Diodes Incorporated AZ1117IH-1.8TRG1

Overview

AZ1117IH-1.8TRG1 from Diodes Incorporated is a fixed-output 1.8 V low-dropout linear regulator in SOT223 package, delivering up to 1.35 A output current with ±1% output voltage accuracy, 1.2 V typical dropout at 0.8 A, and integrated thermal shutdown. It serves as a primary post-regulator for FPGA core supplies, USB peripheral power rails, and industrial microcontroller I/O domains requiring stable low-voltage bias under transient load.

For engineers reviewing the AZ1117IH-1.8TRG1 datasheet, AZ1117IH-1.8TRG1 pinout, AZ1117IH-1.8TRG1 application, or AZ1117IH-1.8TRG1 equivalent, key selection criteria include dropout voltage at 800 mA, PSRR at 120 Hz, RMS output noise (% of VOUT), thermal shutdown junction temperature, and compatibility with low-ESR ceramic capacitors (≤20 Ω).

Technical Context

The AZ1117IH-1.8TRG1 employs a trimmed bandgap reference and internal current-limit circuitry to maintain ±1% output accuracy across –40°C to +125°C junction temperature. Its thermal protection activates at +160°C with +16°C hysteresis, preventing latch-up during sustained overload or high ambient conditions.

Designed for low-noise, high-transient-response applications, it achieves 0.003% RMS output noise (10 Hz–10 kHz) and 70 dB PSRR at 120 Hz with 22 µF output capacitance. The device operates with input voltages up to 15 V and requires only a 10 µF minimum ceramic output capacitor with ESR < 20 Ω.

Key Specifications

Pinout & Package

SOT223 package: 3-pin surface-mount, thermally enhanced plastic outline with exposed thermal pad on leadframe (pin 2 is tab-connected to GND). Pin count and terminal assignment validated per Diodes DS38213 Rev. 2–2 Figure 1 (Top View).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout linear regulator applications.

Compared with MCP1703T-1802E/MB and TLV70118DBVR, the AZ1117IH-1.8TRG1 delivers 5.4× higher output current and 2× lower dropout than the MCP1703 while maintaining industrial temperature range and thermal robustness-making it the only viable option for 1.8 V/1 A+ applications in PC motherboards and industrial add-in cards.

Availability

AZ1117IH-1.8TRG1 is available at Aetrix Electronics and suitable for USB peripheral power, FPGA I/O bias, and industrial microcontroller I/O domains requiring stable component supply, full RoHS compliance, and guaranteed -40°C to +125°C operation.

Supply support for AZ1117IH-1.8TRG1 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 centers across Asia and manufacturing in IATF 16949-certified facilities.

The AZ1117I series targets industrial and computing applications demanding high accuracy, low noise, and rugged thermal performance in cost-sensitive, high-volume power management systems.

FAQ

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

The AZ1117IH-1.8TRG1 requires VIN ≥ VOUT + VDROP. At 1 A, maximum dropout is 1.4 V (TO252-2) or 1.3 V (SOT223); thus, minimum VIN is 3.2 V for SOT223. Operation below this causes output collapse. Input must also stay within absolute max rating of 18 V.

Can this LDO be used with a 10 µF X5R ceramic capacitor only on the output?

Yes-Diodes specifies compatibility with low-ESR ceramic capacitors ≥10 µF and ESR ≤20 Ω. A single 10 µF X5R (e.g., 0805, 16 V) meets both requirements and is sufficient for stable regulation per DS38213 Section 8.2.

Does the AZ1117IH-1.8TRG1 require an input capacitor?

While not strictly mandatory, Diodes recommends ≥10 µF aluminum or ceramic input capacitor placed close to the INPUT pin to suppress source impedance and prevent oscillation during fast load transients-especially when powered from long traces or switching regulators.

How does thermal shutdown behave during continuous overload?

When junction temperature reaches +160°C, the device shuts down output and holds off until temperature drops by +16°C hysteresis (to +144°C), then resumes regulation. This prevents thermal runaway and allows safe recovery without manual reset or power cycle.