Will Kinetis K64/K66 support a Gigabit PHY?

[stejfish]

I'm planning to use either K64 or K66 with Ethernet, and in addition to the standard 10/100BaseT speeds, there is a chance that we may be asked to support a 1000BaseT Ethernet connection. Is there any reason why we can't connect a PHY which supports 1000BaseT to either K64 or K66? I recognize that the MCU itself may not be able to support processing large data transfers at those speeds, but as long as the PHY supports the MII interface and the speed, it will still connect at 1000BaseT if that is what the Ethernet switch supports, right? We're considering micrel KSZ* PHYs.

Thanks in advance,

sf

[ndavies · Accepted solution]

No, it doesn't work that way. Both your Mac and PHY have to operate at the same speed. The PHY doesn't have any way to convert 1Gbs to 100Mbs.  The fastest any PHY connected to a Kinetis will be able to go is 100 Mbs. The switch will connect to the 100 Mbs.

[stejfish]

Thanks Norm for response!