IC-BASED LOW COST RELIABLE ELECTRONIC BALLAST ITH MULTIPLE STRIKING ATTEMPTS AND END OF LAMP LIFE PROTECTION.

摘要

The present invention relates generally to a simple, low cost ballast f or fluorescent lamps that incorporates an integrated circuit and a number of ballast protection functions to cost effectively enhance its reliability. End of lam p life circuitry is provided to shut down the ballast when rectification currents d ue to lamp aging exceed a predetermined level. This circuitry is also functions to stop the ballast operation when the lamp's voltage exceeds a predetermined cutoff lev el for a set period of time. Re-lamping circuitry is provided that restarts the balla st when new lamps are installed without shutting off the ballast. Multiple striking attempt circuitry is provided that initiates a predetermined number of striking attempts such that cold or old lamps are quickly ignited without the introduction of excessive flickering.