Driver circuits (20) for driving light circuits (21) comprising light emitting diodes are provided with converters (22) for converting input signals into output signals comprising pulses per cycle. The converters (22) comprise adapters (33) for, in response to differences between measured amplitude values of the input/output signals and nominal amplitude values of the input/output signals, adapting widths of the pulses. Then, signals having relatively precise amplitudes are no longer required. Said adapting may comprise increasing/decreasing the widths in case the measured amplitude value is smaller/larger, respectively, than the nominal amplitude value. The measured amplitude value divided by the nominal amplitude value is equal to a correction value. An adjusted duty cycle of the output signal may be made equal to a nominal duty cycle of the output signal divided by the correction value. Said adapting may be performed in a production/testing process environment.