W5100S-POE-EVB-PICO(POE development board for RP2040)

I often use W5100S-EVB-PICO, this time I want to add POE (Power over Ethernet) function to W5100S-EVB-PICO while maintaining the original compatibility and keeping the size unchanged. The only difference is that I Change the MICRO -USB interface to TYPE-C interface.

My POE function is realized by adding a sub-board. Two rows of POE pins are added to the bottom board of the original W5100S-EVB-PICO. In this way, the POE module can also be removed when the POE function is not used.

The POE module uses two rows of 2.54mm pins, each with four pins. They are AC-IN and DC-OUT.

I made two versions of the POE module, the isolated version with a transformer and the non-isolated version without a transformer.

These two POE modules use the same chip solution. There are two main parts inside this chip, namely the PD part and the DC-DC part, as shown in the figure below:

So when we use it, we can adjust the DC-DC output to 12V, 5V, 3.3V, etc.

There are two different reference circuits in the manual, corresponding to my two different POE modules.

The following are some pictures of the POE module after testing:

At present, only the functional test has passed, and there are still many areas that need to be further improved. For example, when the load of the isolated version is relatively low, it may fail to shake hands with the POE switch. I already have a solution and will correct it in the next version（Rev 1.1）.

I have also used this POE module in "Cloud Camera" project:

This is the current progress of the test, if there is any change, I will update the progress at any time.

Done！