iC-WJ SO8

Description

The iC-WJ and iC-WJZ devices are driver ICs for laser diodes in continuous and pulsed operation up to 300 kHz. The laser diode is activated via switching input IN. A control to the mean value of the optical laser power and integrated protective functions ensure nondestructive operation of the sensitive semiconductor laser. The IC contains protective diodes to prevent destruction due to ESD, a protective circuit to guard against over temperature and under voltage and a soft-start for the laser diode driver to protect the laser diode when switching on the supply voltage. An external resistor at ISET is utilised to adapt the power control to the laser diode being used. The capacitor at CI determines the recovery time constants and the start-up time. A watchdog circuit monitors the switching input IN. If IN remains low longer than preset by the capacitor at CWD, the capacitor of the power control is discharged at pin CI. This ensures that the current through the laser diode during the next high pulse at input IN is not impermissibly high.

Features