Calculation of Input Impedance of AX2000 and series termination

Status
Not open for further replies.

rhnrgn

Member level 5
Joined
Dec 25, 2013
Messages
92
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,288
Activity points
2,069
Hello,

I will use AX2000 fpga in my new design. I will use 100 MHz oscillator.

Oscillator's output specs:


FPGA's datasheet:
https://www.google.com.tr/url?sa=t&...VzLNmzRidByEgIQ&bvm=bv.98197061,d.bGg&cad=rja

Question:

If i am not wrong, output impedance of oscillator is around 100 Ohm. I need to calculate input impedance of HCLK pin of AX2000 in order to understand should i use series termination or not.

If input impedance of HCLK pin is 100 Ohm, i dont need series termination resistor. Just use trace with 100 Ohm character in 100Mhz and direct connect oscillator to fpga in shortest path. But if input impedance of FPGA is 50 Ohm then i need something more.

Can you please tell me how to calculate input impedance of HCLK pin? And also if i have any wrong idea?

Best Regards
 

Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…