Diodes Incorporated AP1186T5-G-U

Overview

AP1186T5-G-U from Diodes Incorporated is a 1.5A ultra-low dropout positive voltage regulator in TO220-5L package, configurable as adjustable or fixed-output (1.5V/1.8V/2.5V/3.3V/5.0V), with 0.26V typical dropout at 1.5A and built-in thermal shutdown and current limiting. It delivers stable 2.5V/1.5A supply to GPU core rails on ATX-based motherboards.

For engineers reviewing the AP1186T5-G-U datasheet, AP1186T5-G-U pinout, AP1186T5-G-U application, or AP1186T5-G-U equivalent, key selection criteria include remote sensing capability (Vsense pin), dual-input control architecture (Vctrl > Vin > Vout), fast transient response for GPU load steps, and minimum 100µF output capacitance requirement for stability.

Technical Context

The AP1186T5-G-U implements an NPN-based pass transistor controlled via dedicated Vctrl pin-enabling regulation with Vin as low as Vout + 0.26V while maintaining full 1.5A output. Its separate Vsense and Vout pins support true remote sensing to compensate for PCB trace IR drop at high-current loads.

It uses internal 1.25V reference with ±2.5% tolerance (1.225–1.275V) and achieves 60–70dB ripple rejection at 120Hz. Load regulation is 12–50mV across 0–1.5A, and line regulation is ≤1% over input range, meeting tight GPU core voltage tolerances including transient excursions.

Key Specifications

Pinout & Package

AP1186T5-G-U is housed in a TO220-5L thermally enhanced through-hole package with exposed tab electrically connected to Vout. The tab must be mounted to a heatsink or copper pour for thermal management.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-dropout linear regulator applications.

Compared with AP1186K5-G-U, the T5 variant offers easier manual assembly and higher thermal mass; versus LT1963AEST-2.5, it trades slightly higher dropout for superior remote sensing and dual-rail flexibility in ATX environments.

Availability

AP1186T5-G-U is available at Aetrix Electronics and suitable for GPU power delivery, ATX motherboard auxiliary rails, industrial FPGA I/O supplies, and medical imaging sensor biasing requiring stable component supply with lead-free compliance and long-lifecycle support.

Supply support for AP1186T5-G-U 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 company specializing in discrete, analog, and mixed-signal ICs, with emphasis on power management, signal integrity, and protection solutions for computing, industrial, and consumer markets.

The AP1186 belongs to Diodes' high-current LDO family engineered specifically for graphics-intensive computing platforms requiring sub-3V core rails with fast transient response and remote sensing-addressing limitations of legacy PNP-based regulators.

FAQ

What is the minimum required output capacitance for AP1186T5-G-U stability?

The AP1186T5-G-U requires a minimum 100µF aluminum electrolytic capacitor at the Vout pin to ensure loop stability and adequate transient response. This value assumes typical ESR of 50–100mΩ; using lower-ESR ceramics without series resistance may cause oscillation. The datasheet confirms 100µF meets all stability criteria across temperature and load conditions.

Can AP1186T5-G-U operate with Vin equal to Vout?

No. AP1186T5-G-U requires Vin ≥ Vout + 0.26V (typ.) to maintain regulation at 1.5A. At zero load, dropout drops to ~0.15V, but the device ceases regulation if Vin falls below Vout plus the specified dropout voltage under actual load. The Vctrl pin must also remain ≥ Vin + 1V for proper NPN base drive.

How does the Vsense pin improve regulation accuracy?

The Vsense pin enables true remote sensing by measuring voltage directly at the load instead of at the Vout pin. This compensates for voltage drop across PCB traces and connectors between the regulator and load. With Vsense tied to the load's ground-referenced node, the IC adjusts Vout to maintain 1.25V between Vsense and Adj, achieving <1% total regulation error even with 100mΩ interconnect resistance.

Is AP1186T5-G-U RoHS-compliant and lead-free?

Yes. AP1186T5-G-U carries the "-G" suffix indicating lead-free finish and RoHS compliance per EU Directive Annex Notes 5 and 7, with exemptions for glass and high-temperature solder. The "-U" suffix denotes tube packaging. Diodes Incorporated certifies full compliance with RoHS revision 13.2.2003 and provides material declarations upon request.