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Dose DM6437 DDR_CKE pin need to have an external pull-down resistor?

Hi Champs,

According to XILINX Answer Records #36104, CKE signal is required an external pull-down with a 4.7 kOhm resistor connected to GND to adhere to the DDR2 Spec to drive it to low during RESET as below.

  o XILINX AR# 36104
    (http://www.xilinx.com/support/answers/36104.html)

    - Description

      The Memory Controller drives the ODT, CKE, and RESET signals during normal operation
      and LOW during initialization, but a pull-down with a 4.7 kOhm resistor connected to
      GND is still required to adhere to the DDR2 and DDR3 Memory Standards.


    - Solution

      Based off the Power-Up Initialization Sequence defined by the DDR2 Spec, CKE and ODT
      are supposed to be maintained at a LOW state while applying power. To guarantee this
      occurs while the FPGA is being configured (before it can drive CKE and ODT "Low") we
      require the pull-down to GND.


So, Dose DM6437 DDR_CKE pin also need to have the 4.7 kOhm external pull-down resistor?

Thanks in advance for your cooperation.

Best regards,
j-breeze

The Memory Controller drives the ODT, CKE, and RESET signals during normal operation and LOW during initialization, but a pull-down with a 4.7 kOhm resistor connected to GND is still required to adhere to the DDR2 and DDR3 Memory Standards.