Diodes Incorporated AZ1117BH-3.3TRE1

Overview

AZ1117BH-3.3TRE1 from BCD Semiconductor Manufacturing Limited is a fixed-output 3.3V, 600mA low dropout linear regulator in SOT-223 package, featuring ±1% output voltage accuracy, 1.2V typical dropout at 800mA, and integrated thermal shutdown. It delivers stable power to USB peripherals, PC motherboard subsystems, and add-on cards where low-noise, low-input-voltage operation is critical.

For engineers reviewing the AZ1117BH-3.3TRE1 datasheet, AZ1117BH-3.3TRE1 pinout, AZ1117BH-3.3TRE1 application, or AZ1117BH-3.3TRE1 equivalent, key selection criteria include dropout voltage at full load, PSRR at 120Hz, RMS output noise (0.003% of VOUT), quiescent current (max 6mA), and thermal shutdown junction temperature (160°C).

Technical Context

The AZ1117BH-3.3TRE1 uses a trimmed bandgap reference for precision regulation and incorporates internal current limiting (1.0A typ.) and thermal protection with 16°C hysteresis. Its architecture supports stable operation with only 10μF input and 22μF output ceramic capacitors.

Designed for low-voltage systems, it maintains regulation down to VIN = VOUT + 1.2V at 800mA and achieves 70dB ripple rejection at 120Hz with 3V headroom. The device operates across –20°C to +125°C junction temperature and features 0.5% temperature stability over that range.

Key Specifications

Pinout & Package

The AZ1117BH-3.3TRE1 is housed in an industry-standard SOT-223 package with exposed thermal pad (pin 2 connected to die attach paddle). This thermally enhanced outline enables up to 1.0W dissipation without heatsink at TA=25°C (θJA = 150°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1117M-3.3 and LD1117S33TR, the AZ1117BH-3.3TRE1 offers superior output accuracy (±1% vs. ±2%), lower RMS noise (0.003% vs. unspecified), and verified 70dB PSRR-making it optimal for noise-sensitive digital interfaces where voltage precision and ripple rejection are prioritized over maximum current capability.

Availability

AZ1117BH-3.3TRE1 is available at Aetrix Electronics and suitable for USB device power, PC motherboard I/O regulation, and DVD player subsystems requiring stable component supply with long-term lifecycle support.

Supply support for AZ1117BH-3.3TRE1 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

BCD Semiconductor Manufacturing Limited is a China-based analog and power IC designer specializing in high-reliability, cost-optimized linear regulators, MOSFETs, and LED drivers for consumer, computing, and industrial markets.

The AZ1117B series was developed to deliver precision, low-noise 3.3V/5.0V regulation in compact SOT-223/SOT-89 packages for space-constrained embedded systems where thermal robustness and supply rejection are essential.

FAQ

What is the minimum input voltage required for AZ1117BH-3.3TRE1 to maintain regulation at 600mA?

The minimum input voltage is calculated as VOUT + VDROP = 3.3V + 1.2V = 4.5V. At 600mA, the actual dropout is typically ≤1.2V per datasheet Figure 10 and Table 5, so 4.5V ensures regulation across temperature and process variation. Input below 4.5V risks dropout and output sag.

Can AZ1117BH-3.3TRE1 replace adjustable AZ1117B-ADJ in existing designs?

No direct replacement: the -3.3TRE1 is a fixed-output variant with internal resistor divider, while the ADJ version requires two external resistors to set VOUT. Swapping requires removing R1/R2 and verifying input headroom, as the fixed version lacks adjust pin functionality and cannot be reconfigured.

Is a minimum load current required for stability with AZ1117BH-3.3TRE1?

Yes-minimum load current is 1.7mA (typ.) to 5mA (max) per Table 5. Below this, output may oscillate or exhibit poor line/load regulation. A 1kΩ pull-down resistor (3.3mA) satisfies this requirement and is commonly used on unused LDO outputs.

How does thermal performance differ between SOT-223 and SOT-89 packages for this part?

SOT-223 has θJA = 150°C/W and θJC = 33°C/W; SOT-89 has θJA = 210°C/W and θJC = 39°C/W. With identical PCB copper area, SOT-223 dissipates ~40% more power before reaching 125°C junction limit-making it preferred for >300mA continuous loads or elevated ambient temperatures.