Do i have to use a transformer if i want to make an AC to DC power supply? Can i just solely use a full bridge rectifier without a transformer present and still safely produce DC voltages?
Hi
roger has answered the question but left out a major fact the isolation is really what its all about the mains supply has infinite low impedance so a very high current is present.
the transformer increases the impedance along with the separation, otherwise exceeding large currents would flow.
Switch mode power supplies do not use a transformer as such but to reduce the mains borne interference the weight of the power supply will be significant if it is to succeed in reducing the interference in the system. so to be blunt it will be as heavy physically as it will contain a lot of metal for one reason or another.
the source impedance is also increased due to the circuitry.