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Altera_Forum
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16 years ago

Fpga ethernet voltage levels

Hey everybody, I am transmitting ONLY from the FPGA without PHY chip ( are implemented the basic PHY functions on the FPGA ), also i am using isolation ( transformer ). The fpga Cyclone I ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

10BASE-T is in fact sending a digital level from the PHY output to the filter, so it can be emulated by logic gates. You should have series resistors to match the line impedance, so the output level is already halved and isn't much above nominal ethernet send level. You need about 100 - 200 mV sensitivity on receive, however.