OPENCORES.ORG

Hi Dipak,
FPGA's come in different speed grades.  So within one family, you might have 
four different speed grades for the same part number and package. I am not 
sure about Xilinx, but with Altera FPGA's the lower the -X the faster the 
FPGA. The speed is specified in terms of the tpd (pin-to-pin delay) 
parameter in the FPGA datasheet. This affects the maximum operating 
frequency of your design in that particular FPGA.

Hope this helps,

Regards

Rohit
----- Original Message ----- 
From: "Dipak Modi" <dipakm@e...>
To: <ASICDESIGN@y...>; "Discussion list about free open source IP 
cores" <cores@o...>
Sent: 09 September 2004 12:15
Subject: [oc] FPGA speed grade

Hi All,

What does speed grade in FPGA part name signifies?
Say xilinx part name: XC3S50 -4 PQ G 208 C, So how this -4 term is
related with the FPGA speed?

Thanks,

Dipak

_______________________________________________
http://www.opencores.org/mailman/listinfo/cores