Electric circuit, especially for driving cold cathode tubes in integrated systems e.g. for displays and instruments in motor vehicle, has step-down device switch driven depending on tube drive signals generated from supply voltage

摘要

The circuit has a controller with a d.c. supply (4), a step-down device (5) connected to the supply to produce an intermediate circuit voltage with defined values and a converter (6) for converting the intermediate voltage into an a.c. voltage in the high voltage range for application to the cold cathode tube (2). The step-down device's switch (50) can be driven by the controller depending on tube drive signals generated from the supply voltage.