Patent ID: 8358086

Claim:
An electronic ballast for a lamp, comprising: at least one dimming value control input and a control unit configured to set the dimming value of the lamp, wherein arranged downstream of the dimming value control input are: a signal output state detecting unit configured to acquire at least one of a signal output state in which the signal level of a signal fed to the dimming value control input overshoots a predetermined limit value, and signal output state in which it undershoots a predetermined limit value, and a measuring unit configured to measure the duration of a signal output state, the control unit configured to set a dimming value of the lamp being configured to set the dimming value on the basis of the measured duration of the signal output state; further comprising: at least one lamp fault detection input, and a lamp fault detecting unit configured to detect a lamp fault, wherein the lamp fault detection input is configured to serve the purpose of transmitting electric current, and wherein a connection control unit is coupled to the lamp fault detecting unit configured to detect the lamp fault is provided for setting a transmission condition as a function of whether a lamp fault has been detected or not, wherein the dimming value control input and lamp fault detection input are the same input, the signal output state detecting unit configured to acquire a signal output state and the connection control unit configured to set a transmission condition being coupled to one another, and the connection control unit is configured to prevent the transmission of current independently of the occurrence of a lamp fault as long as the signal output state is acquired.