Hi, Those resistors would serve the purpose of purpose of being series termination resistors for these critical signals. What this does is to ensure that these signals that appear at the SDRAM are clean signals with overshoot, undershoot, ringing within limits. Else you would have errors in the data transfer to/from memory. The reason why especially they are applied to these signals is because if you ensure these signals are clean you have margin on the Address/ data signals to settle down as the clock signals etc are clean The value of the resistor is chosen such that the sum of the value of series resistor and the source resistance of the output driver of the processor is equal to the value of the trace impedance on the board. This is part of transmission line theory and is to ensure that the reflections of the signals and hence overshoot, undershoot are minimal. Rgds Louis -----Original Message----- From: Nico Weling [mailto:eedniwe@e...] Sent: Monday, October 27, 2003 5:48 PM To: pci@o... Subject: [pci] Resistors on Insight MEMEC Board Hi, I know that some of you are using the Insight's MEMEC development board to run the PCI bridge. On the second revision of this board there are four resistors in series in signal CASn, RASn, WEn and CLK of the SDRAM component. Does someone know the reason for doing this? Why especially to those signals? What values should they have (11 ohm)? Any help is apreciated. Regards, Nico. dear louis

Information contained in this E-MAIL being proprietary to Wipro
Limited is
'privileged' and 'confidential' and intended for use only by the
individual
or entity to which it is addressed. You are notified that any use,
copying
or dissemination of the information contained in the E-MAIL in any
manner
whatsoever is strictly prohibited.