(LAN8710) oscillator - asking for recomendation

Embedded Linux Discussions
1

Hi all,
I have a custom board based upon Beaglebone Black. I am using Octavo OSD3358 and two Microchip LAN8710 PHY. The PHYs are wired RMII so I need a 50mhz clock. Because of my dual ethernet design, there will be a total of four clock signals that need supplied.
PHY-1 CLKIN (pin-5)
OSD3358 RMII1_REFCLK (pad H18)
PHY-2 CLKIN (pin-5)
OSD3358 RMII2_REFCLK (pad H16)

Is one crystal capable of providing four clock inputs?
Can you provide a link to a reference design using one crystal and four clock inputs?

I may want to use a oscillator instead of a crystal.
Can you recommend a manufacture and part number of an oscillator that is a good match for the LAN8710 and OSD3358?
Same questions,
Is one oscillator capable of driving all four clock inputs?
Do you have a reference design using oscillator(s)?

Thank you,

2

Crystals have to be driven, and so are usually only directly connected to a single device, lest one end up with some number (N) different driver circuits arguing with one another.

Oscillators integrate the drive hardware and provide a buffered output, which is more practical to use more than once. One invites signal integrity issues when doing so however; use of a clock fanout buffer or similar device is advisable so as to have a clean transmission line between signal source and sink.

I’ve not seen a reference design for doing what you ask, though this doesn’t mean that such a thing is nonexistant.