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Ferrite Beads

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I'm working with a ENC28J60 IC (Ethernet controller) that requires a ferrite bead "rated for at least 80mA" for EMI reduction (from the datasheet). I've been using a Murata SMD (Mouser: 81-BLM21BB600SH1D ) with the following specs:
Impedance:      60 Ohms      
Tolerance:    25 %    
Maximum DC Current:    200 mAmps    
Maximum DC Resistance:    0.2 Ohms
Test Frequency:      100 MHz

I'd like to change it to a through-hole part, however all through hole parts are in the multiple A and mOhm range.

Since I'm not sure how the maximum DC current and resistance are related to the effectiveness of the filter I wanted to ask here if something like the Panasonic EXC-ELS ferrite (Mouser: 667-EXC-ELSA35V) will be suitable replacement. Specs:
Impedance:      50 Ohms      
Maximum DC Current:    7 Amps    
Maximum DC Resistance:    10 m Ohms
Test Frequency:      100 MHz

From my reading it seems like the Impedance and size of the ferrite are what matter for the filter, but the reference design in the datasheet doesn't mention anything about that.


EDIT: Ooops, that was for the beginners forum... sorry :)

Looks ok to me.

Slightly lower impedance at 100 MHz.

Thanks qno. There are also 80Ohm versions of it, will that be the better choice?

Since this is the projects forum I'll make the topic a bit more relevant. The project is a dual avr board with RTC, PH circuit, Ethernet circuit and port expander for LCD. It is going to be a Reef tank controller. I will post the schematic when I get home. Project is open source.

If you're just using it for fun instead of an actual project then you can just replace the ferrite with a piece of wire, which I have before with the ENC28J60.  Obviously you shouldn't do this in a proper design as it won't conform to specs, but for non-commercial it's fine.

Well it is mainly for fun, but also for others to benefit, so the goal is to be as good as we can make it :)

Seems like the 50 Ohm ferrite will do the job.



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