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+
+
+# w5500
+(datasheet)[https://docs.wiznet.io/pdf-viewer?file=%2Fassets%2Ffiles%2FW5500_ds_v110e-226ffec190c588b69f88d629789585e1.pdf]
+(applaction sch)[https://docs.wiznet.io/pdf-viewer?file=%2Fassets%2Ffiles%2Fw5500_sch_v110_use_mag_-dfff8bbb103d13be4f25cd2b2f8b950d.pdf]
+
+# poe app note
+https://media.monolithicpower.com/mps_cms_document/2/0/2023-en-wechat-poe-power-supply-process-across-ieee-802.3afatbt-protocol_r1.0.pdf
+https://www.ti.com/lit/an/slvaf59/slvaf59.pdf?ts=1786323456539
+
+# poe controller
+https://www.analog.com/media/en/technical-documentation/data-sheets/LT4295.pdf
+
+
+