onsemi MC78L08ABDR2

Overview

MC78L08ABDR2 from onsemi is a 100 mA, fixed +8.0 V positive linear voltage regulator in SOIC-8 package, featuring internal short-circuit current limiting, thermal shutdown, and dropout voltage of 1.7 V at 25°C. It operates across −40°C to +125°C and requires no external components for basic regulation in low-power embedded power rails, sensor interfaces, and industrial control modules.

For engineers reviewing the MC78L08ABDR2 datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed output voltage tolerance (±3% at 25°C), load regulation (≤40 mV over 1–40 mA), ripple rejection (min 37 dB at 120 Hz), thermal resistance (R_JA ≈ 120–150°C/W depending on PCB copper area), and automotive-grade temperature range compliance.

Technical Context

The MC78L08ABDR2 implements a monolithic series-pass transistor regulator with built-in protection circuitry: current-limiting folds back under overload, and thermal shutdown activates at ~150°C junction temperature. Its architecture eliminates need for external compensation capacitors in most applications, though input bypass (≥0.33 µF) and output decoupling (≥0.1 µF) are recommended for transient stability.

It delivers regulated +8.0 V output with line regulation ≤125 mV (11–23 V input range) and load regulation ≤40 mV (1–40 mA load). Dropout voltage remains constant at 1.7 V across temperature and load, enabling reliable operation in margin-constrained 9–10 V input systems.

Key Specifications

Pinout & Package

MC78L08ABDR2 uses an 8-pin SOIC-8 (Case 751) package with pins 2, 3, 6, and 7 internally connected to the die attach flag for enhanced thermal conduction. The device has three functional terminals: Input (Pin 4), Output (Pin 1), and Ground (Pins 2, 3, 6, 7).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC78L08ABDR2, MC78L08ACDR2G lacks extended temperature capability and automotive qualification, while TL78L08ACDR trades guaranteed −40°C operation for alternate process characteristics and vendor-specific reliability data - both require validation for thermal derating and long-term stability in safety-critical systems.

Availability

MC78L08ABDR2 is available at Aetrix Electronics and suitable for industrial sensor nodes, automotive body control modules, legacy equipment retrofits, and medical handheld devices requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MC78L08ABDR2 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, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The MC78L00A Series was designed as a cost-effective, rugged fixed-output linear regulator family targeting space- and reliability-constrained embedded systems needing simple, self-protected DC-DC conversion without external components.

FAQ

What is the maximum input voltage rating for MC78L08ABDR2?

The MC78L08ABDR2 supports up to 35 V DC input voltage when operated at 12 V–18 V nominal input range, and up to 40 V for 24 V input configurations. Absolute maximum input voltage is 35 V for standard operation; exceeding this risks permanent damage even with thermal shutdown active. Always refer to the Absolute Maximum Ratings table in the official datasheet for safe design margins.

Does MC78L08ABDR2 require input and output capacitors for stable operation?

Yes - while the MC78L08ABDR2 does not require external compensation, a 0.33 µF input capacitor is recommended when the regulator is located more than ~5 cm from the bulk filter, and a 0.1 µF output capacitor improves transient response. These values are specified in the Standard Application schematic (Figure 2) and confirmed in the Applications Information section of the datasheet.

Is MC78L08ABDR2 pin-compatible with other SOIC-8 variants in the MC78L00A family?

Yes - all SOIC-8 versions of the MC78L00A Series (e.g., MC78L05ABDR2G, MC78L12ABDR2G) share identical pinout: Pin 1 = Output, Pins 2/3/6/7 = Ground, Pin 4 = Input, Pins 5/8 = NC. This allows direct substitution across output voltages without PCB redesign, provided thermal and electrical constraints are verified per variant.

What is the typical output noise voltage of MC78L08ABDR2?

The MC78L08ABDR2 exhibits 60 µV RMS output noise over the 10 Hz to 100 kHz bandwidth at 25°C, as measured per the Electrical Characteristics table for the MC78L08AC/AB variants. This low noise level supports precision analog circuits such as sensor signal conditioning and reference buffers where switching regulator interference must be avoided.

How does thermal performance differ between MC78L08ABDR2 (SOIC-8) and TO-92 versions like MC78L08ABPG?

MC78L08ABDR2 in SOIC-8 achieves R_JA ≈ 120–150°C/W with standard PCB copper, while MC78L08ABPG in TO-92 has R_JA = 200°C/W. This means the SOIC-8 version dissipates ~30–40% more power before reaching thermal shutdown under identical layout conditions - making it preferable for higher ambient or sustained-load applications.