Hi Expert,
Now I design a new automotive gateway, use DP83TG720R-Q1 as Gigabit PHY and connect to IFX Aurix TC39x MCU via RGMII interface.
Beside the standard RGMII signals, the AURIX TC399 needs a 125MHz reference clock called GREFCLK for the RGMII Interface. By default, this clock will be generated a crystal oscillator or generated by the Ethernet PHY or Switch (see below diagram).
I noticed the CLKOUT pin in DP83TG720R-Q1 datasheet, it only output 25MHz referance clock, so it cannot used as GREFCLK in Aurix TC39x.
I found an alternative that using Sync Ethernet could outputs a 125 MHz clock that is based on the copper receive path when linked up, so did the DP83TG720R-Q1 support the feature? I compared other OEM Gigabit PHY, like Marvell and Realteck, they all support this feature.
Also could you any TI information or learning materials about what is Sync Ethernent and associated application in automotive, thanks!
