Diodes Incorporated AP78L05VL-A

Overview

AP78L05VL-A from Diodes Incorporated is a fixed-output +5.0V, 100mA three-terminal positive linear voltage regulator in TO92 package with ±5% output tolerance, internal thermal overload protection, and short-circuit current limiting. It delivers stable local regulation for logic supplies in consumer audio, optical drives, and set-top boxes without external components.

For engineers reviewing the AP78L05VL-A datasheet, AP78L05VL-A pinout, AP78L05VL-A application, or AP78L05VL-A equivalent, this page provides verified specifications, package-validated pin functions, real-world use cases, and validated alternative parts for design-in and BOM optimization.

Technical Context

The AP78L05VL-A implements a monolithic series-pass transistor regulator architecture with built-in safe-area protection that reduces short-circuit current as pass transistor V_CE increases. Its thermal shutdown activates at T_J = 150°C, and internal current limiting caps peak output at 140mA.

It operates across -20°C to +85°C ambient with input voltage range 7–20V, dropout voltage ≤2.0V at I_OUT = 40mA, and ripple rejection ≥47dB at 120Hz. Output noise is 40µV RMS (10Hz–100kHz), and quiescent current remains ≤5mA over full load and temperature range.

Key Specifications

Pinout & Package

AP78L05VL-A uses the industry-standard plastic TO92 package (3-pin, through-hole), lead-free per RoHS Directive 2002/95/EC. Pinout is validated per Diodes Inc. DS31054 Rev. 10–2, bottom-view orientation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM78L05ACZ and MC78L05ACP, AP78L05VL-A offers superior thermal safety (documented 150°C shutdown), lower noise (40µV vs ≥65µV), and guaranteed RoHS compliance - making it optimal for new consumer electronics designs requiring reliability and regulatory alignment.

Availability

AP78L05VL-A is available at Aetrix Electronics and suitable for CD-ROM drive power, DVD player logic supply, and set-top box tuner module applications requiring stable component supply, RoHS compliance, and long-term manufacturability.

Supply support for AP78L05VL-A 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, headquartered in Plano, Texas, with design centers across Asia and manufacturing in China, Taiwan, and the US.

The AP78LXX series was designed specifically for cost-sensitive consumer electronics requiring robust, self-protected, fixed-output linear regulation in legacy-compatible packages like TO92 and SOT89.

FAQ

What is the minimum input voltage required for AP78L05VL-A to maintain regulation?

The AP78L05VL-A requires a minimum input voltage of 6.7V to sustain line regulation at 25°C, increasing slightly with temperature. Below this threshold, output voltage drops linearly with input; datasheet specifies 7V as recommended minimum for full-spec operation across -20°C to +85°C ambient.

Can AP78L05VL-A be used without an output capacitor?

No - a minimum 0.1µF ceramic capacitor is required at VOUT to ensure stability and suppress high-frequency noise, per Diodes Inc. DS31054 Section "Typical Application Circuit". Omitting it risks oscillation and degraded ripple rejection, especially with long PCB traces or inductive loads.

How does the safe-area protection function during a short-circuit event?

During output short-circuit, the AP78L05VL-A's safe-area protection reduces output current as the pass transistor's V_CE rises, limiting internal power dissipation. This prevents second breakdown and allows indefinite short-circuit survival at room temperature, provided junction temperature stays below 150°C.

Is AP78L05VL-A pin-compatible with older AP78L05 variants in TO92?

Yes - AP78L05VL-A shares identical TO92 pinout (VIN-GND-VOUT, bottom view), mechanical dimensions, and electrical specs with prior AP78L05 versions. The "VL-A" suffix denotes lead-free TO92 packaging and tape-and-reel shipping; all functional behavior matches the base AP78L05 specification.