Diodes Incorporated AZ1084CS2-ADJTRG1

Overview

AZ1084CS2-ADJTRG1 from Diodes Incorporated is a 5A adjustable low-dropout linear regulator in TO252-2 (3) package, delivering stable output voltage down to 1.225V via external resistor divider, with 1.35V typical dropout at full load and integrated thermal shutdown. It serves as post-regulator for switching supplies and microprocessor core power in desktop PCs and embedded systems.

For engineers reviewing the AZ1084CS2-ADJTRG1 datasheet, AZ1084CS2-ADJTRG1 pinout, AZ1084CS2-ADJTRG1 application, or AZ1084CS2-ADJTRG1 equivalent, key selection criteria include dropout voltage at 5A, adjust pin current stability over temperature, compatibility with low-ESR ceramic capacitors, and thermal resistance (θJC = 7.36°C/W) for high-power linear regulation.

Technical Context

The AZ1084CS2-ADJTRG1 uses a trimmed bandgap reference (1.225–1.270V) and internal current-limiting circuitry to maintain regulation under transient loads up to 6.5A. Its feedback loop accepts voltage from an external resistive divider connected to the ADJ pin, enabling precise output setting across 1.225V–12V range.

Thermal protection activates when junction temperature exceeds +150°C, and operation is specified from 0°C to +125°C junction temperature. The device supports input voltages up to 12V and requires only 10μF input and 22μF output ceramic capacitance for stability.

Key Specifications

Pinout & Package

Package: TO252-2 (3), surface-mount, thermally enhanced plastic package with exposed cathode pad (Pin 2) for PCB heat transfer. Dimensions: 6.5 × 10.4 mm body, 2.2 mm height, 0.72 mm lead thickness.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar adjustable LDO regulator applications.

Compared with LT1963AES8-ADJ#PBF and TPS75733KTTT, AZ1084CS2-ADJTRG1 uniquely combines 5A output, adjustable voltage, TO252 thermal performance, and sub-1.4V dropout - making it irreplaceable in high-current, multi-rail embedded power systems requiring design reuse across voltage points.

Availability

AZ1084CS2-ADJTRG1 is available at Aetrix Electronics and suitable for desktop PC motherboard power delivery, industrial FPGA I/O regulation, and battery charger post-regulation requiring stable component supply, long-term lifecycle assurance, and RoHS 3 compliance.

Supply support for AZ1084CS2-ADJTRG1 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 AZ1084C series belongs to Diodes' high-current LDO portfolio, engineered specifically for post-regulation in hybrid power architectures where switching converter efficiency must be balanced with analog rail cleanliness and thermal manageability.

FAQ

What is the minimum required output capacitance for stable operation?

The AZ1084CS2-ADJTRG1 requires a minimum of 22µF ceramic output capacitance with ESR ≤10mΩ. This value ensures phase margin >45° across all load and input conditions. Using smaller values or higher-ESR capacitors may cause oscillation or excessive overshoot during load transients, particularly above 3A step changes.

Can this regulator operate with a 2.5V input to produce 1.8V output?

No - the minimum input voltage must exceed the desired output by at least the dropout voltage. At 5A, dropout is 1.35V typical, so 1.8V output requires ≥3.15V input. At light loads (<100mA), dropout drops to ~0.8V, still requiring ≥2.6V input for 1.8V output. Operation below dropout causes unregulated output collapse.

How does the ADJ pin current affect output voltage accuracy?

The ADJ pin draws 55–120µA, which flows through the bottom resistor (R1) of the feedback divider. This introduces an error term: V_OUT = V_REF × (1 + R2/R1) + I_ADJ × R2. For 1.25V reference and 1.8V output, using R1 = 10kΩ yields ~1.2% error; selecting R1 ≤ 2.4kΩ reduces this to <0.3%, preserving datasheet accuracy.

Is thermal shutdown reversible, and what is the hysteresis?

Yes - thermal shutdown is fully reversible with built-in hysteresis. The device disables output when junction temperature reaches +150°C and resumes regulation once junction cools to approximately +135°C. This 15°C hysteresis prevents cycling during marginal thermal conditions and allows safe recovery without manual reset or power cycle.