Diodes Incorporated ZXLD1366DACTC

Overview

ZXLD1366DACTC from Diodes Incorporated is a continuous-mode inductive step-down LED driver IC designed for automotive and industrial lighting systems. It delivers up to 1 A output current with ±0.8% accuracy, operates from 6 V to 60 V input, features high-side current sensing via external resistor, and supports PWM or DC dimming control on the ADJ pin. Used in emergency lighting and illuminated signs where stable current regulation across wide temperature ranges is critical.

For engineers reviewing the ZXLD1366DACTC datasheet, ZXLD1366DACTC pinout, ZXLD1366DACTC application, or ZXLD1366DACTC equivalent, this page provides verified technical context, validated pin functions, confirmed thermal performance (θJA = 44°C/W), real-world dimming resolution (1000:1), and AEC-Q100 Grade 1 qualification for -40°C to +125°C ambient operation.

Technical Context

The ZXLD1366DACTC implements a self-oscillating buck converter architecture with internal comparator-based current regulation. Its high-side ISENSE pin monitors voltage drop across an external sense resistor to set nominal LED current as IOUTnom = 200 mV / RS, with typical accuracy better than ±0.8% over temperature and line.

Control is centralized on the ADJ pin: floating at 1.25 V enables nominal operation; ≤0.2 V forces shutdown (I_Qoff = 65 µA); 0.3–2.5 V enables DC brightness scaling (5:1 range); and PWM injection achieves 1000:1 dimming resolution. Switching frequency varies with VIN and LED string count, typically 260 kHz at VIN = 24 V driving three LEDs.

Key Specifications

Pinout & Package

V-DFN3030-6 package: 3.0 mm × 3.0 mm × 0.75 mm body with exposed thermal pad; RoHS-compliant, halogen-free, green molding compound.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED driver applications.

Compared with AL8862SP-13 and LM3409MY/NOPB, the ZXLD1366DACTC integrates the power switch, reference, and dimming interface into a single V-DFN3030-6 package, reducing component count by ≥4 and enabling AEC-Q100-compliant designs without external compensation or gate drivers.

Availability

ZXLD1366DACTC is available at Aetrix Electronics and suitable for emergency lighting, illuminated signs, and refrigeration lighting requiring stable component supply across automotive and industrial production cycles.

Supply support for ZXLD1366DACTC 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 ICs, specializing in power management, signal integrity, and protection solutions for automotive, industrial, and consumer markets.

The ZXLD1366 belongs to Diodes' AEC-Q100-qualified LED driver product line, engineered specifically for robust constant-current regulation in safety-critical and thermally demanding lighting applications.

FAQ

What is the minimum sense resistor value for 1 A output?

The minimum recommended sense resistor is 0.2 Ω, yielding I_OUTnom = 0.2 V / 0.2 Ω = 1 A when the ADJ pin is floating at 1.25 V. Using lower values risks exceeding the 1.25 A absolute maximum switch current and violates the device's internal current limit design margin.

How does the ADJ pin function in shutdown mode?

When the ADJ pin voltage falls to ≤0.2 V, the internal shutdown circuit disables both the LX switch and internal regulator, reducing quiescent current to 65 µA typical. The 1.25 V reference remains active to maintain bias for the shutdown comparator, ensuring fast wake-up when voltage rises above 0.25 V.

Can ZXLD1366DACTC drive parallel LED strings?

No - the ZXLD1366DACTC regulates current through a single series string only. Driving parallel strings would cause current imbalance due to V_F mismatch, risking overcurrent in one string. For multi-string applications, use one ZXLD1366 per string or select a matrix-driver IC.

What thermal design practices ensure reliability at 1 A continuous?

Solder the exposed thermal pad fully to a ≥200 mm² copper pour connected to GND; use ≥4 thermal vias (0.3 mm diameter) under the pad; keep VIN decoupling capacitor within 3 mm of VIN/GND pins; and verify junction temperature stays ≤150°C using θ_JA = 44°C/W and measured ambient.