SDRAM routing guidelines

Status
Not open for further replies.
P

pcb87

Member level 1
Joined
Oct 24, 2007
Messages
40
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Activity points
1,529
Hi all,

I am working with a pcb with 4 SDRAM chips (TSSOP package) .Data, address ,control and and clock are connected to all the 4 SDRAM chips. What is the routing strategy that i should follow.What should be the length of the signals.


Thanks in advance
 

Hi marce,

Datasheet doesnt specifies anything about routing guidelines. I have done pcb's with DDR SDRAMs . I think SDRAM s are not that critical as DDRs. Do i need to follow the same guidelines for DDR.
 

Hi PCB87,
First,Group the signal (address,data and control signal) like For Address (0-7 signal with BA0 and BA1) for Data signal (0-7) with DQ signal.Route the DQ signal first after that route the data signal.set the min and max in tool let me know which tool r u using
 


Hi Kapil,

I am using Cadence allegro. Memory chip am using is SDRAM not DDR .It doesnt have the data strobe, there's only data and mask signals.There are 4 SDRAM chips.
 

Hi,
First group the signal address and data signal Address (Addr0-12) data BUS 1(Data0-7 and DM0,DQS0) Data Bus2 (8-15 with DM1 and DQS1)and control signal (CAS,CS0,CS1,RAS,WE,BA0,BA1) set in constraint Manager

- - - Updated - - -

after that route the signal for data signal reference length is strobe signal you have match the length matching according to the data strobe.

- - - Updated - - -

for your reference follow this https://www.edaboard.com/threads/283545/#post1307462
it may be helpful for you
 

Hi Kapil ,

Thanks for that, But i have a few doubts.
What should be the minimum length of the data signals and address signals?
Is the clock length greater than data sig?
Do i need to route address ,data and control sig in same length.

Can u post the placement of DDR in any of your pcbs?


Thanks in advance
 

hi still i am not familiar in DDR better post your placement i will try to help
 

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…