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Atmega, USB 3.0, USB 2.0, I2C - Noise?

-=Hulk=-

New Member
Hello

I'm trying to design a PCB which will host a M.2 LTE Modem and antenna just behind.
I need to avoid EMI as much as possible, but I don't have any scope to make measurements .
So I'm trying to follow the best practices.

The board has the following IC and buses:
- Atmega @8MHz with external oscillator
- INA260 current/voltage sensors, I2C 100kbps
- Temp/humidity SI7013 sensor, I2C 100kbps
- IMU, I2C 100kbps
- LTC4367 overvoltage protection IC with charge-pump (400kHz???) to drive the Mosfet
- USB 3 + USB 2 Mux (2.5GHz and 48MHz)
- SIM Card MUX (1-4MHz)
- 1-Wire bus

So, my questions?
- Would it be a good idea to use a tin shield can over that stuff? Or would the tin can harm the performances of the LTE antenna located just behind (800-2600MHz)
- Is it useful to add a ferrite bead on the Vcc line of the ICs, to avoid escaping of high frequency noise?

Thank you
 

ronsimpson

Well-Known Member
Most Helpful Member
Is it useful to add a ferrite bead on the Vcc line of the ICs, to avoid escaping of high frequency noise?
The ICs need a capacitor from Vcc to ground at the power pin. Then you can add a bead if you want.
Would it be a good idea to use a tin shield can over that stuff? Or would the tin can harm the performances of the LTE antenna located just behind (800-2600MHz)
The antenna needs to be outside the can. If the can works it would also keep the RF signal inside the can.
 

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