Centralised control circuitry for several gas discharge lamps

摘要

The control circuit has a central unit (5) linked to peripheral control devices for the individual gas discharge lamps via a data bus. The lamps are coupled to the latter via respective coupling units (3) for transmission and reception of data. The information is supplied to the data bus as a modulated AC voltage, the coupling units feeding data to the data bus by varying the output resistance of the coupling unit transmission arm. The latter is continuously active, the reception arm being inactive when the central unit is not transmitting.