LM3503SQ-44

LED Driver IC Overview

The LM3503SQ-44 is a dual-display constant current LED driver manufactured by Texas Instruments. It features an internal boost DC-DC converter capable of delivering up to 750mA switch current with a maximum output voltage of 44V. The device supports analog and PWM dimming for brightness control. It operates within a supply voltage range of 2.5V to 5.5V and functions at a switching frequency of 1MHz. The component is housed in a 16-WQFN (4x4) package and is rated for an operating temperature range of -40°C to +85°C.

LED Driver IC Feature Summary

• Dual-channel constant current drive capability for independent display segments
• Integrated high-voltage boost converter supporting up to 44V output
• Supports both analog and pulse-width modulation dimming methods

LED Driver IC Applications

• LED backlight drivers for mobile devices
• Multi-segment LCD bias generation
• High-density portable electronic displays

LED Driver IC Procurement Notes

Verify the specific suffix and RoHS compliance status, as documentation indicates potential variations between NOPB and non-NOPB versions regarding environmental standards. Confirm the obsolete or active status through official Texas Instruments channels prior to design-in, as availability may be limited. Ensure the selected package variant matches the required thermal and mechanical specifications for the target application.

LED Driver IC Selection Notes

Select this component when designing circuits requiring dual-channel LED driving with high output voltage capabilities from a low-voltage supply. The integrated boost topology simplifies bill of materials by eliminating external inductors for lower voltage needs. Consider the 1MHz switching frequency for compact passive size requirements. Verify that the 750mA channel current meets the specific LED string requirements without exceeding thermal limits in the 16-WQFN package.

LED Driver IC Part Context

The LM3503 belongs to a family of LED drivers designed for portable electronics. The SQ-44 variant specifically denotes the version optimized for higher voltage outputs up to 44V, distinguishing it from lower voltage counterparts like the LM3503SQ-16. This part serves as a power management solution for complex display systems requiring precise current regulation across multiple channels.

LED Driver IC Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Designers should consult Texas Instruments directly for current alternatives or obsolescence management strategies.