The FAN5345 is an asynchronous constant-current LED driver that drives LEDs in series to ensure equal brightness for all the LEDs. FAN5345S20X has an output voltage of 20 V and can drive up to 5 LEDs in series. FAN5345S30X has an output voltage of 30 V and drive up to 8 LEDs in series. Optimized for small form-factor applications, the 1.2 MHz fixed switching frequency allows the use of small inductors and capacitors.The FAN5345 uses a simple single-wire digital control interface to program the brightness levels of the LEDs in 32 linear steps by applying digital pulses.For safety, the device features integrated over-voltage, over-current, short-circuit detection, and thermal-shutdown protection. In addition, input under-voltage lockout protection is triggered if the battery voltage is too low.