Diodes Incorporated AS78L05MTR-G1

Overview

AS78L05MTR-G1 from Diodes Incorporated is a fixed 5V, 100mA positive linear voltage regulator in SOIC-8 package with ±5% output voltage accuracy over –40°C to +125°C, internal thermal shutdown and short-circuit current limiting, designed for local on-card regulation in microprocessor power supplies and motherboard applications.

For engineers reviewing the AS78L05MTR-G1 datasheet, AS78L05MTR-G1 pinout, AS78L05MTR-G1 application, or AS78L05MTR-G1 equivalent, key selection criteria include dropout voltage (1.7V at 40mA), PSRR (47–62dB at 120Hz), output noise (40µV RMS, 10Hz–100kHz), and SOIC-8 thermal resistance (θJC = 62°C/W).

Technical Context

The AS78L05MTR-G1 implements a monolithic three-terminal linear regulator architecture with integrated safe-area protection for the output transistor, enabling stable 5V regulation without external components. It operates across an input voltage range of 7–20V and delivers up to 100mA while maintaining output accuracy within ±5% across full temperature and load conditions.

Its internal thermal overload protection activates at 150°C junction temperature, and current limiting prevents damage during sustained short-circuit events. The SOIC-8 variant supports higher power dissipation than TO-92 or SOT-89 due to improved thermal path via exposed pad (implied by θJC = 62°C/W and package outline).

Key Specifications

Pinout & Package

AS78L05MTR-G1 is housed in an 8-pin SOIC package (body size 4.9 × 6.0 mm, lead pitch 1.27 mm) with GND pins on both sides for low-impedance return paths and thermal enhancement. Pin 1 is INPUT, Pins 2–3 and 6–7 are GND, Pin 4 is OUTPUT, and Pins 5 & 8 are NC (no connect).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM78L05ACM/NOPB and MC78L05ABDR2G, AS78L05MTR-G1 offers superior PSRR and lower output noise while matching the ±5% tolerance and safe-area protection - making it optimal for noise-sensitive digital/analog mixed-signal boards requiring long-term reliability.

Availability

AS78L05MTR-G1 is available at Aetrix Electronics and suitable for microprocessor power supplies, motherboard local regulation, industrial sensor interfaces, and legacy peripheral power applications requiring stable component supply, RoHS-compliant green packaging, and tape-and-reel delivery for automated assembly.

Supply support for AS78L05MTR-G1 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The AS78LXX series was developed as a drop-in replacement family for legacy 78Lxx regulators, emphasizing robust thermal performance, integrated protection, and compatibility across TO-92, SOT-89, and SOIC-8 footprints for flexible board design.

FAQ

What is the minimum input voltage required for AS78L05MTR-G1 to maintain regulation?

The AS78L05MTR-G1 requires a minimum input voltage of 7 V to guarantee regulation across its full operating temperature and load range (–40°C to +125°C, 1–100 mA). At 40 mA load, dropout is 1.7 V, so 6.7 V is theoretically sufficient - but 7 V is the validated minimum per datasheet test conditions and ensures margin against line sag and thermal drift.

Can AS78L05MTR-G1 replace a standard 78L05 in SOIC-8 footprint designs?

Yes - AS78L05MTR-G1 uses the same SOIC-8 pinout (Input–GND–GND–Output–NC–GND–GND–NC) and matches the electrical behavior of industry-standard 78L05 regulators, including ±5% output tolerance, 100 mA current capability, and thermal shutdown. No layout or schematic changes are needed for drop-in replacement.

Is an input capacitor required for stable operation?

Yes - the datasheet specifies a minimum 0.33 µF ceramic or tantalum input capacitor (C_IN) placed close to the INPUT and GND pins. This stabilizes the regulator against source impedance and prevents oscillation during line transients, especially when fed from long traces or switching supplies.

Does AS78L05MTR-G1 support reverse-voltage protection?

No - AS78L05MTR-G1 lacks built-in reverse-polarity protection. If the input voltage can be applied backwards (e.g., during board handling or hot-swap scenarios), an external series diode or MOSFET-based protection circuit must be added to prevent device damage, as reverse voltage exceeding –0.3 V may cause latch-up or permanent failure.