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I've been reading the data sheet for a power over Ethernet module, the si3402-B.

There is an application schematic which shows how the system is typically designed. However, it says it's a simplified schematic and for full info see the reference design of the evaluation board. It shows the circuit design of the evaluation board which is very confusing, because I don't know what to implement from it; the reference design or the simplified version?

I'm sorry for this question, as I am not so good in hardware design.

Hint: The reference design is not providing any features except input and output, just like the simplified version, but as a more complex view.

Thanks in advance!

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The simplified schematics show only where the power is coming from and going to (so you get an idea of the basic operation), but omit a few parts that are required for correct operation (e.g. capacitors that reduce voltage swing in certain corner cases).

You will need to implement the reference design unless you know what you can omit or alter in your application. Take a lot of care keeping loops small in the switching converter, as the reference design says.

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  • \$\begingroup\$ Last question. The output is applied in inductor connector. Can i remove that inductor because the design will be implemented in the same pcb for the main device \$\endgroup\$ – user8886528 Nov 11 '17 at 11:44
  • \$\begingroup\$ @user8886528, there are two reference designs, an isolating one in case the device has another ground reference, and a non-isolating one in case it doesn't. "Same PCB" is not the determining factor here, but whether the device has any connections to devices that may have a different idea of ground (Ethernet can be run to a different building). \$\endgroup\$ – Simon Richter Nov 13 '17 at 8:44

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