This section of the MIG Design Assistant focuses on the Self Refresh with Suspend Operation, as it applies to the MIG Spartan-6MCB designs.Note: This Answer Record is a part of the Xilinx MIG Solution Center (Xilinx Answer 34243). The Xilinx MIG Solution Center is available to address all questions related to MIG. Whether you are starting a new design with MIG or troubleshooting a problem, use the MIG Solution Center to guide you to the right information.
The Spartan-6 family offers the suspend mode, an advanced static power-management feature, which reduces FPGA power consumption while retaining the FPGA configuration data and maintaining the design. The Spartan-6 device can quickly enter and exit suspend mode as required in an application.Using the Spartan-6 FPGA suspend mode with the DRAM self refresh feature allows you to realize significant power savings during longer periods with no memory access. For additional information on the suspend mode, see the Spartan-6 FPGA Power Management User Guide(UG394).
There are two recommended methodsfor using the Suspend Mode capabilities of Spartan-6 devices with designs containing an MCB-based interface:"Suspend Mode with DRAM Data Retention" and"Suspend Mode without DRAM Data Retention".The following section descibes the "Suspend Mode with DRAM Data Retention" method. Additional details on this method as well as the"Suspend Mode without DRAM Data Retention" method can be found the in the "Suspend" section of "Chapter 4: MCB Operation" in the the Spartan-6 FPGA Memory Controller User Guide(UG388).
Suspend Mode with DRAM Data Retention
During suspend mode,the Spartan-6 retains FPGA configuration data and the state of the FPGA application.This is one of the key properties that enables this method.Several other conditions have to be met for the"Suspend Mode with DRAM Data Retention" method to work properly.
Suspend mode with DRAM data retention is supported in MIG 3.8 and newer designs.