Microchip Technology LP2950-03BZ TR

Overview

LP2950-03BZ TR from Micrel is a 5.0V, ±1.0% initial accuracy, 100mA low-dropout linear voltage regulator in TO-92 package, featuring 380mV dropout at full load, 75µA typical quiescent current, and operation from –40°C to +125°C - designed for battery-powered instrumentation, automotive sensors, and low-power embedded systems requiring stable 5V supply with minimal standby drain.

For engineers reviewing the LP2950-03BZ TR datasheet, LP2950-03BZ TR pinout, LP2950-03BZ TR application, or LP2950-03BZ TR equivalent, key selection considerations include guaranteed 100mA output under dropout conditions, tight line/load regulation (≤0.40%), low temperature coefficient (50 ppm/°C), and compatibility with 1µF ceramic/tantalum output capacitance for stability.

Technical Context

The LP2950-03BZ TR uses a PNP pass transistor architecture enabling ultra-low dropout voltage and near-constant quiescent current across operating range - critical for extending battery runtime in portable devices. Its internal 1.235V bandgap reference provides stable regulation without external components.

Unlike switching regulators, it delivers inherently low-noise 5V output (430 µVRMS, 10Hz–100kHz) and supports zero-load operation - essential for CMOS RAM keep-alive and microcontroller sleep-mode applications where leakage must be minimized.

Key Specifications

Pinout & Package

LP2950-03BZ TR is housed in a 3-pin TO-92 plastic package (Z suffix), with leads spaced 0.100" (2.54 mm) and standard through-hole mounting. Pin 1 = Input, Pin 2 = Ground, Pin 3 = Output (bottom view).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LP2950-03BZ TR, TLV70033DCKR offers higher current and lower dropout but targets 3.3V systems and requires layout change, while MCP1700-5002E/TO matches the TO-92 form factor and 5V output but trades off proven automotive-grade temperature range (–40°C to +125°C) for ultra-low 1.6µA quiescent current.

Availability

LP2950-03BZ TR is available at Aetrix Electronics and suitable for automotive electronics, industrial RTUs, portable medical monitors, and avionics subsystems requiring stable component supply with long-term lifecycle visibility.

Supply support for LP2950-03BZ TR 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

Micrel Inc. was a U.S.-based semiconductor company specializing in analog, power management, and timing solutions before its acquisition by Microchip Technology in 2015. Known for robust industrial-grade LDOs and Ethernet PHYs.

The LP2950 series was developed as a micropower, high-accuracy LDO family targeting battery-critical applications including automotive, avionics, and portable instrumentation - emphasizing low dropout, zero-load stability, and wide-temperature reliability.

FAQ

What is the maximum input voltage rating for LP2950-03BZ TR?

The LP2950-03BZ TR has an absolute maximum input supply voltage of +30V. Operation above this level risks permanent damage. For continuous reliable operation, the recommended maximum input is 28V DC with adequate thermal management on the PCB, especially at high ambient temperatures or full 100mA load. The device maintains regulation down to VIN = VOUT + dropout voltage (e.g., 5.38V at 100mA), making it suitable for 6V–24V input systems.

Does LP2950-03BZ TR require an output capacitor, and what type is recommended?

Yes, LP2950-03BZ TR requires a minimum 1.0µF capacitor between output and ground for unconditional stability. Solid tantalum or aluminum electrolytic capacitors with ESR ≤5Ω are recommended; ceramic capacitors may be used if their effective series resistance is ≥0.5Ω or if a small series resistor (1–2Ω) is added. For operation below –25°C, solid tantalum is preferred due to better low-temperature performance than standard aluminum electrolytics.

Can LP2950-03BZ TR be used as a precision voltage reference?

Yes, LP2950-03BZ TR can serve as a low-power voltage reference due to its 1.235V internal bandgap reference, 50 ppm/°C temperature coefficient, and tight initial tolerance (±1.0% over temperature). When configured with no load and proper decoupling, its 5.0V output exhibits <0.5% total error across –40°C to +125°C - sufficient for 8- to 10-bit ADC references and sensor biasing in non-military applications.

Is LP2950-03BZ TR still in active production, and what is its lifecycle status?

LP2950-03BZ TR was discontinued by Micrel in September 2007, with end-of-life buy-through December 31, 2007. It is now a legacy part supplied by Aetrix Electronics from verified, traceable inventory. While no longer manufactured, its TO-92 packaging and mature silicon process ensure long-term reliability in existing designs, and Aetrix provides full lifecycle coordination including obsolescence forecasting and last-time-buy support.

How does the quiescent current of LP2950-03BZ TR behave in dropout condition?

The quiescent current of LP2950-03BZ TR increases only slightly in dropout - remaining near 75µA typical even when VIN approaches VOUT + dropout voltage. This behavior is explicitly designed to prolong battery life in low-input-voltage scenarios, distinguishing it from many LDOs whose IQ rises sharply near dropout. At 100mA load and VIN = 5.4V (just above dropout), measured IQ remains ≤100µA, enabling extended operation during battery depletion.