cciarleg
Junior Member level 3
Hi,
I'm trying to design an isolated flybuck similar to the example design shown in AN-2292 by TI. My simulation is not turning out with the secondary voltage correctly though.
My design criteria:
Need isolated 40W (currently set to 11.5V, 3.5A). Ideally I need a controllable signal also, but starting with the basics...
My LTSpice circuit looks like this:
I am subbing in a similar schottkey for the one listed. I want to use a Coilcraft coupled inductor with low DCR. Set to operate at 900kHz currently.
A few questions:
I am not getting 11.5V or my 3.5A on the secondary output and am not sure why. Not sure if it has to do with the current ratio or not. Any suggestions would be appreciated there.
I (in theory) am going to lose something like 1.4W over the diode. Is there any way around this or am I just stuck with that?
Thanks in advance.
I'm trying to design an isolated flybuck similar to the example design shown in AN-2292 by TI. My simulation is not turning out with the secondary voltage correctly though.
My design criteria:
Need isolated 40W (currently set to 11.5V, 3.5A). Ideally I need a controllable signal also, but starting with the basics...
My LTSpice circuit looks like this:
I am subbing in a similar schottkey for the one listed. I want to use a Coilcraft coupled inductor with low DCR. Set to operate at 900kHz currently.
A few questions:
I am not getting 11.5V or my 3.5A on the secondary output and am not sure why. Not sure if it has to do with the current ratio or not. Any suggestions would be appreciated there.
I (in theory) am going to lose something like 1.4W over the diode. Is there any way around this or am I just stuck with that?
Thanks in advance.