The constant-current value (ISET) of all 24 channels is set by a single external resistor, RIREF. The value of RIREF can be calculated by Equation 1.
With the IREF pin floating, the output current is close to zero. With the IREF pin shorted to GND, the LP50xx device provides internal current-limit protection, and the output-channel maximum current is limited to ILIM.
The LP50xx device supports two levels of maximum output current, IMAX.