31FL323x LED Lighting Development Boards ISSI 31FL323x LED Lighting Development Boards are development tools that evaluate ISSI multi-channel LED drivers. LED drivers are electrical circuits used to power light-emitting diodes. The fully assembled and tested board is powered by the Arm® Cortex®-M3 or 80C51 (IS31FL3235A-QFLS2-EB) with a 5V operating supply voltage. The evaluation boards have multiple display modes.