Diodes Incorporated AZ1117T-ADJE1

Overview

AZ1117T-ADJE1 from Diodes Incorporated is an adjustable low-dropout linear regulator delivering 1A output current with 1.15V dropout at full load, ±1% reference voltage accuracy (1.25V), and integrated thermal shutdown and current limiting. It operates across –40°C to +125°C and is used in PC motherboard VRMs, LCD monitor power rails, and telecom equipment DC-DC post-regulation stages.

For engineers reviewing the AZ1117T-ADJE1 datasheet, AZ1117T-ADJE1 pinout, AZ1117T-ADJE1 application, or AZ1117T-ADJE1 equivalent, key selection criteria include dropout voltage at 1A, adjustable output range (1.25V–12V), thermal shutdown threshold (+150°C), package-specific θJA (60°C/W for TO220-3), and minimum load current requirement (1.7–5mA for ADJ version).

Technical Context

The AZ1117T-ADJE1 implements a bandgap-referenced error amplifier driving a PNP pass transistor, enabling stable regulation with only two external resistors for output adjustment. Its trimmed reference ensures 1.225V–1.270V VREF over temperature and load, and internal current limit is factory-set to 1.25–1.35A.

Thermal protection activates at +150°C junction temperature with +25°C hysteresis, and the device sustains operation up to 15V input while maintaining ≤0.4% load regulation (10mA–1A) and ≤0.2% line regulation under specified VIN–VOUT differentials.

Key Specifications

Pinout & Package

TO220-3 package with exposed tab (pin 2) thermally connected to VOUT; standard through-hole mounting; no heatsink required for ≤1W dissipation at TA=25°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MIC29302WU and LD1086DT, the AZ1117T-ADJE1 offers tighter reference accuracy (±1% vs ±2%), lower quiescent current (5–10mA vs 25mA), and proven thermal robustness in TO220-3 - making it optimal for space-constrained, multi-voltage industrial designs requiring long-term stability.

Availability

AZ1117T-ADJE1 is available at Aetrix Electronics and suitable for PC motherboard power delivery, LCD monitor bias rails, and telecom line card regulation requiring stable component supply across extended temperature and long-lifecycle programs.

Supply support for AZ1117T-ADJE1 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, specializing in high-reliability power management, signal integrity, and protection solutions for industrial and computing markets.

The AZ1117 series belongs to Diodes' precision LDO portfolio, designed specifically for cost-effective, thermally robust post-regulation in computing peripherals, displays, and communications infrastructure where reliability across –40°C to +125°C is mandatory.

FAQ

What is the minimum load current required for stable operation of AZ1117T-ADJE1?

The AZ1117T-ADJE1 requires a minimum load current of 1.7mA to 5mA depending on junction temperature, as specified in the Electrical Characteristics table for the ADJ version. This ensures proper biasing of the internal error amplifier and prevents output voltage overshoot or instability, especially during light-load or no-load conditions. External loading via a bleed resistor may be necessary in systems with intermittent or zero-load states.

Can AZ1117T-ADJE1 be used with ceramic output capacitors?

Yes - the AZ1117T-ADJE1 is stable with ceramic output capacitors ≥10µF, provided they meet the recommended ESR range (0.1Ω–10Ω). Unlike older LDOs, its internal compensation does not require high-ESR tantalum or aluminum electrolytic capacitors. However, a 22µF ceramic capacitor with X7R dielectric and 10V rating is preferred for optimal transient response and ripple suppression in industrial applications.

How does the adjust pin current affect output voltage accuracy?

The adjust pin draws 60–120µA (IADJ), which flows through the lower resistor (R2) in the feedback divider, introducing an offset error in the output equation: VOUT = VREF × (1 + R2/R1) + IADJ × R2. For a target 5V output using R1 = 150Ω, selecting R2 = 4.8kΩ yields ~4.95V nominal; trimming R2 downward by ~1% compensates for IADJ-induced error and achieves ±1% final accuracy.

Is AZ1117T-ADJE1 pin-compatible with older AZ1117 variants in TO220-3?

Yes - all AZ1117 variants in TO220-3 (including -1.2E1, -3.3E1, and -ADJE1) share identical pinout (INPUT–OUTPUT–ADJ/GND), mechanical footprint, and thermal pad connection. The only functional difference is the internal voltage-setting network: the ADJ version replaces the fixed-resistor divider with open ADJ and GND pins, enabling external configuration without layout change.