THL3504

Overview

The THL3504 is a 24-channel constant current LED driver IC manufactured by CEL. It features individual 256-step brightness control per channel and overall 64-step dimming via embedded oscillator and PWM circuits. The device utilizes a 2-wire serial LVDS interface for high-speed, noise-resistant communication up to 10Mbps, supporting relay functions and addressable cascading. Key electrical specifications include a maximum output sink current of 40mA per channel and an output voltage withstand capability of 40V. It is housed in a 48-QFN (7x7) package.

Feature Summary

• Provides 24 independent constant current outputs with individual 256-step grayscale adjustment capabilities.
• Integrates a 2-wire serial LVDS interface enabling robust, high-speed data transmission and long-distance connectivity.
• Supports cascaded connections and multi-point addressing to simplify system wiring and reduce CPU load.
• Includes built-in oscillator and PWM controllers for precise backlight and signage illumination management.

Applications

• LED backlight systems for displays
• Commercial and architectural LED signage
• Cascaded LED matrix configurations

Procurement Notes

Verify the specific suffix (e.g., -B) against the manufacturer's official datasheet to confirm pinout compatibility and packaging variations. Ensure the design supports LVDS signaling requirements and that the 40V output rating aligns with the target LED string voltage. Confirm RoHS compliance status through the latest production documentation before finalizing procurement orders.

Selection Notes

Select this component when designing systems requiring high channel density with individual per-LED dimming control. The LVDS interface is critical for applications demanding noise immunity over longer trace lengths or complex cascaded topologies. Consider the 40mA output limit when sizing LED loads and ensure the thermal performance of the QFN package meets the application's power dissipation requirements under full load conditions.

Part Context

The THL3504 belongs to CEL's portfolio of specialized LED driver integrated circuits designed for professional display and lighting applications. It addresses the need for scalable, high-resolution LED control solutions that minimize external microcontroller processing overhead through its dedicated hardware-based PWM and grayscale generation capabilities.

Replacement Considerations

Check for direct cross-references from CEL or other manufacturers offering identical 24-channel LVDS-driven LED drivers. Verify that any substitute maintains the same 40QFN footprint, 40mA current rating, and LVDS protocol compatibility to ensure seamless integration without PCB redesign.

FAQ

How is brightness controlled on the THL3504?

Brightness is managed through an embedded oscillator and PWM controller, allowing for 256-step individual channel adjustment and 64-step overall dimming.

What type of interface does the THL3504 use for communication?

It uses a 2-wire serial LVDS interface, which supports high-speed transmission up to 10Mbps and enables cascaded connections.