Diodes Incorporated AZ1117H-1.8TRE1

Overview

AZ1117H-1.8TRE1 from Diodes Incorporated is a fixed-output 1.8V, 1A low-dropout linear regulator in SOT223 package, featuring 1.15V dropout at full load, ±1% output voltage accuracy over temperature, and integrated thermal shutdown and current limiting. It powers core logic rails in space-constrained embedded systems requiring stable low-voltage supply under variable load.

For engineers reviewing the AZ1117H-1.8TRE1 datasheet, AZ1117H-1.8TRE1 pinout, AZ1117H-1.8TRE1 application, or AZ1117H-1.8TRE1 equivalent, key selection criteria include dropout voltage at 1A, thermal resistance (θ_JA = 120°C/W), output accuracy tolerance, minimum input voltage margin, and SOT223 thermal pad layout compatibility.

Technical Context

The AZ1117H-1.8TRE1 uses a trimmed bandgap reference and PNP pass transistor architecture to achieve 1.15V dropout at 1A while maintaining ±1% output regulation across –40°C to +125°C junction temperature. Its internal current limit is factory-trimmed to 1.25–1.35A and thermal shutdown activates at +150°C with +25°C hysteresis.

It operates with input voltages up to 15V and requires ≥3.2V input for 1.8V output under full load. The device delivers 75dB ripple rejection at 120Hz with 22µF tantalum output capacitance and exhibits 0.003% RMS output noise (10Hz–10kHz).

Key Specifications

Pinout & Package

SOT223 package with exposed thermal pad (pin 2 connected to V_OUT for thermal conduction); standard 3-pin configuration optimized for PCB heat spreading in high-current LDO applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-1802E/TT and TLV1117-18CDCYR, the AZ1117H-1.8TRE1 uniquely balances 1A capability, 1.15V dropout, ±1% accuracy, and SOT223 thermal performance-making it optimal for space-constrained 1.8V core rails where both current and precision matter.

Availability

AZ1117H-1.8TRE1 is available at Aetrix Electronics and suitable for PC motherboard design, LCD monitor production, graphic card manufacturing, and telecom equipment development requiring stable component supply and long-term sourcing continuity.

Supply support for AZ1117H-1.8TRE1 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 devices for industrial, computing, and consumer markets.

The AZ1117 series targets cost-sensitive, high-volume power management applications requiring reliable fixed-output LDO regulation in compact packages-especially for legacy and mainstream embedded systems where SOT223 thermal performance and RoHS compliance are essential.

FAQ

What is the minimum input voltage required for stable 1.8V output at 1A?

The AZ1117H-1.8TRE1 requires a minimum input voltage of 2.95V (1.8V + 1.15V dropout) to maintain regulation at 1A load. For robust operation across temperature and line variation, Diodes recommends ≥3.2V input per the datasheet's recommended operating conditions.

Does this part require an external output capacitor, and what type is specified?

Yes, a minimum 10µF ceramic or 22µF tantalum output capacitor is required for stability and transient response. The datasheet specifies 22µF tantalum for optimal ripple rejection (75dB at 120Hz); ceramic capacitors must meet ESR requirements (0.1–1Ω) to avoid oscillation.

Is the SOT223 thermal pad internally connected, and how should it be handled on the PCB?

Yes, pin 2 (OUTPUT) is electrically and thermally connected to the exposed thermal pad. The pad must be soldered to a large copper pour with multiple thermal vias to an internal ground plane to achieve the rated θ_JA = 120°C/W and prevent thermal shutdown under 1A load.

How does the AZ1117H-1.8TRE1 compare to newer alternatives like the AZ1117C series?

The AZ1117H-1.8TRE1 is marked "NOT RECOMMENDED FOR NEW DESIGN" per the datasheet, superseded by the AZ1117C series which offers improved PSRR (80dB), lower dropout (1.0V @ 1A), and enhanced thermal performance. However, AZ1117H remains fully qualified for existing designs and offers identical pinout and electrical compatibility for drop-in replacement.