onsemi MC79L05ACDG

Overview

MC79L05ACDG from ON Semiconductor is a 100 mA negative fixed-voltage linear regulator delivering −5.0 V output with ±4% tolerance (−4.8 V to −5.2 V) at +25°C, featuring internal thermal shutdown and short-circuit current limiting in an SOIC-8 package. It operates across 0°C to +125°C junction temperature range and requires no external components for basic regulation in low-power analog or digital subsystems.

For engineers reviewing the MC79L05ACDG datasheet, pinout, applications, or equivalent options, key selection criteria include dropout voltage (1.7 V at 40 mA), ripple rejection (41–49 dB at 120 Hz), input bias current (6.0 mA max at +25°C), and SOIC-8 thermal resistance (180°C/W junction-to-ambient).

Technical Context

The MC79L05ACDG implements a monolithic bipolar linear regulator architecture with built-in thermal overload protection and foldback current limiting. Its internal circuitry maintains stable −5.0 V output under load currents from 1.0 mA to 100 mA and input voltages from −7.0 V to −20 V (for specified line regulation).

Designed for fixed negative rail generation, it uses a ground-referenced feedback structure with no external sense path-requiring careful PCB layout to minimize ground impedance. Input bypassing with ≥0.33 µF and output stabilization with ≥0.1 µF capacitors are recommended for transient response and stability across operating conditions.

Key Specifications

Pinout & Package

MC79L05ACDG is housed in a Pb-free SOIC-8 (Case 751) package with 1.27 mm pitch, 5.0 mm × 4.0 mm body, and 1.75 mm max height. Thermal pad not present; standard JEDEC SOIC footprint applies.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM79L05ACM/NOPB, MC79L05ACDG offers superior 49 dB ripple rejection but narrower −20 V input limit; versus MC79L05ACPG, it provides identical regulation performance in a smaller SOIC-8 footprint with slightly higher thermal resistance-favoring compact, automated production environments.

Availability

MC79L05ACDG is available at Aetrix Electronics and suitable for industrial sensor conditioning, RS-232 interface design, and microcontroller peripheral power applications requiring stable component supply, RoHS compliance, and SOIC-8 surface-mount compatibility.

Supply support for MC79L05ACDG 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

ON Semiconductor is a global semiconductor manufacturer specializing in power management, analog, sensors, and logic devices for automotive, industrial, and cloud power applications.

The MC79L00A Series was developed to provide cost-effective, thermally robust negative voltage regulation for on-card and distributed power needs in space- and reliability-constrained systems.

FAQ

What is the maximum input voltage for MC79L05ACDG under standard operating conditions?

The MC79L05ACDG supports a maximum input voltage of −20 Vdc when measuring line regulation per datasheet test conditions (−7.0 Vdc ≥ VI ≥ −20 Vdc). Exceeding −20 Vdc may degrade regulation accuracy or trigger internal protection. For applications requiring higher input, consult the MC79L05ABDG variant rated to −35 Vdc input.

Does MC79L05ACDG require input and output capacitors for stable operation?

Yes, MC79L05ACDG recommends a 0.33 µF input bypass capacitor and a 0.1 µF output capacitor for optimal stability and transient response. These values are specified in the datasheet's Figure 3 and Applications Information section. Omission may cause oscillation or poor ripple rejection, especially with long input traces or large load capacitance.

What is the thermal shutdown threshold of MC79L05ACDG?

The MC79L05ACDG activates internal thermal shutdown at a junction temperature of +150°C, as defined in the Maximum Ratings table. Recovery occurs once junction temperature falls below the hysteresis threshold (~135°C), allowing automatic resumption of regulation without external intervention.

Can MC79L05ACDG be used in automotive applications?

The MC79L05ACDG is rated for 0°C to +125°C junction temperature, making it suitable for under-hood or cabin electronics where ambient temperatures remain within this range. However, it is not qualified to AEC-Q100 standards; for automotive-grade assurance, consider the MC79L05ABDG variant with −40°C to +125°C operation and extended qualification testing.

How does the SOIC-8 pin configuration of MC79L05ACDG differ from TO-92 versions?

The MC79L05ACDG SOIC-8 has four dedicated input pins (Pins 2, 3, 6, 7), one ground (Pin 5), one output (Pin 1), and two NCs (Pins 4, 8)-enabling low-inductance, high-current input routing. In contrast, the TO-92 version (e.g., MC79L05ACPG) uses three pins: Input, Ground, Output-with no redundant terminals or NCs.