Power problem

Question

Hi! I use Teensy 3.2 with Wiz820io. Connection: MOSI to pin11 SCLK to pin13 SS to pin10 PWDN to GND RESET to pin9 MISO to pin12 INT without connection For power using 5v. I don’t get light on the magjack after connection the Ethernet. It damaged power? How can I check it out?

explozed · Answer

How to verify w5500 and its peripheral circuit Set RSTn into high level, and you must see LEDs turn on after inserting live cable into the jack. As I understand, this will help. How to set RSTn into high level?

Eugeny · Answer

explozed: For power using 5v. Did you supply 5V to the module? I did not have experience with it, but W5200 used in this module should be powered by 3.3V. It is declared that chip’s inputs are 5V tolerant though, but I do not recommend feeding it with 5V input signals as it creates excessive consumption current. explozed: How to set RSTn into high level? If you are looking for quick way doing it, then just connect RSTn to 3.3V supply rail directly or through 1k resistor if possible. However you must keep in mind that before reset goes high, it is highly recommended to have it low for specific amount of time stated in the datasheet. If you are looking for proper solution for the reset input, then there’re a number of circuits and manuals explaining how to generate proper digital reset signal, ranging from simple having button, resistor and cap like this one up to several specific chips designed for proper timing and signal cleanness like this one.