Why SDRAM1 and SDRAM2 have the same pins
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‎2021-11-20 12:06 PM
Hello,
can someone please help me,
why do when i use SDRAM1 and then add SDRAM2 the data and address pins are the same but only the chip enalbe. does this mean that all pins even the Data pins DQ can be connected parallel for both chips? have someone a reference design that uses both SDRAM controllers in the same time. Thanks in advance.
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‎2021-11-20 04:34 PM
That's why you have chip selects, otherwise they'd use too many pins.
Perhaps you need a HW Design Engineer on your team?
https://community.st.com/s/question/0D50X0000BNtpmlSQB/parallel-sdram
Up vote any posts that you find helpful, it shows what's working..
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‎2021-11-21 02:07 AM
Hello Tesla, thank you again for the support.
Please one more thing, so should i use 2 times 22Ohm resistors for the same pin from each sdram then connect them to MCU or one 22Ohm resistor is enough so the node will go to bothe sdrams?
for your question about the HW Design Engineer, it not easy to get everything when you are at the beginning.
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‎2021-11-21 12:37 PM
Inline resistors are there for signal integrity, which will be dependent on your specific layout and environment. Generally, if the traces are short, you don't need inline resistors on data lines.
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