Diodes Incorporated ZXLD1366EN8TC

Overview

ZXLD1366EN8TC from Diodes Incorporated is a continuous-mode inductive step-down LED driver IC qualified to AEC-Q100 Grade 1, designed for automotive and industrial LED lighting systems. It delivers up to 1A output current with ±0.8% accuracy, operates from 6V–60V input, and uses high-side current sensing via an external resistor (RS) to set nominal LED current. Its ADJ pin enables DC voltage or PWM-based brightness control with 1000:1 dimming resolution.

For engineers reviewing the ZXLD1366EN8TC datasheet, ZXLD1366EN8TC pinout, ZXLD1366EN8TC application, or ZXLD1366EN8TC equivalent, this device is selected for high-accuracy constant-current LED driving where thermal robustness (−40°C to +125°C), open-circuit protection, and single-pin on/off/dimming functionality are critical in safety-compliant lighting designs.

Technical Context

The ZXLD1366EN8TC implements a self-oscillating buck converter architecture with internal NMOS switch (RLX = 0.50 Ω typ), using VSENSE feedback referenced to VIN to regulate average LED current. Its comparator-driven control loop maintains switching by comparing ISENSE-derived voltage against a 200mV threshold (±15% hysteresis), with ADJ pin biasing the reference point.

Current regulation relies on high-side sensing across RS, where IOUTnom = 0.2V / RS. The ADJ pin serves three roles: floating for nominal operation (VADJ = 1.25V), <0.2V for shutdown (IINQoff = 65 µA typ), and 0.3–2.5V DC or PWM for proportional current scaling-enabling precise analog dimming or high-resolution digital dimming without external MOSFETs.

Key Specifications

Pinout & Package

V-DFN3030-6 package: 3.0 mm × 3.0 mm × 0.75 mm body, exposed thermal pad (EP) connected to substrate and required to be soldered to GND plane for thermal performance (θJA = 44°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ZXLD1366EN8TC, AL8862SP-13 trades single-pin simplicity for higher-frequency EMI control, while LT3477EDE#TRPBF adds diagnostics and precision at the cost of increased external components and no integrated PWM dimming path.

Availability

ZXLD1366EN8TC is available at Aetrix Electronics and suitable for automotive exterior lighting, industrial emergency lighting, refrigeration cabinet lighting, and SELV architectural signage requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ZXLD1366EN8TC 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 manufacturer specializing in discrete, analog, and mixed-signal solutions, with emphasis on reliability, efficiency, and automotive-grade qualification.

The ZXLD1366 belongs to Diodes' high-accuracy LED driver product line, engineered specifically for AEC-Q100-compliant constant-current lighting in thermally demanding environments where precision, integration, and fault resilience are mandatory.

FAQ

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

The minimum RS value is 0.2 Ω, which sets IOUTnom = 0.2V / 0.2Ω = 1A when the ADJ pin is floating at 1.25V. Using RS < 0.2Ω risks exceeding the 1.25A absolute maximum LX switch current rating and violates recommended operating conditions per DS31992 Rev. 9-2.

How does the ADJ pin function in shutdown mode?

Applying ≤0.2V to the ADJ pin disables the internal regulator and LX switch, reducing quiescent supply current to 65 µA typical. The internal reference remains active to maintain shutdown state, and LX leakage stays below 5 µA - enabling ultra-low-power standby in battery-backed lighting systems.

Can ZXLD1366EN8TC drive multiple parallel LED strings?

No - the device regulates current through a single series string only. Parallel LED strings require individual current-setting resistors and separate drivers per string to prevent current imbalance due to Vf mismatch; the ZXLD1366EN8TC lacks multi-channel or current-mirror capability.

What thermal pad connection is required for the V-DFN3030-6 package?

The exposed thermal pad (EP) must be soldered to a dedicated GND copper pour on the PCB to achieve θJA = 44°C/W. It is electrically connected to the die substrate and must not be left floating or tied to any voltage other than 0V; it should not carry GND return current to avoid noise coupling into the current sense path.