Diodes Incorporated ZLDO1117G15TA

Overview

ZLDO1117G15TA from Diodes Incorporated is a fixed-output 1.5V, 1A low dropout linear regulator in SOT223 package, featuring 1.2V max dropout at full load, ±2% output voltage tolerance over industrial temperature range (−40°C to +125°C), and compatibility with MLCC output capacitors down to 4.7µF. It delivers stable power for 3.3V/1.8V logic rails, high-speed bus termination, and automotive-grade I/O supplies.

For engineers reviewing the ZLDO1117G15TA datasheet, ZLDO1117G15TA pinout, ZLDO1117G15TA application, or ZLDO1117G15TA equivalent, key selection criteria include dropout voltage under 1.2V at 1A, thermal shutdown protection, AEC-Q100 Grade 2 qualification, and stability with low-ESR ceramic capacitors - critical for compact, thermally constrained embedded power designs.

Technical Context

The ZLDO1117G15TA employs a precision bandgap reference and internal error amplifier to maintain 1.5V output with ≤6 mV load regulation (0–1A) and ≤0.2% line regulation (2.9–12V input). Its quasi-LDO architecture achieves 1.11V typical dropout at 1A while sustaining operation across −40°C to +125°C junction temperature.

Thermal protection activates at ~150°C junction temperature, disabling output until die cools; quiescent current remains ≤10mA across 2.7–18V input. The device supports fast transient response via optimized internal compensation, eliminating need for external frequency compensation components when used with 4.7µF X7R MLCCs (ESR ≤ 0.5Ω).

Key Specifications

Pinout & Package

SOT223-3L package with exposed thermal pad (Tab = VOUT); footprint optimized for 2 oz copper thermal spreading per Diodes AP02001 guidelines. Thermal resistance θ_JA = 107°C/W (standard test board), θ_JC = 16°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-1502E/MB and TLV70115DBVR, ZLDO1117G15TA uniquely combines 1A output, AEC-Q100 Grade 2, and MLCC compatibility in SOT223 - making it the only choice for thermally demanding, high-reliability 1.5V power delivery where both current and ruggedness are non-negotiable.

Availability

ZLDO1117G15TA is available at Aetrix Electronics and suitable for automotive camera modules, industrial PLC I/O subsystems, medical sensor nodes, and edge AI accelerator bias rails requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant sourcing.

Supply support for ZLDO1117G15TA 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 ICs, with emphasis on high-reliability power management and signal integrity solutions for automotive, industrial, and computing markets.

ZLDO1117G15TA belongs to the ZLDO1117 family of quasi-LDO regulators designed specifically for high-stability, low-noise, and thermally robust power delivery in automotive and industrial environments - extending beyond legacy 1117 performance with tighter tolerances and broader temperature capability.

FAQ

Is ZLDO1117G15TA pin-compatible with standard LM1117-1.5 variants?

Yes - ZLDO1117G15TA uses identical SOT223-3L pinout (Adj/GND–VOUT–VIN) and shares mechanical footprint with LM1117-1.5. However, it improves upon LM1117 with lower dropout (1.2V vs. 1.3V), tighter tolerance (±2% vs. ±3%), AEC-Q100 qualification, and guaranteed MLCC stability - enabling direct replacement in upgraded designs.

What is the minimum input voltage required for regulation at full 1A load?

The minimum input voltage is 2.7V, as specified in Recommended Operating Conditions. At 1A load, VIN must exceed VOUT by ≥1.3V to avoid dropout - so 1.5V + 1.3V = 2.8V is the practical minimum. Below this, output voltage drops linearly with input; regulation resumes once VIN rises above threshold.

Can ZLDO1117G15TA be used with 2.2µF MLCC output capacitors?

No - the datasheet mandates ≥4.7µF MLCC (X7R, ESR ≤ 0.5Ω) for guaranteed stability. Using 2.2µF risks oscillation or poor transient response due to insufficient phase margin. Larger values (10–22µF) further improve load step recovery and noise immunity without penalty.

Does ZLDO1117G15TA require an input capacitor?

An input capacitor is recommended but not strictly required for stability. A 1µF ceramic capacitor placed close to VIN improves high-frequency noise rejection and prevents input rail sag during load transients - especially when the regulator is physically distant from the main bulk capacitor in the power tree.