The MAX6981 serial-interfaced LED driver provides eight open-drain, constant-current-sinking LED driver outputs rated at 36V. The device operates from a 3V to 5.5V supply. The MAX6981 supply and the LEDs' supply can power up in any order. The constant-current outputs are programmed together up to 55mA using a single external resistor. The MAX6981 operates with a 25Mbps, industry-standard, 4-wire serial interface. The MAX6981 includes circuitry that automatically detects open-circuit LEDs. Fault status is loaded into the serial-interface shift register when LE goes high and is automatically shifted out on DOUT when the next data transmission is shifted in.