Will the switching power supply fake load how to calculate?
As for the choice of parameters, one is enough resistance power, the second is the resistance, which can make the output stability of the resistance in the small point on the line, too small will increase the no-load loss, affecting efficiency, too much to play a role.
so, at this time in the secondary parallel resistance, you can cut off part Voltage overshoot, reduce the feedback current, so that D can open.
Switching power supply fake load, the main purpose is to overcome the no-load or light load output instability. And the output is unstable, the primary D is too small, the energy is not open is the secondary overshoot voltage or feedback current is too large, forced IC to reduce D;
