Diodes Incorporated AZ1085CD-3.3TRG1

Overview

AZ1085CD-3.3TRG1 from Diodes Incorporated is a 3.3V fixed-output, 3A low-dropout linear regulator in TO252-2 (3) package, featuring 1.3V typical dropout at full load, on-chip thermal shutdown, and current limiting. It delivers stable microprocessor supply voltage with ±1% output accuracy over 0–125°C junction temperature and supports post-regulation for switching supplies.

For engineers reviewing the AZ1085CD-3.3TRG1 datasheet, AZ1085CD-3.3TRG1 pinout, AZ1085CD-3.3TRG1 application, or AZ1085CD-3.3TRG1 equivalent, key selection criteria include dropout voltage under 3A load, compatibility with low-ESR ceramic capacitors, thermal protection behavior, and TO252-2 (3) footprint compatibility with PCB layout constraints.

Technical Context

The AZ1085CD-3.3TRG1 implements a bandgap-referenced error amplifier driving a PNP pass transistor, enabling low dropout operation while maintaining tight line regulation (0.015% typ) and load regulation (0.1% typ). Its internal current limit of 4.5A and thermal shutdown activate independently to protect against overload and junction overheating.

Designed for fixed-output use, it integrates precision-adjust resistors to set VOUT = 3.3V with ±1% tolerance across temperature and load, eliminating external feedback components. The device operates from 4.8V to 8V input and maintains stability with ≥10µF ceramic output capacitance.

Key Specifications

Pinout & Package

Package: TO252-2 (3), surface-mount, thermally enhanced DPAK variant with exposed tab connected to GND for improved heat dissipation (θJA = 100°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 3.3V, 3A LDO applications.

Compared with AP2204K-3.3TRG1 and TLV1117-33CDCYR, AZ1085CD-3.3TRG1 uniquely combines 3A capability, integrated 4.5A current limiting, and TO252-2 (3) thermal performance-making it the only drop-in solution for high-current, safety-critical LDO applications requiring self-protecting operation.

Availability

AZ1085CD-3.3TRG1 is available at Aetrix Electronics and suitable for microprocessor power supplies, telecom line card biasing, battery charger post-regulation, and motherboard standby rails requiring stable component supply with long-term industrial lifecycle support.

Supply support for AZ1085CD-3.3TRG1 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 solutions for power management, signal integrity, and connectivity applications.

The AZ1085C series was designed specifically for high-current, low-noise linear regulation in space-constrained industrial and computing systems where thermal robustness and fixed-output simplicity are essential.

FAQ

Is AZ1085CD-3.3TRG1 still in active production?

No-AZ1085CD-3.3TRG1 is marked obsolete by Diodes Incorporated as of November 2021. It remains available through Aetrix Electronics' legacy inventory and authorized distributor channels, with full traceability and documented RoHS/Green compliance per DS36735 Rev. 4. Customers are advised to transition to AZ1084C-based alternatives for new designs.

What is the maximum allowable input voltage for AZ1085CD-3.3TRG1?

The absolute maximum input voltage is 13.2V, but the recommended operating range is 4.8V to 8V per the datasheet's Recommended Operating Conditions table. Exceeding 8V increases power dissipation and thermal stress without functional benefit for the 3.3V output configuration.

Can AZ1085CD-3.3TRG1 be used with tantalum output capacitors?

Yes, but ceramic capacitors are strongly preferred. The device is optimized for low-ESR ceramics (≥10µF X5R/X7R); tantalum capacitors may cause instability due to higher ESR and aging effects. If used, minimum ESR must be ≤50mΩ and capacitance ≥22µF to meet phase margin requirements.

Does the ADJ/GND pin require an external capacitor for stability?

No-on fixed-output variants like AZ1085CD-3.3TRG1, the ADJ/GND pin is internally connected to ground and does not require external compensation. It serves solely as the GND reference and thermal pad connection point; no capacitor or resistor network is needed at this terminal.