Abstract: A method is described for controlling refresh of a multibank DRAM. A refresh request and associated address are generated external to the DRAM. DRAM refresh operations are initiated in one bank while data transfer operations are being executed in another bank. The refresh request is handled much like a memory read request, with the associated read data being ignored. In one implementation, the refresh request is given priority over any other pending memory access request. By initiating refresh operations without first waiting for all DRAM banks to be precharged, the significant time penalties associated with the prior art are avoided.

Abstract: An apparatus is described for interleaving bank and page access to a multibank memory device, such as an SDRAM or SLDRAM. An address detector detects a pending page access, and the associated data transfer request is then stored in a page hit register. A control timing chain includes a rank register queue with a bank access input, a page write input, and a page read input. Comparator circuitry provides bank address comparisons to avoid bank conflicts and to control the timing of insertion of the page hit register contents into the appropriate page write or page read input. While a pending page access request is stored in the page hit register, other pending bank access operations can be initiated. Consequently, bank and page accesses can be interleaved in substantially contiguous command cycles, and data transfer bandwidth is correspondingly improved.

Abstract: A method is described for interleaving bank and page access to a multibank memory device, such as an SDRAM or SLDRAM. An address detector detects a pending page access, and the associated data transfer request is then stored in a page hit register. A control timing chain includes a rank register queue with a bank access input, a page write input, and a page read input. Comparator circuitry provides bank address comparisons to avoid bank conflicts and to control the timing of insertion of the page hit register contents into the appropriate page write or page read input. While a pending page access request is stored in the page hit register, other pending bank access operations can be initiated. Consequently, bank and page accesses can be interleaved in substantially contiguous command cycles, and data transfer bandwidth is correspondingly improved.

Abstract: A method is described for interleaving bank and page access to a multibank memory device, such as an SDRAM or SLDRAM. An address detector detects a pending page access, and the associated data transfer request is then stored in a page hit register. A control timing chain includes a rank register queue with a bank access input, a page write input, and a page read input. Comparator circuitry provides bank address comparisons to avoid bank conflicts and to control the timing of insertion of the page hit register contents into the appropriate page write or page read input. While a pending page access request is stored in the page hit register, other pending bank access operations can be initiated. Consequently, bank and page accesses can be interleaved in substantially contiguous command cycles, and data transfer bandwidth is correspondingly improved.

Abstract: An apparatus is described for interleaving bank and page access to a multibank memory device, such as an SDRAM or SLDRAM. An address detector detects a pending page access, and the associated data transfer request is then stored in a page hit register. A control timing chain includes a rank register queue with a bank access input, a page write input, and a page read input. Comparator circuitry provides bank address comparisons to avoid bank conflicts and to control the timing of insertion of the page hit register contents into the appropriate page write or page read input. While a pending page access request is stored in the page hit register, other pending bank access operations can be initiated. Consequently, bank and page accesses can be interleaved in substantially contiguous command cycles, and data transfer bandwidth is correspondingly improved.

Abstract: An apparatus is described for controlling refresh of a multibank DRAM. A memory controller includes refresh request circuitry having a refresh counter and address incrementer. The refresh counter produces a refresh request signal, with the address incrementer producing an associated refresh address. The refresh request and address are handled much like a memory read operation, with the associated read data being ignored. In one implementation, the refresh request is given priority over any other pending memory access request. Refresh operations are initiated without first waiting for all DRAM banks to be precharged, thereby avoiding the significant time penalties associated with the prior art.