Diodes Incorporated AP1084KG-13

Overview

AP1084KG-13 from Diodes Incorporated is a 5A low-dropout positive voltage regulator available in fixed 3.3V output mode, housed in a TO263-3L surface-mount package with thermal tab connected to VOUT. It delivers ≤1.4V dropout at full 5A load, features built-in thermal shutdown and current limiting, and maintains tight output regulation (±1.5% initial tolerance, ±1% load regulation) for stable 3.3V supply in high-current digital logic and bus termination applications.

For engineers reviewing the AP1084KG-13 datasheet, AP1084KG-13 pinout, AP1084KG-13 application, or AP1084KG-13 equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, confirmed alternative parts with functional differences, and supply support for industrial power rail deployment.

Technical Context

The AP1084KG-13 operates as a fixed-output linear regulator with internal 1.25V reference and error amplifier driving an NPN pass transistor. Its feedback loop is internally configured for 3.3V output, eliminating external resistors-pin 1 (Adj/GND) serves only as ground return in fixed mode.

It employs thermal foldback current limiting and junction temperature sensing to activate shutdown at 150°C. The TO263-3L package provides 60°C/W junction-to-ambient thermal resistance under standard PCB layout, enabling 5A continuous operation with appropriate copper area and airflow.

Key Specifications

Pinout & Package

AP1084KG-13 uses the TO263-3L (D²PAK) thermally enhanced surface-mount package. The exposed metal tab is electrically connected to VOUT and serves as primary heat path. Package dimensions: 10.29 × 9.65 × 4.83 mm (L × W × H), with 2.54 mm lead pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1084KG-13, AP1084KT3G offers identical electrical performance but higher thermal resistance and through-hole mounting, while TLV1117-33CDCYR is fundamentally undersized for 5A applications-neither is a drop-in replacement without thermal or current derating.

Availability

AP1084KG-13 is available at Aetrix Electronics and suitable for industrial control systems, embedded networking equipment, and medical imaging interfaces requiring stable component supply with long-term lifecycle assurance.

Supply support for AP1084KG-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, headquartered in Plano, Texas, with design centers across Asia and manufacturing in China, Malaysia, and Taiwan.

The AP1084 product line targets high-current, low-noise linear regulation for digital logic and bus termination, emphasizing thermal robustness, fast transient response, and simplified fixed-voltage implementation in space-constrained industrial and computing platforms.

FAQ

What is the minimum input voltage required for AP1084KG-13 to regulate 3.3V at 5A?

The AP1084KG-13 requires VIN ≥ VOUT + 1.4V = 4.7V to maintain regulation at full 5A load. At lower currents, dropout decreases-e.g., 1.3V at 2A-so 4.6V input may suffice for partial-load operation, but 4.7V is the guaranteed minimum for full-rated output.

Can AP1084KG-13 be used in adjustable mode?

No. The "K" suffix denotes TO263-3L package, and "G" indicates green/halogen-free, but the "-13" tape-and-reel packaging and part number structure confirm fixed 3.3V output (33 code). Adjustable versions use blank suffix (e.g., AP1084KG-13 is not valid; AP1084K-13 would be adjustable). This device has internal feedback and cannot be reconfigured.

Is a heatsink mandatory for AP1084KG-13 at 5A continuous load?

Yes. With θ_JA = 60°C/W and P_D = (VIN − 3.3V) × 5A, even at VIN = 5V, power dissipation is 8.5W-raising junction temperature by 510°C above ambient without heatsinking. A 10 cm² 2oz copper pour plus optional finned heatsink is required to keep T_J < 125°C at 25°C ambient.

Does AP1084KG-13 require an input capacitor?

Yes. While not explicitly specified in the datasheet's absolute minimums, a ≥100µF low-ESR aluminum or polymer capacitor is required at VIN to prevent input voltage sag during 5A load transients. Without it, VIN may dip below dropout threshold, causing output collapse and potential thermal stress due to repeated regulation loss.