Diodes Incorporated AZ1117IH-3.3TRG1

Overview

AZ1117IH-3.3TRG1 from Diodes Incorporated is a fixed-output 3.3 V low-dropout linear regulator in SOT223 package, delivering up to 1.35 A with ±1% output voltage accuracy, 1.2 V typical dropout at 0.8 A, and integrated thermal shutdown. It powers USB devices and PC motherboard auxiliary rails where stable low-noise 3.3 V supply is critical under industrial temperature conditions.

For engineers reviewing the AZ1117IH-3.3TRG1 datasheet, AZ1117IH-3.3TRG1 pinout, AZ1117IH-3.3TRG1 application, or AZ1117IH-3.3TRG1 equivalent, key selection factors include dropout voltage at full load, PSRR at 120 Hz, RMS output noise (% of VOUT), thermal shutdown threshold, and compatibility with low-ESR ceramic capacitors.

Technical Context

The AZ1117IH-3.3TRG1 uses a trimmed bandgap reference for precise 3.3 V regulation and incorporates current-limit protection (1.35 A typ) plus thermal shutdown triggered at +160 °C junction temperature with +16 °C hysteresis. Its architecture supports operation from −40 °C to +125 °C ambient without derating when properly heatsinked.

It requires ≥10 µF low-ESR ceramic output capacitance (ESR < 20 Ω) and achieves 70 dB PSRR at 120 Hz with 22 µF output capacitor. Quiescent current remains ≤6 mA across load and temperature, enabling efficient standby operation in power-sensitive embedded systems.

Key Specifications

Pinout & Package

SOT223 package: 3-pin surface-mount device with exposed thermal pad (pin 2 is output, pin 1 is input, pin 3 is ground). Thermal resistance θ_JA = 125 °C/W (no heatsink), θ_JC = 15 °C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-3302E/MB and TLV1117-33IDCYR, AZ1117IH-3.3TRG1 delivers 69% more output current than the TLV1117 and 350% more than the MCP1700, while maintaining tighter ±1% accuracy and lower 1.2 V dropout - making it optimal for industrial-grade 3.3 V rails demanding robustness and precision.

Availability

AZ1117IH-3.3TRG1 is available at Aetrix Electronics and suitable for USB peripheral power, PC motherboard auxiliary rails, DVD player digital logic, and add-on card interface power requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for AZ1117IH-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 manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The AZ1117I series targets industrial and commercial power management applications requiring high accuracy, low noise, and extended temperature operation - designed specifically for replacing legacy 78xx regulators in space-constrained, thermally demanding systems.

FAQ

What is the minimum required output capacitance for stable operation?

The AZ1117IH-3.3TRG1 requires a minimum 10 µF ceramic output capacitor with ESR less than 20 Ω. This value ensures phase margin stability across temperature and load; using smaller or higher-ESR capacitors may cause oscillation or poor transient response. The datasheet confirms stability with X5R/X7R dielectrics meeting these criteria.

Can this LDO operate with an input voltage of 4.5 V?

Yes - with a 1.2 V typical dropout voltage at 0.8 A, the AZ1117IH-3.3TRG1 regulates stably down to 4.5 V input (3.3 V + 1.2 V). At 1 A load, worst-case dropout is 1.3 V, so 4.6 V minimum input is recommended for full-spec operation across temperature and process variation.

Is the SOT223 package lead-free and RoHS compliant?

Yes - AZ1117IH-3.3TRG1 is fully RoHS 3 compliant (2015/863/EU), halogen- and antimony-free ("Green"), with matte tin-plated leads solderable per MIL-STD-202, Method 208. Moisture sensitivity level is J-STD-020 Level 3, requiring bake before reflow if exposed beyond floor life.

How does thermal shutdown behave during sustained overload?

Thermal shutdown activates at +160 °C junction temperature and holds output off until junction cools by +16 °C hysteresis (to +144 °C). During continuous overload, the device cycles on/off - limiting average power dissipation and preventing permanent damage. PCB copper area and thermal vias directly beneath the exposed pad significantly improve cycle frequency and safe operating time.