The LT8304 has a minimum load requirement to ensure accurate output voltage is being feedback to the controller. The LT8304 samples the isolated output voltage from the primary-side flyback pulse waveform, which occurs when the primary switch turns off and the secondary winding conducts current. To sample the output voltage, the LT8304 must turn on and off for a minimum duration and at a minimum frequency. Even during light load conditions, the LT8304 delivers a minimum amount of energy to ensure accurate output voltage information. This minimum energy delivery establishes a minimum load requirement. The LT8304 generally requires less than 0.5% of its full load power as the minimum load. When designing the circuit, ensure to verify the minimum load requirement in real applications.