Very cool, i love switch-mode converter experiments and have done some myself. I have to try this!
@Dad-ij2qy
8 ай бұрын
I don't know what you mean by the "step-down nature of the converter" at 5:58 because moving the de-energizing coil to the secondary side of the coil made the transformer a "step-up transformer", did it not? This is the way it appears to me, as omitting the de-energizing coil would make the transformer neither step-up nor step-down, but rather an isolation transformer, would it not?
@5VLogic
8 ай бұрын
So, the forward converter is a step-down (assuming a 1:1 transformer ratio) because it behaves like a buck converter (with the classic input-side demagnetizing). We can intuitively verify this by observing the voltage on the L1, D3, D5 node to be a square wave with amplitude = Uin and duty cycle < 1. Once we move the demagnetizing winding to the output, it becomes a forward and flyback combined. This makes it potentially a step-up.
@adaminsanoff
8 ай бұрын
Subscribed!
@erdum
8 ай бұрын
Subscribed.
@przoch5835
8 ай бұрын
very nice, thank you for posting. I guess you are using NE555, but can you pls share the frequency and duty cycle? thank you
@5VLogic
8 ай бұрын
The frequency is about 60kHz while I vary the duty cycle as visible on the oscilloscope bottom trace (~30% ~70%)
@JurekPrzezdziecki
10 күн бұрын
Very coo. What's the ratio of the transformer?
@5VLogic
10 күн бұрын
Thanks! It's a slight step-up, like 13:9
@JurekPrzezdziecki
10 күн бұрын
@@5VLogic thanks. So 1:1 could work as well?
@5VLogic
9 күн бұрын
Sure, just remember that the forward converter usually takes a maximum duty cycle of 50%, so you'll get less that 0.5 times the input voltage at the output.
Пікірлер: 11