06-19-2012 11:57 PM
I am a new FPGA circuit designer. In the 'Virtex-5 FPGA PCB Designer’s Guide' datasheet,at the page of 18, there is a 'Discrete Substrate Capacitor Specifications' table. In the table, the recommended XC5VSX95T VCCINT 4.7U decoupling capacitor has the Body Size of 0805, and the type is 8-Terminal Ceramic X7S. According to my understanding, the capacitor is a four capacitors array . What I do not understand is the Body Size, is it means the whole array's size is 0805, or each capacitor size in the array is 0805. I cannot find a 0805 capacitor array that the value is 4.7u.
Looking forward to reply.
06-20-2012 12:12 AM - edited 06-20-2012 12:21 AM
Why is this of interest to you? Table 2-12 describes capacitors which are internally mounted in the FPGA packages (substrates), if my reading is correct.
If you are interested in PCB-mounted capacitors for the XC5VSX95T, your interest should be focused on Table 2-3 and Table 2-11.
-- Bob Elkind
README for newbies is here: http://forums.xilinx.com/t5/New-Users-Forum/README-first-Help-for-new-users/td-p/219369
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