Posts: 6
Registered: ‎06-08-2009

Routing DDR2 automatic or manually

Hi all,

I use cadence and would know if it s possible to route DDR2 component to virtex5
automatically (spectra)??? or is better to do it in manually.

Thank s in advance.

Avnet Employee (Star Contributor)
Posts: 511
Registered: ‎05-05-2009

Re: Routing DDR2 automatic or manually

We route the DDR2 memory interface signals manaully on our boards as they need to be length matched and routed properly to acheive the best signal integrity.

Regular Visitor
Posts: 1
Registered: ‎11-26-2010

Re: Routing DDR2 automatic or manually

Hi  ,


I suggest you to go for the Manual Routing because for memories there are few guidelines which you need to follow. That cannot be set by tools automatically.


Few guides which as to be followed.


1. Data Lines Track length and width must be same.

2.Address lines Impedance mismatch can be taken cared.

3. Clk Signals as to be routed from the Ground plane to avoid the signal integrity issues.

4. Control signals  (CKE,RAS,CAS ,.........) as to be routed properly. considering that 90 degress bending is not allowed.




Jangi Reddy