CAT4003BSD-GT3

Overview

The CAT4003BSD-GT3 is a programmable constant current LED driver from onsemi, featuring three matched low-dropout current sinks. It operates within a supply voltage range of 2.4 V to 5.5 V and supports output currents up to 40 mA per channel. The device utilizes the EZDim interface for digital dimming control with 32 linear levels. It eliminates the need for external sense resistors by internally setting the initial LED current to 25 mA upon power-up. The component is housed in a compact SC-70-6 package.

Feature Summary

• Provides three independent low-dropout current sinks for precise LED brightness matching
• Integrates EZDim logic input for digital control and 32-level linear dimming capability
• Features internal current setting that removes the requirement for external sense resistors
• Supports direct powering from lithium-ion batteries due to ultra-low dropout voltage

Applications

• Portable electronic devices requiring efficient LED backlighting
• Mobile phone display illumination systems
• Digital camera flash and indicator lighting circuits
• Battery-operated consumer electronics with space constraints

Procurement Notes

Verify the specific suffix BSD against the official onsemi datasheet to confirm pinout and thermal characteristics. Ensure the SC-70-6 package dimensions align with PCB layout requirements. Cross-reference the part number with authorized distributors to confirm availability status and authenticity. Check for any recent product change notices affecting electrical parameters or packaging specifications before finalizing procurement.

Selection Notes

Select this component when designing circuits requiring three independently controlled LED channels with minimal external passive components. The internal current setting simplifies design complexity compared to resistor-based solutions. Consider the 2.4 V minimum operating voltage for compatibility with single-cell lithium-ion battery systems. Evaluate the SC-70-6 footprint if board space is limited, ensuring thermal dissipation meets application demands under maximum load conditions.

Part Context

This part belongs to the CAT4003B series of programmable LED drivers from onsemi. The family includes variants with different channel counts and package options, such as the four-channel CAT4004B. These devices are designed for portable applications where efficiency and size are critical. The CAT4003B specifically targets designs needing three matched current sources with digital dimming control capabilities.

Replacement Considerations

Direct substitutes include other CAT4003B variants with compatible pinouts and electrical specifications. Verify that alternative packages maintain the same thermal performance and physical dimensions. Ensure replacement parts support the same EZDim interface and current programming methods to maintain circuit functionality without redesign.