The demo board is designed as an isolated 12 V and 3.3 V AC/DC SMPS for supplying up to 5 W to a load. The switch-mode converter operates in flyback mode at a maximum frequency of around 51 kHz. Overcurrent and short-circuit protection are built in. The power consumption is between 10 mW and 20 mW under no-load conditions. EMI filtering and surge protection using TVS diodes is implemented in this circuit.