Control circuit with data security, especially for fluorescent lamp ballast device, includes detector circuit for ascertaining working voltage failure

摘要

A control circuit (4) has a microcontroller (5) for controlling an electronic circuit (3) and which has a non-volatile store (15) and a volatile store (14), in which permanently required data are stored. A detector circuit (8) ascertains a working voltage failure and supplies a voltage failure signal to the microcontroller. A buffer circuit (6) provides brief power supply to the microcontroller (5), after failure of the operating voltage. A program is provided for driving the microcontroller, in which the program contains a program section which, with reception of the failure signal, transmits the data out of the volatile store (14) into the non-volatile store. An Independent claim is given for a method of operating the microcontroller.