An electronic circuit for transmitting an ASK signal, wherein the ASK signal transmits data and energy between a first side having a first interface, and a second side having a second interface corresponding to the first interface. The first interface and the second interface are embodied for transmitting data and energy, and the first interface and the second interface are embodied as galvanically separated interfaces, comprising a converting apparatus for transforming data, especially a digital data signal, into an analog wanted signal; a carrier source for producing a carrier signal having a carrier frequency; a resonator circuit for merging the carrier signal with the wanted signal to form the ASK signal with an amplitude. The resonator circuit is so embodied that it is excited by the carrier signal to execute periodic oscillations, wherein the ASK signal includes the wanted signal and the periodic oscillations, and wherein essentially the wanted signal determines the amplitude of the ASK signal. A measurement circuit for measuring the power of the ASK signal; and a data processing unit, which is so embodied that it controls the transmission of the ASK signal, wherein the controlled variable is the measured power of the ASK signal, and wherein the manipulated variable is the carrier frequency. The invention relates further to a method.