One or more embodiments provide circuitry for isolation and communication of signals between circuits operating in different voltage domains using capacitive coupling. The embodiments utilize capacitive structures having increased breakdown voltage in comparison to previous parallel plate implementations. The capacitive isolation is provided by parallel plate capacitive structures, each implemented to have parallel plates of different horizontal sizes. Due to the difference in horizontal size, edges of the parallel plates, where electric fields are the strongest, are laterally offset from the region where the parallel plates overlap. As a result, breakdown voltage between the parallel plates is increased.