LED Driver Circuit for Smooth Color Mixing During Dimming

The patent segments the LED array into multiple strings with different color temperatures (e.g., warm white and cool white LEDs). Instead of using a single analog control signal that causes inconsistent color shifts, the system divides the control into discrete segments by selectively activating different LED strings based on desired color temperature output. This segmentation allows precise control over color temperature transitions while maintaining smooth analog dimming within each string.

The patent implements a universal LED driver circuit that can control multiple LED strings with different color temperatures through a single integrated design. The driver uses a multiplexer to selectively connect different LED strings to a single control line, allowing one driver circuit to perform multiple control functions. This multi-functional approach reduces device complexity while maintaining precise control through digital signal generation and switching mechanisms.

The patent employs dynamic control by allowing the LED driver to switch between multiple discrete preset voltage levels corresponding to different color temperatures. Rather than using fixed discrete levels only, the system dynamically selects appropriate voltage levels based on real-time control signals. The multiplexer enables dynamic reconfiguration of which LED strings are active, allowing smooth transitions between discrete color temperature steps while maintaining the precision benefits of discrete control. This dynamic approach expands the effective color temperature range while preserving control precision.