Hi guys,
I am recently reading in Maniktalas "Switching Power Supplies A-Z". And the author does a great job describing the whole world of buck-boost and boost-buck topologies.
Even though there are some obvious differences in the basic circuits of a SEPIC and a 4 switch buck-boost DC/DC converter both do basically the same task.
Well I already know that they differ in terms of switching losses (1 Mosfet for SEPIC versus 4 Mosfets for the 4 switch buck-boost) and that the 4 switch buck-boost is likely
more difficult to control around that area where VIN equals VOUT. And I am aware that the 4 switch buck-boost can be controlled in many different ways...such as to only
clock the buck side when VIN>VOUT and vise versa. Probably the 4 switch buck-boost can also (depending on the control algorithm or control IC) be made bidirectional in terms
of power flow. Both have the same transfer function (VOUT/VIN = D/(1-D)). And so on and so forth.
But as already mentioned SEPIC or 4 switch buck-boost...both do basically the same task.
So which one to choose for which application? Are there any differences I have not covered? Advantages/Disadvantages?
