We are connecting an SGMII port of the 66AK2H12 to a 1000Base-KX port across a VPX backplane thru AC coupling caps. The 1000Base-KX is a 1.25Gbps SERDES version of gigabit Ethernet (per IEEE 802.3-2008). The 1000Base-KX has transmitter characteristics of 800 to 1600 mV differential peak-to-peak output voltage. The IEEE standard also recommends using only 4.7nF AC coupling caps (to reduce inrush current in the receiver).
My questions are:
1) What is the absolute voltage ratings and recommended operating voltage range for SGMII differential receiver inputs? The K2 Serdes guide says it conforms to LVDS. But I'd like to know the specific K2 ratings.
2) Is 4.7nF AC coupling caps sufficient for the K2? The K2 documentation recommends 100nF.
3) When will the K2 Hardware Design guide be released?
thanks.