I want to make a flyback converter, it will have to output 3.3V DC. Where the input is initially an power line 230V AC signal.
I have found this circuit which is essentially a flyback converter, controlled by a small controller which seems reasonable, this circuit first takes as an input a DC signal therefore, the incoming AC signal would be rectified to match that of a steady DC signal. Then passed on to the aforementioned circuit which is attached below.
I understand some aspects of the working of the circuit, however I would like to grasp it fully:
When the current passes through the transistor,a positive voltage is on the dot on N1 indicating the polarity of the coil on the left, an opposite polarity occurs across the second coil in the right, however this would lead to a current which can't pass through the diode since it would be reverse biased.
Therefore, ultimately current stops passing in the right section of the circuit.
and somehow the coil on the left stores energy??? How is that when it's a DC input wouldn't it act as a short circuit???
Then when the switch is open (Current no longer passes through the transistor), the energy in the left coil is somehow transferred to the coil on the right ( I guess by the back induced emf in the left coil, which will produce a current in the right coil???), and this current produced can pass through the diode thus charging the capacitor and supplying an output voltage...
When the switch is closed again (current passes through the transistor) the charged energy stored in the capacitor simply keeps driving the output.. Is this correct? and the cycles continue
1) One thing I don't understand is; what is the function of the capacitor Cin? I need to understand its function to determine its value...
2) I know that Cout is used to store the energy from the transformer, to later be transferred to the output, however quantitavely speaking how large a capacitor would I need?
Thank you all I know it's a big read. I appreciate the help!