Hi,
My customer is considering to use the TPD8F003 for Ethernet@10Mbit/s, RS-485@480kbit/s, and CAN@250kbit/s communication .
TPD8F003 has a resistor 100Ω for the filter.
Does this resistor affect for the each communication?
I'm sorry if this question is inappropriate for this forum.
Thanks,
Kuramochi
Kuramochi ,
The effect of the 100 Ω R in the filter is attenuation. Due to a voltage dropping across the resistor when there is any current in the signal, the insertion loss starts out at some attenuation. An example is the insertion loss graph in the data sheet, it starts out at -6 dB at 0 Hz and thus any signal is attenuated to one half its voltage, or one-fourth its power. I do not believe that this will work with the PHY.
The below schematic shows two typical placements for EMI/ESD protection devices for ethernet. The circled "A" and "B" are where an RLC networks are put to reduce EMI. The "A" area is where we have some TVSs designed for ESD protection, but we do not have any EMI reduction devices for here. The "B" area is between the magnetics and the connector where the ESD/surge protection must be much more robust and we have not designed any product for this space.
Regards,
