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34.5. Reset and Clock Requirements
The main reset input signal to the SDRAM is treated as an asynchronous reset input from the SDRAM core perspective. A reset synchronizer circuit, as typically implemented for each reset domain in a complete SOC/ASIC system is not implemented within the SDRAM core. Instead, this reset synchronizer circuit should be implemented externally to the SDRAM, in a higher hierarchy within the complete system design, so that the “asynchronous assertion, synchronous de-assertion” rule is fulfilled.
The SDRAM core accepts an input clock at its clk input with maximum frequency of 100-MHz. The other requirements for the clock, such as its minimum frequency should be similar to the requirement of the external SDRAM which the SDRAM is interfaced to.