Diodes Incorporated AZ1117CH2-3.3TRG1

Overview

AZ1117CH2-3.3TRG1 from Diodes Incorporated is a fixed-output 3.3V low-dropout linear regulator in SOT223 package, delivering up to 1.35A output current with ±1% output voltage accuracy, 1.3V typical dropout at 0.8A, and 70dB PSRR at 120Hz. It integrates thermal shutdown and current limit protection, and is optimized for USB devices and PC motherboard power rails where transient response and input voltage margin are critical.

For engineers reviewing the AZ1117CH2-3.3TRG1 datasheet, AZ1117CH2-3.3TRG1 pinout, AZ1117CH2-3.3TRG1 application, or AZ1117CH2-3.3TRG1 equivalent, key selection criteria include dropout voltage at full load, output accuracy over temperature, compatibility with low-ESR ceramic capacitors (≤20Ω), minimum 10µF output capacitance requirement, and thermal resistance (θ_JA = 125°C/W, θ_JC = 15°C/W) for board-level thermal design.

Technical Context

The AZ1117CH2-3.3TRG1 uses a trimmed bandgap reference and internal error amplifier to maintain stable 3.3V output across load (1.7–1350mA) and line (4.3–15V input) variations. Its architecture includes foldback current limiting and thermal shutdown triggered at +160°C junction temperature with +16°C hysteresis.

It operates over –20°C to +125°C junction temperature, supports low-ESR ceramic output capacitors (≥10µF, ESR < 20Ω), and achieves 0.003% RMS output noise (10Hz–10kHz) - critical for noise-sensitive digital logic and analog subsystems powered from the same rail.

Key Specifications

Pinout & Package

Package: SOT223 (3-pin, standard footprint per JEDEC TO-261AA). Thermal pad on underside requires PCB copper pour for effective heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-3302E/TT and TLV73333PDBVR, the AZ1117CH2-3.3TRG1 provides 4.5× higher output current and integrated thermal hysteresis - making it the only viable option for 3.3V USB host port regulation where sustained 1A+ loads and robust thermal protection are mandatory.

Availability

AZ1117CH2-3.3TRG1 is available at Aetrix Electronics and suitable for USB devices, PC motherboards, and DVD player power subsystems requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for AZ1117CH2-3.3TRG1 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 manufacturer specializing in discrete, analog, and mixed-signal ICs, with emphasis on power management, signal integrity, and protection solutions.

The AZ1117C series is part of Diodes' precision linear regulator product line, designed specifically for low-noise, low-dropout power delivery in cost-sensitive consumer and computing applications where reliability and thermal robustness are essential.

FAQ

What is the minimum required output capacitance for stable operation?

The AZ1117CH2-3.3TRG1 requires a minimum 10µF ceramic output capacitor with ESR less than 20Ω. This value ensures phase margin >45° across temperature and load conditions. Using lower capacitance or higher-ESR types (e.g., tantalum) may cause oscillation or poor transient response, especially during USB hot-plug events.

Can this regulator operate with an input voltage below 4.3V?

No - the absolute minimum input voltage is defined by the dropout specification: V_IN(MIN) = V_OUT + V_DROP = 3.3V + 1.3V = 4.6V under full 0.8A load. At lighter loads, dropout decreases (e.g., ~0.9V at 100mA), permitting ~4.2V input, but operation below 4.3V is outside guaranteed specifications and risks output regulation loss.

Is the SOT223 package thermally enhanced compared to SOT89?

Yes - the SOT223 package has θ_JA = 125°C/W (no heatsink) and θ_JC = 15°C/W, versus SOT89's θ_JA = 170°C/W and θ_JC = 30°C/W. This means SOT223 delivers ~30% better thermal performance, enabling higher continuous current (up to 1.35A) without external heatsinking when mounted on ≥1in² copper area.

Does the device require an input capacitor?

While not strictly mandatory for stability, a ≥1µF ceramic input capacitor placed within 5mm of the INPUT pin is strongly recommended. It reduces high-frequency noise coupling from upstream supplies and limits inrush current during power-up, preventing input voltage sag that could trigger undervoltage lockout in upstream controllers.