Diodes Incorporated AP1086D33L-13

Overview

AP1086D33L-13 from Diodes Incorporated is a fixed-output 3.3V, 1.5A low dropout linear regulator in TO252-3L package with 1.4V max dropout at full load, ±1% output voltage tolerance, and integrated thermal shutdown. It delivers stable power for high-speed bus termination and low-current 3.3V logic supplies in VGA cards and embedded system rails.

For engineers reviewing the AP1086D33L-13 datasheet, AP1086D33L-13 pinout, AP1086D33L-13 application, or AP1086D33L-13 equivalent, key selection criteria include dropout voltage under 1.4V at 1.5A, guaranteed load regulation ≤33mV across 0–1.5A, thermal resistance θ_JA = 101°C/W (no heatsink), and mandatory 10µF minimum output capacitance for stability.

Technical Context

The AP1086D33L-13 operates as a three-terminal fixed-mode LDO regulator with internal reference (1.25V) and error amplifier driving a PNP pass transistor. Its architecture enables fast transient response to load steps up to 1.5A while maintaining output deviation within ±33mV under full-load regulation conditions.

It requires no external feedback resistors-output is factory-trimmed to 3.3V with ±1% initial accuracy-and relies on a single 10µF minimum aluminum electrolytic capacitor at VOUT for frequency compensation and stability across temperature and load.

Key Specifications

Pinout & Package

AP1086D33L-13 uses the TO252-3L (DPAK) surface-mount package with exposed thermal pad connected internally to VOUT. The tab is electrically tied to Pin 2 (VOUT) and must be soldered to a thermal plane for effective heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1086K33L-13, the D33L-13 offers identical electrical performance but trades thermal efficiency for smaller footprint; versus LD1117S33TR, it delivers 50% higher current, tighter voltage accuracy, and lower dropout-making it preferable for demanding FPGA or graphics applications.

Availability

AP1086D33L-13 is available at Aetrix Electronics and suitable for VGA graphics cards, FPGA I/O banks, industrial PLC modules, and embedded LAN PHY designs requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for AP1086D33L-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 AP1086 product line delivers high-current, low-dropout linear regulators optimized for precision voltage regulation in space- and thermally-constrained embedded systems where switching noise must be avoided.

FAQ

What is the minimum input voltage required for AP1086D33L-13 to regulate at full 1.5A load?

The device requires VIN ≥ VOUT + 1.4V = 4.7V to maintain regulation at 1.5A. Below this differential, output voltage drops linearly with input-verified by dropout voltage test data showing 1.3V typical and 1.4V max at full load. Input below 4.7V results in unregulated operation regardless of load current.

Can AP1086D33L-13 be used in adjustable mode?

No-AP1086D33L-13 is a fixed 3.3V variant. Only the "Adj" version (e.g., AP1086DxxL-13 with blank suffix) supports external resistor programming. This part has internal trimming for 3.3V and ties Pin 1 (Adj/GND) directly to system ground; connecting external resistors will disrupt regulation.

Is a heatsink required for continuous 1.5A operation at 70°C ambient?

At 70°C ambient and 1.5A load with 5V input, power dissipation is (5V − 3.3V) × 1.5A = 2.55W. With θ_JA = 101°C/W, junction temperature rises to 70°C + (2.55W × 101°C/W) ≈ 328°C-far exceeding 150°C max. A heatsink or copper pour is mandatory; design must limit power or reduce ambient to ensure T_J ≤ 125°C for reliability.

What type and value of output capacitor is mandatory for stability?

A minimum 10µF aluminum electrolytic capacitor is required between VOUT and GND, as specified in the datasheet's stability section. Tantalum or polymer capacitors may be used if ESR is 0.1–1Ω; ceramic capacitors alone are insufficient due to near-zero ESR causing phase-margin loss. The capacitor must be placed within 5mm of the VOUT pin per layout guidelines.