Diodes Incorporated AP1084D33L-13

Overview

AP1084D33L-13 from Diodes Incorporated is a 5A low-dropout linear regulator in TO252-3L package, fixed 3.3V output, with 1.4V max dropout at full load, ±1% initial output tolerance, and integrated thermal shutdown and current limiting. It delivers stable 3.3V/5A power for high-speed bus termination and VGA card logic supplies with input range of 4.8–12V.

For engineers reviewing the AP1084D33L-13 datasheet, AP1084D33L-13 pinout, AP1084D33L-13 application, or AP1084D33L-13 equivalent, key selection criteria include dropout voltage under 5A load, thermal resistance (θJA = 73°C/W), minimum 10µF output capacitance requirement, and fixed-mode GND-connected ADJ pin configuration.

Technical Context

The AP1084D33L-13 operates as a fixed-output LDO with internal 1.25V reference and precision error amplifier. Its control loop maintains regulation with ≤1.4V VIN–VOUT differential across 0–5A load and supports fast transient response via external 100µF output capacitor (ESR 0.15–20Ω).

Thermal protection activates at 150°C junction temperature, and current limiting triggers at ≥5.1A. The device uses a single NPN pass transistor architecture with built-in foldback current limiting and no need for external compensation components.

Key Specifications

Pinout & Package

AP1084D33L-13 uses the TO252-3L (DPAK) surface-mount package with exposed thermal tab electrically connected to VOUT. The tab must be soldered to a large copper pour for thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1084K33L-13, the AP1084D33L-13 trades thermal margin for smaller footprint and lower assembly cost; versus TLV1117-33CDCYR, it delivers 6.25× higher current with integrated fault protection essential for industrial bus and graphics applications.

Availability

AP1084D33L-13 is available at Aetrix Electronics and suitable for high-speed bus termination, VGA card logic supply, and industrial PLC I/O modules requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for AP1084D33L-13 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 power management, signal integrity, and protection devices for industrial, computing, and consumer markets.

The AP1084 series belongs to Diodes' high-current LDO portfolio, engineered specifically for low-voltage, high-current logic rails in graphics, networking, and embedded systems where dropout, thermal behavior, and transient response are critical.

FAQ

Is AP1084D33L-13 pin-compatible with adjustable AP1084 variants?

No - AP1084D33L-13 has the ADJ pin internally grounded for fixed 3.3V operation, while adjustable versions require external resistor dividers. Pin 1 is GND, not ADJ, so direct substitution would cause incorrect output voltage or instability. External resistor networks must be omitted in fixed-mode designs.

What is the minimum output capacitance required for stability?

A minimum 10µF aluminum electrolytic capacitor with ESR between 0.15Ω and 20Ω is required at the VOUT pin for guaranteed stability and optimal transient response. Tantalum or polymer capacitors meeting this ESR range are also acceptable; ceramic-only solutions are not validated and may cause oscillation.

Can AP1084D33L-13 operate from a 5V input supplying 3.3V/5A?

Yes - with 5V input, the 1.4V dropout leaves only 0.3V headroom, resulting in 1.5W power dissipation (0.3V × 5A). This is thermally feasible with the TO252-3L package on a 2oz copper plane (θJA = 73°C/W), yielding ~110°C junction rise above 25°C ambient - within the 125°C operating limit.

Does AP1084D33L-13 support reverse polarity protection?

No - the device lacks internal reverse-battery or reverse-voltage protection. Applying reversed input voltage will forward-bias the substrate diode between VIN and VOUT, potentially causing destructive current flow. An external series Schottky diode or ideal diode controller is required for reverse-polarity resilience.