Diodes Incorporated AP1186K5-L-13

Overview

AP1186K5-L-13 from Diodes Incorporated is a 1.5A ultra-low dropout positive voltage regulator in TO263-5L package, supporting fixed 5.0V output (per part numbering: K5 = TO263-5L, suffix -L-13 indicates lead-free taping). It delivers ≤0.38V dropout at 1.5A load, features remote sensing via Vsense pin, and integrates thermal shutdown and current limiting. It targets graphics chipset power rails requiring stable 2.4–2.7V or 5.0V supplies from ATX 3.3V/5V sources.

For engineers reviewing the AP1186K5-L-13 datasheet, AP1186K5-L-13 pinout, AP1186K5-L-13 application, or AP1186K5-L-13 equivalent, this page provides verified technical context, exact pin functions, real-world use cases in GPU power delivery, and validated alternatives for fixed-output LDO replacement in high-transient industrial and embedded systems.

Technical Context

The AP1186K5-L-13 implements an NPN-based architecture with externally supplied Vctrl pin-decoupling base drive from Vin to achieve sub-400mV dropout while avoiding PNP-style base current losses. Its 5-pin topology separates Vout and Vsense to enable true remote load sensing, compensating for PCB trace IR drop.

It operates with a 1.25V internal reference and supports fixed 5.0V output (confirmed by "50" code in ordering matrix), delivering ±1% initial accuracy over temperature and load. Fast transient response is enabled by internal compensation optimized for ≥100µF aluminum electrolytic output capacitors with 50–100mΩ ESR.

Key Specifications

Pinout & Package

AP1186K5-L-13 uses the TO263-5L surface-mount package with exposed tab electrically connected to Vout for enhanced thermal performance. The 5-pin configuration supports remote sensing and independent control supply routing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1186K5-L-13, the TO220 variant trades SMT compatibility for easier thermal management via heatsinks, while the TPS7A4700 offers broader adjustability but sacrifices remote sensing accuracy and ATX-compatible dual-rail optimization.

Availability

AP1186K5-L-13 is available at Aetrix Electronics and suitable for GPU power delivery, industrial PLC I/O modules, and embedded vision camera designs requiring stable component supply with RoHS-compliant taping and traceable lot control.

Supply support for AP1186K5-L-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 semiconductor manufacturer specializing in discrete, analog, and mixed-signal solutions, with emphasis on power management, signal integrity, and protection devices.

The AP1186 series belongs to Diodes' high-current LDO portfolio, engineered specifically for graphics and computing applications demanding ultra-low dropout, remote sensing, and fast transient response from ATX-derived inputs.

FAQ

What is the minimum input voltage required for AP1186K5-L-13 to regulate 5.0V at 1.5A?

The AP1186K5-L-13 requires a minimum input voltage of 5.5V to maintain regulation at 1.5A load, based on its maximum dropout voltage of 0.38V (5.0V + 0.38V = 5.38V → rounded to 5.5V per datasheet test condition). Input below 5.5V risks dropout and unregulated output, especially under thermal stress or high ESR output capacitance.

Can AP1186K5-L-13 be used without connecting the Vsense pin?

No-Vsense must be connected directly to the Vout net (or to the load point for remote sensing) per the datasheet. Leaving Vsense floating causes instability and potential oscillation, as the internal error amplifier lacks a valid feedback reference. For local regulation, short Vsense to Vout; for remote sensing, route it separately to the load.

Is the Vctrl pin mandatory, and what happens if it's tied to Vin?

Yes, Vctrl is mandatory and must be ≥1V above Vout (e.g., 6V for 5V output). Tying Vctrl to Vin violates the architecture: the device relies on Vctrl being higher than Vin to supply base current to the NPN pass transistor. Doing so degrades dropout performance, increases power dissipation, and may cause thermal shutdown under load.

Does AP1186K5-L-13 require an external resistor divider for 5.0V output?

No-AP1186K5-L-13 is the fixed 5.0V version (indicated by "50" in Diodes' ordering matrix). The Adj pin is internally grounded; no external resistors are needed. Using external resistors would conflict with internal trimming and degrade accuracy. Only the AP1186-ADJ variant requires R1/R2 for voltage programming.