Diodes Incorporated AZ1085S-2.5TRE1

Overview

AZ1085S-2.5TRE1 from BCD Semiconductor Manufacturing Limited is a fixed-output 2.5V, 3A low dropout linear regulator in TO-263-3 package with 1.3V typical dropout at full load, on-chip thermal shutdown, and ±1% output voltage accuracy over temperature and load. It delivers stable microprocessor core power in motherboards and post-regulates switching supply rails in telecom equipment.

For engineers reviewing the AZ1085S-2.5TRE1 datasheet, AZ1085S-2.5TRE1 pinout, AZ1085S-2.5TRE1 application, or AZ1085S-2.5TRE1 equivalent, key selection factors include dropout voltage at 3A, thermal resistance (θ_JC = 4.15°C/W), load regulation (≤15 mV), and compatibility with standard PCB thermal pads for TO-263-3 mounting.

Technical Context

The AZ1085S-2.5TRE1 integrates a bandgap reference, current-limit circuit (4.5A), and thermal protection to maintain safe operation under overload or high ambient conditions. Its fixed 2.5V output eliminates external resistor networks, simplifying layout while ensuring tight regulation (±1%) across 0–125°C junction temperature.

Designed for high-current linear regulation, it operates with input voltages from 4.0V to 7V and maintains <0.1% load regulation and 0.5 mV line regulation-critical for noise-sensitive analog and digital subsystems requiring clean, stable DC rails.

Key Specifications

Pinout & Package

Package: TO-263-3 (D²PAK), surface-mount, thermally enhanced with exposed tab connected to output pin. Requires minimum 250 mm² copper pour (2 oz) under tab for rated 3A performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM1085IT-2.5/NOPB, AZ1085S-2.5TRE1 offers lower dropout and RoHS-compliant packaging; versus AP1185-2.5SG-13, it provides higher PSRR (72dB vs. 65dB) and tighter initial output tolerance (±1% vs. ±2%), favoring noise-sensitive signal chains.

Availability

AZ1085S-2.5TRE1 is available at Aetrix Electronics and suitable for motherboard power supplies, telecom line cards, and DVD player power modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for AZ1085S-2.5TRE1 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

BCD Semiconductor Manufacturing Limited is a Shanghai-based analog IC foundry and fabless designer specializing in high-voltage, high-current power management devices for industrial and consumer markets.

The AZ1085 series targets cost-effective, thermally robust linear regulation in space-constrained applications-designed specifically for post-regulation, microprocessor core supply, and legacy system upgrades where simplicity and reliability outweigh ultra-low IQ demands.

FAQ

What is the minimum input voltage required for AZ1085S-2.5TRE1 to regulate at 3A?

The minimum input voltage is 3.8V: calculated as V_OUT + V_DROP(max) = 2.5V + 1.5V = 4.0V, but datasheet specifies 4.0V ≤ V_IN ≤ 7V for full 3A operation at 2.5V output. At 3.8V input, regulation holds down to ~2.7A due to dropout headroom reduction.

Can AZ1085S-2.5TRE1 be used with ceramic output capacitors?

Yes-AZ1085S-2.5TRE1 is stable with 22µF X7R ceramic capacitors (ESR ≥ 5mΩ). Unlike older LDOs, it does not require minimum ESR or tantalum types, enabling smaller footprint and higher reliability in consumer and telecom applications.

How does thermal shutdown behave during sustained overload?

Thermal shutdown activates at ~150°C junction temperature, disabling output until die cools to ~135°C. Recovery is automatic with no latch; duty cycle depends on PCB thermal mass and airflow. For continuous 3A operation, ≥250 mm² 2-oz copper under the tab is mandatory.

Is the TO-263-3 package pin-compatible with TO-220-3 versions of AZ1085?

No-pin order differs: TO-263-3 uses INPUT–OUTPUT–GND (1–2–3), while TO-220-3 uses INPUT–OUTPUT–ADJ/GND (1–2–3) with ADJ/GND on pin 3. Layouts are not interchangeable; TO-263-3's output-connected tab also requires different thermal pad routing.