Diodes Incorporated AP1184K5-25L-13

Overview

AP1184K5-25L-13 from Diodes Incorporated is a 4A ultra-low dropout positive voltage regulator in TO263-5L package, configured for fixed 2.5V output. It delivers 2.5V at up to 4A with 0.85V maximum dropout (Vin–Vout) at full load, built-in thermal shutdown and current limiting, and remote sensing via Vsense pin for precise load regulation-used in GPU core power delivery from 3.3V ATX rails.

For engineers reviewing the AP1184K5-25L-13 datasheet, AP1184K5-25L-13 pinout, AP1184K5-25L-13 application, or AP1184K5-25L-13 equivalent, key selection criteria include dropout voltage under 4A load, remote sense capability, Vctrl pin biasing requirements, and TO263-5L thermal performance with copper pad layout per AP02001.

Technical Context

The AP1184K5-25L-13 operates as a fixed-mode NPN-based LDO with separate Vctrl and Vsense pins: Vctrl (≥2.75V above Vout) supplies base drive to the pass transistor, enabling lower dropout than conventional PNP regulators; Vsense provides true remote feedback, compensating for PCB trace IR drop between Vout and load.

It integrates thermal shutdown (trip at ~150°C) and current limit (~4.2A), supports fast transient response (<500ns load step recovery), and requires minimum 100µF output capacitance with ESR 50–100mΩ for stability-optimized for graphics chipset core supply where tight initial tolerance (±1%) and low load regulation (20–25mV over 0–4A) are critical.

Key Specifications

Pinout & Package

AP1184K5-25L-13 uses the TO263-5L surface-mount package with exposed tab electrically connected to Vout for thermal conduction and output return path. Pad layout must follow Diodes Inc. AP02001 guidelines (2oz copper, minimum 1.4"×1.4" area).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1184K5-25L-13, AP1186K5-25L-13 offers higher current headroom and lower dropout at cost of thermal density, while TPS7A8300RGRT simplifies supply architecture but sacrifices remote sensing precision and requires tighter input voltage control.

Availability

AP1184K5-25L-13 is available at Aetrix Electronics and suitable for GPU core power supply, ATX-based embedded system rails, and low-voltage ASIC biasing requiring stable component supply with lead-free compliance and TO263-5L thermal performance.

Supply support for AP1184K5-25L-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 high-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The AP1184 product line targets high-current, ultra-low-dropout linear regulation in multi-rail systems-designed specifically for graphics and processor core supplies where efficiency, accuracy, and transient response outweigh switching complexity.

FAQ

What is the minimum required Vctrl voltage for AP1184K5-25L-13?

Vctrl must be at least 2.75V above the output voltage (i.e., ≥5.25V for 2.5V output) to ensure proper base drive to the NPN pass transistor. This requirement is specified in the Electrical Characteristics table under "Dropout Voltage (Vctrl–Vout)" test conditions and is critical for maintaining regulation under full 4A load.

Can AP1184K5-25L-13 be used without remote sensing?

Yes-Vsense can be shorted directly to Vout for local regulation, though this forfeits the <25mV load regulation benefit. The device remains functional, but voltage accuracy at the load will degrade proportionally to PCB trace resistance (e.g., 10mΩ × 4A = 40mV error). Remote sensing is recommended for GPU or FPGA applications where load-point accuracy is mandatory.

Why does AP1184K5-25L-13 require separate Vctrl and Vin pins?

The split-input architecture isolates the control circuitry's bias supply (Vctrl) from the main power path (Vin), allowing Vctrl to be derived from a higher, more stable rail (e.g., 5V) while Vin comes from a lower, noisier rail (e.g., 3.3V ATX). This reduces dropout voltage and improves transient immunity-unlike single-input LDOs where control and power share the same node.

Is AP1184K5-25L-13 suitable for new designs despite "NOT RECOMMENDED FOR NEW DESIGN" in the datasheet?

No-Diodes Incorporated explicitly marks AP1184 as "NOT RECOMMENDED FOR NEW DESIGN" (Rev. 6, Oct 2014), indicating active obsolescence planning. While fully functional and supported for legacy repair or continuity, new designs should consider AP1186 (pin-compatible 5A upgrade) or modern alternatives like TPS7A8300 with enhanced features and active lifecycle status.