Diodes Incorporated AZ1117T-3.3E1

Overview

AZ1117T-3.3E1 from Diodes Incorporated is a fixed-output 3.3V, 1A low-dropout linear regulator in TO220-3 package, featuring 1.15V dropout at full load, ±1% output voltage accuracy over temperature, and integrated thermal shutdown and current limiting. It delivers stable power to microcontroller cores, DDR memory rails, and USB peripheral interfaces in space-constrained industrial control modules.

For engineers reviewing the AZ1117T-3.3E1 datasheet, AZ1117T-3.3E1 pinout, AZ1117T-3.3E1 application, or AZ1117T-3.3E1 equivalent, key selection criteria include dropout voltage at 1A, thermal resistance (θ_JA = 60°C/W), output voltage tolerance across -40°C to +125°C, and compatibility with 10µF–22µF ceramic or tantalum output capacitors.

Technical Context

The AZ1117T-3.3E1 uses a trimmed bandgap reference and PNP pass transistor architecture to maintain regulation under varying line and load conditions. Its internal current limit is factory-trimmed to 1.25–1.35A, and thermal shutdown activates at +150°C junction temperature with +25°C hysteresis.

It operates across an input range of 4.75V to 15V and supports output capacitance from 10µF to 22µF (tantalum) or ≥10µF ceramic with ESR ≤ 1Ω. Ripple rejection is 60–75dB at 120Hz, and RMS output noise is 0.003% of V_OUT (10Hz–10kHz).

Key Specifications

Pinout & Package

TO220-3 package with exposed tab (pin 2) electrically connected to V_OUT, offering low thermal resistance (θ_JA = 60°C/W, θ_JC = 10°C/W) when mounted on heatsink.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MIC29302WU-3.3 and LD1117S33TR, the AZ1117T-3.3E1 offers optimal balance of 1A capability, TO220 thermal performance, and industrial temperature support - making it preferred for mid-power industrial and telecom infrastructure where reliability and heatsink flexibility matter.

Availability

AZ1117T-3.3E1 is available at Aetrix Electronics and suitable for PC motherboard power delivery, LCD monitor logic supplies, and industrial PLC I/O modules requiring stable component supply with long-term lifecycle assurance.

Supply support for AZ1117T-3.3E1 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, with design centers across Asia, Europe, and the U.S., serving industrial, computing, and communications markets.

The AZ1117 series was developed for cost-effective, robust local regulation in high-volume computing and consumer electronics, emphasizing thermal resilience, accuracy, and broad package compatibility across legacy and modern assembly processes.

FAQ

What is the minimum input voltage required for stable 3.3V output at 1A?

The AZ1117T-3.3E1 requires a minimum input voltage of 4.45V (3.3V + 1.15V dropout) to maintain regulation at 1A load. Input voltage must remain ≥4.75V per recommended operating conditions to ensure specified performance across temperature and line variation.

Can AZ1117T-3.3E1 be used with ceramic output capacitors?

Yes - the AZ1117T-3.3E1 is stable with ceramic output capacitors ≥10µF and ESR ≤ 1Ω. Unlike older LDOs, it does not require minimum ESR, eliminating the need for damping resistors or tantalum alternatives in space-constrained designs.

Is the TO220-3 package thermally enhanced, and how is the tab connected?

The TO220-3 package features an exposed metal tab (pin 2) internally connected to the OUTPUT terminal. When mounted to a heatsink, this provides direct thermal conduction path with θ_JC = 10°C/W, enabling reliable 1A operation at +70°C ambient without forced air.

Does AZ1117T-3.3E1 support reverse-voltage protection?

No - the AZ1117T-3.3E1 lacks built-in reverse-voltage protection. If input polarity reversal is possible in the system, an external series Schottky diode (e.g., 1N5819) must be added between input and the regulator's INPUT pin to prevent device damage.