Do the KSZ8041, KSZ8051, KSZ8061 and KSZ8081 Ethernet PHYs have the voltage mode transmit drivers?

The KSZ8051, KSZ8061, and KSZ8081 PHYs have the voltage mode transmit drivers. Both the TX pair and RX pair are internally terminated and biased, so the transformer center taps should not be connected to any biasing voltage.

Do not connect the RX center tap to the TX center tap. They should be separate, each with its own capacitor to GND. Note this also applies to KSZ9031.

KSZ8041 has the current mode transmit drivers implemented.

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