As previously mentioned there are some changes for higher voltage systems and or DC systems. For higher voltage AC systems, the main concern is to pick the HV interface that will prevent most of the VAC signal from coupling into the protection circuit. The other components mainly change based on modulation frequency which is AC Mains voltage independent. The transformer used for this design is rated to 400V on the primary as its working voltage – if your application is higher than 400 V a different transformer might need to be used.

For DC applications the transformer is unnecessary and can be removed as the high voltage capacitor will block the DC voltage and extra filter is not required.