onsemi MC78L12ACPRP

Overview

MC78L12ACPRP from onsemi is a 12 V, 100 mA fixed-output positive linear voltage regulator in TO-92 package with internal short-circuit and thermal overload protection. It delivers stable DC power for low-current analog circuits, microcontroller peripherals, and sensor interfaces where input-to-output differential ≥2.0 V is maintained. Typical dropout voltage is 1.7 V at 25°C.

For engineers reviewing the MC78L12ACPRP datasheet, pinout, applications, or equivalent options, this page provides verified electrical specs, thermal behavior, real-world use cases, and validated alternative parts - all aligned to the official ON Semiconductor MC78L00A Series datasheet Rev. 18 (October 2016).

Technical Context

The MC78L12ACPRP uses a monolithic silicon design with built-in current limiting and thermal shutdown circuitry, eliminating need for external protection components. Its output voltage is trimmed to ±4.2% over 0°C to +125°C operating junction temperature range.

It operates with no external capacitors required in basic configurations but benefits from 0.33 µF input and 0.1 µF output bypass capacitors for improved transient response and stability under long trace or high-capacitive load conditions.

Key Specifications

Pinout & Package

MC78L12ACPRP is housed in a Pb-free TO-92 plastic package (Case 029), with straight leads and tape-and-reel packaging (2000 units/reel). Thermal resistance is 200 °C/W (Junction-to-Ambient); maximum junction temperature is +150°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC78L12ACPREG and LM78L12ACZ, the MC78L12ACPRP offers identical core regulation performance with ammo-pack delivery optimized for low-volume prototyping and repair, while retaining full compatibility with legacy 78L12 footprints and thermal management practices.

Availability

MC78L12ACPRP is available at Aetrix Electronics and suitable for industrial sensor interfaces, microcontroller peripheral rails, and legacy instrumentation power supplies requiring stable component supply, consistent TO-92 form factor, and long-term obsolescence support.

Supply support for MC78L12ACPRP 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier delivering energy-efficient, high-performance silicon solutions for automotive, industrial, cloud, medical, and IoT applications.

The MC78L00A Series was designed specifically for cost-sensitive, low-power linear regulation tasks - prioritizing ruggedness (internal thermal/short-circuit protection), minimal external component count, and broad temperature range operation (0°C to +125°C).

FAQ

What is the maximum input voltage rating for MC78L12ACPRP?

The absolute maximum input voltage for MC78L12ACPRP is 40 V DC, as specified in the Absolute Maximum Ratings table. However, for reliable operation at full 100 mA load and 125°C junction temperature, the recommended maximum continuous input is 27 V - beyond which power dissipation exceeds safe limits in the TO-92 package. Always maintain ≥2.0 V headroom above 12 V output to ensure regulation.

Does MC78L12ACPRP require input and output capacitors?

MC78L12ACPRP does not require external capacitors for basic regulation, but ON Semiconductor recommends a 0.33 µF input bypass capacitor (tantalum or ceramic) when connected via long traces to the power source, and a 0.1 µF output capacitor to improve transient response. These values are validated in Figure 2 of the MC78L00A Series datasheet and apply directly to MC78L12ACPRP.

What is the operating temperature range of MC78L12ACPRP?

MC78L12ACPRP is rated for an operating junction temperature range of 0°C to +125°C, per the "MC78LXXAC" designation in the ordering information. This corresponds to ambient temperatures up to +125°C only when power dissipation remains within thermal limits - typically requiring derating above +50°C ambient due to its 200 °C/W TO-92 thermal resistance.

Is MC78L12ACPRP pin-compatible with other 78L12 variants?

Yes - MC78L12ACPRP uses the standard TO-92 pinout (Pin 1 = V_OUT, Pin 2 = GND, Pin 3 = V_IN) shared across all MC78L12x and LM78L12 devices in the same package. This enables direct mechanical and electrical replacement in existing designs, provided thermal and electrical specifications (e.g., dropout, ripple rejection) meet system requirements.

How does MC78L12ACPRP handle thermal overload?

MC78L12ACPRP incorporates internal thermal shutdown that activates when junction temperature reaches approximately +150°C. Once triggered, the output is disabled until the die cools below the hysteresis threshold (~135°C), enabling automatic recovery without external intervention. This behavior is inherent to the monolithic design and is guaranteed across the full 0°C to +125°C operating range for MC78L12ACPRP.