seridj_mse
Member level 2
hi,
I have probelm with odd harmonics on a my clock trace 50mhz for my ESP32 and LAN8720A, for CISPR 16 radiated emission limits.
-I tried with ferrite 1k@100Mhz, i had probelm with stability of ethernet i cant open web page.
-with another ferrite MPZ1608B471ATA00 470R@150Mhz . its looks good but in my design i have mother board and CPU esp32 board connected with DIP connector (see pictures) , so i can reduce level of harmincs pics , except in connector aroud clk pin.
-i tried to shape the rising and falling edge of my clock without increasing the rise and fall time with capacitor 20pF but the result its worst .
iam using a buffer in the output of oscilator to avoid esp32 during boot to enter into flash mode.
I have probelm with odd harmonics on a my clock trace 50mhz for my ESP32 and LAN8720A, for CISPR 16 radiated emission limits.
-I tried with ferrite 1k@100Mhz, i had probelm with stability of ethernet i cant open web page.
-with another ferrite MPZ1608B471ATA00 470R@150Mhz . its looks good but in my design i have mother board and CPU esp32 board connected with DIP connector (see pictures) , so i can reduce level of harmincs pics , except in connector aroud clk pin.
-i tried to shape the rising and falling edge of my clock without increasing the rise and fall time with capacitor 20pF but the result its worst .
iam using a buffer in the output of oscilator to avoid esp32 during boot to enter into flash mode.
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