precision power rail for battery-powered microcontrollers, sensors, and RF front-ends requiring stable low-noise supply under dynamic load.

For engineers reviewing the LP5951MG-2.5 datasheet, LP5951MG-2.5 pinout, LP5951MG-2.5 application, or LP5951MG-2.5 equivalent, key selection considerations include its 1.8–5.5 V input range, logic-controlled enable (0.4 V/0.9 V thresholds), thermal shutdown at 160°C, stability with 1-µF ceramic capacitors, and guaranteed 150-mA output current across –40°C to 125°C.

Technical Context

The LP5951MG-2.5 employs a PMOS pass device architecture enabling ultra-low quiescent current and reverse-current protection via inherent body diode control. Its internal bias generator and LDO core deliver fast 30 µs turn-on time and maintain regulation down to zero load-critical for CMOS RAM keep-alive circuits.

Enable functionality operates with active-high logic: EN ≥0.9 V enables regulation; EN ≤0.4 V forces shutdown with <1 nA quiescent current. The NC pin has no internal connection, and thermal overload protection engages at 160°C with 20°C hysteresis, cycling output during sustained fault conditions.

Key Specifications

Pinout & Package

LP5951MG-2.5 is housed in a 2.00 mm × 1.25 mm SC70-5 surface-mount package optimized for space-constrained portable designs. Thermal resistance R_θJA is 276.7°C/W, requiring minimal copper area for thermal management in low-power applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LP5951MG-2.5, TPL720F12-DBVR offers higher output current but cannot replace it in 2.5 V–dependent circuits, while MCP1700T-2502E/TT eliminates enable control and trades off programmable shutdown for ultra-low 1.8 µA IQ-making LP5951MG-2.5 optimal for applications needing both precision 2.5 V and active power sequencing.

Availability

LP5951MG-2.5 is available at Aetrix Electronics and suitable for wearable electronics, industrial sensor networks, portable medical devices, and battery-powered instrumentation requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for LP5951MG-2.5 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 and embedded processing technologies, with leadership in power management ICs for portable and industrial applications.

The LP5951 product line delivers micropower LDO regulators optimized for space- and energy-constrained battery-operated systems, emphasizing ultra-low IQ, fast transient response, and robust protection features across extended temperature ranges.

FAQ

What is the maximum input voltage for LP5951MG-2.5?

The LP5951MG-2.5 supports an absolute maximum input voltage of 6.5 V on the IN pin relative to GND. However, its recommended operating range is 1.8 V to 5.5 V. Exceeding 5.5 V may trigger internal protection or degrade reliability. For continuous operation, VIN must remain ≥(VOUT + VDO) = 2.75 V to maintain regulation.

Does LP5951MG-2.5 require external capacitors, and what values are recommended?

Yes, LP5951MG-2.5 requires both input and output capacitors for stability. A minimum 1-µF ceramic capacitor (X7R or X5R dielectric) is recommended on IN, placed within 1 cm of the pin. For OUT, a 1-µF ceramic capacitor with ESR between 3 mΩ and 300 mΩ is specified; values up to 47 µF are acceptable. Tantalum capacitors are discouraged due to surge current risks and higher ESR.

Can LP5951MG-2.5 be used without connecting the EN pin?

No-LP5951MG-2.5's EN pin must not be left floating. To operate continuously, tie EN directly to VIN. Leaving it unconnected risks unpredictable behavior due to noise coupling or partial enable states. If shutdown control is unused, this direct connection ensures reliable full-enable operation across temperature and supply variations.

What is the thermal shutdown behavior of LP5951MG-2.5?

LP5951MG-2.5 activates thermal shutdown at approximately 160°C junction temperature and re-enables at ~140°C (20°C hysteresis). During sustained overload, this causes pulsed output operation-repeated on/off cycling-to prevent permanent damage. The device does not latch off; normal regulation resumes once junction temperature falls below the hysteresis threshold.

Is LP5951MG-2.5 compatible with ceramic capacitors smaller than 1 µF?

No-LP5951MG-2.5 is characterized and guaranteed stable only with output capacitance ≥1 µF. Using smaller values (e.g., 0.47 µF) risks oscillation, degraded PSRR, and poor load transient response. The datasheet specifies 0.7 µF as the absolute minimum including tolerance and bias derating, but 1 µF is the validated design point for all performance metrics including ±2 mV line transients and –60 dB PSRR.