The problem with ETH_RESET

chenbingjy

The problem with ETH_RESET [Copy link]

First, here are the pictures: I designed an Ethernet circuit based on the STM32F767 development board. I don’t know how to deal with the ETH_RESET pin. I can’t understand the schematic. Can an expert explain it to me? Thank you!

topwon

When the system finds that the network port chip LAN8720A is not working properly, such as being unable to connect to the Internet for a long time, this pin can be used to force the LAN8720A to reset and restart.

topwon

LAN8720A seems to be reset at a low level, so under normal circumstances, P7 output should be set low, and after the inversion of transistor Q1, ETH_RESET is always at a high level. When reset is required, P7 is set high for a short time to form a low-level reset signal on ETH_RESET.

chenbingjy

topwon posted on 2018-11-2 09:52 LAN8720A seems to be a low-level reset, so under normal circumstances, the P7 output should be set low, and after the inversion processing of the transistor Q1, ETH_RESE ...

Thank you!