Power supplies of MFPs are characterized primarily by two features: one, they are switching power supplies, and two, they have protection from surges in line voltage. Also, machines with laser printers require a high-voltage supply as well as a lower voltage supply. The latter supplies power to the high-voltage supply. In MFPs with inkjet printers, it supplies 24 V as well as voltages below that level. In addition, it may supply a higher voltage to the printer. In machines with laser printers at least six higher voltages are provided to various components of the laser print engine.
The block diagrams of switching power supplies in two Brother MFPs follow (they are reproduced with permission).