摘要:
A cache memory system and method includes a DRAM having a plurality of banks, and it also includes 2 SRAMs each having a capacity that is equal to the capacity of each bank of the DRAM. In operation, data read from a bank of the DRAM are stored in one of the SRAMs so that repeated hits to that bank are cached by reading from the SRAM. In the event of a write to a bank that is being refreshed, the write data are stored in one of the SRAMs. After the refresh of the bank has been completed, the data stored in the SRAM are transferred to the DRAM bank. A subsequent read or write to a second DRAM bank undergoing refresh and occurring during the transfer of data from an SRAM to the DRAM is stored in either the second bank or the other SRAM.
摘要:
A cache memory system and method includes a DRAM having a plurality of banks, and it also includes 2 SRAMs each having a capacity that is equal to the capacity of each bank of the DRAM. In operation, data read from a bank of the DRAM are stored in one of the SRAMs so that repeated hits to that bank are cached by reading from the SRAM. In the event of a write to a bank that is being refreshed, the write data are stored in one of the SRAMs. After the refresh of the bank has been completed, the data stored in the SRAM are transferred to the DRAM bank. A subsequent read or write to a second DRAM bank undergoing refresh and occurring during the transfer of data from an SRAM to the DRAM is stored in either the second bank or the other SRAM.
摘要:
A cache memory system and method includes a DRAM having a plurality of banks, and it also includes 2 SRAMs each having a capacity that is equal to the capacity of each bank of the DRAM. In operation, data read from a bank of the DRAM are stored in one of the SRAMs so that repeated hits to that bank are cached by reading from the SRAM. In the event of a write to a bank that is being refreshed, the write data are stored in one of the SRAMs. After the refresh of the bank has been completed, the data stored in the SRAM are transferred to the DRAM bank. A subsequent read or write to a second DRAM bank undergoing refresh and occurring during the transfer of data from an SRAM to the DRAM is stored in either the second bank or the other SRAM.
摘要:
A cache memory system and method includes a DRAM having a plurality of banks, and it also includes 2 SRAMs each having a capacity that is equal to the capacity of each bank of the DRAM. In operation, data read from a bank of the DRAM are stored in one of the SRAMs so that repeated hits to that bank are cached by reading from the SRAM. In the event of a write to a bank that is being refreshed, the write data are stored in one of the SRAMs. After the refresh of the bank has been completed, the data stored in the SRAM are transferred to the DRAM bank. A subsequent read or write to a second DRAM bank undergoing refresh and occurring during the transfer of data from an SRAM to the DRAM is stored in either the second bank or the other SRAM.
摘要:
A cache memory system and method includes a DRAM having a plurality of banks, and it also includes 2 SRAMs each having a capacity that is equal to the capacity of each bank of the DRAM. In operation, data read from a bank of the DRAM are stored in one of the SRAMs so that repeated hits to that bank are cached by reading from the SRAM. In the event of a write to a bank that is being refreshed, the write data are stored in one of the SRAMs. After the refresh of the bank has been completed, the data stored in the SRAMs are transferred to the DRAM bank. A subsequent read or write to a second DRAM bank undergoing refresh and occurring during the transfer of data from an SRAM to the DRAM is stored in either the second bank or the other SRAM.
摘要:
A cache memory system and method includes a DRAM having a plurality of banks, and it also includes 2 SRAMs each having a capacity that is equal to the capacity of each bank of the DRAM. In operation, data read from a bank of the DRAM are stored in one of the SRAMs so that repeated hits to that bank are cached by reading from the SRAM. In the event of a write to a bank that is being refreshed, the write data are stored in one of the SRAMs. After the refresh of the bank has been completed, the data stored in the SRAM are transferred to the DRAM bank. A subsequent read or write to a second DRAM bank undergoing refresh and occurring during the transfer of data from an SRAM to the DRAM is stored in either the second bank or the other SRAM.
摘要:
A method and system for refreshing a dynamic random access memory (“DRAM”) includes a pair of memory arrays for each of a plurality of banks. The DRAM includes the usual addressing and data path circuitry, as well as a refresh controller that refreshes the arrays in a manner that hides refreshes sufficiently that the DRAM can be used in place of an SRAM as a cache memory. Since only one of the arrays in each bank is refreshed at a time, the refresh controller is able to allow data to be written to the array that is not being refreshed. The refresh controller then causes the write data to be temporarily stored so that it can be written to the array of the refresh of the array has been completed. If neither array is being refreshed, the data are written to both arrays. Data are read from the arrays by first checking to determine if any of the arrays is being refreshed. If so, data are read from the array that is not being refreshed.
摘要:
A power supply for an integrated circuit has a piecewise linear operating characteristic for improved integrated circuit testing and screening. In an integrated circuit that receives an externally applied power signal, designated V.sub.CCX, and includes a power supply for generating an internal operating voltage, designated V.sub.CCR, an on-chip power supply circuit provides V.sub.CCR as a piecewise linear function of V.sub.CCX. In a first segment of such a function, V.sub.CCR approximates V.sub.CCX for efficient low voltage operations. In a second segment, used for normal operations of the integrated circuit, V.sub.CCR rises gradually with V.sub.CCX so that test results at the edges of the segment can be guaranteed with a margin for measurement tolerance, process variation, and derating. In a third segment, V.sub.CCR follows below V.sub.CCX at a predetermined constant offset. Transitions between segments are smooth due to nonlinear devices used in the power supply circuitry. When used in a dynamic random access memory integrated circuit, operation in the first segment provides data retention at low power consumption. Operation in the second segment supports speed grading individual devices with a margin for properly stating memory performance specifications. Operation in the third segment supports screening at elevated temperatures for identifying weak and defective memory devices.
摘要:
Embodiments in accordance with the present invention provide methods of forming a dual gated semiconductor-on-insulator (SOI) device. Such methods encompass forming a first transistor structure operatively adjacent a first side of the semiconductor layer of an SOI substrate. Insulator layer material is removed from the second side of the semiconductor layer, between the source/drain contact structures of the first transistor structure and a second transistor structure there formed operatively adjacent the second side of the semiconductor layer and aligned to the first transistor structure.
摘要:
Embodiments in accordance with the present invention provide methods of forming a dual gated semiconductor-on-insulator (SOI) device. Such methods encompass forming a first transistor structure operatively adjacent a first side of the semiconductor layer of an SOI substrate. Insulator layer material is removed from the second side of the semiconductor layer, between the source/drain contact structures of the first transistor structure and a second transistor structure there formed operatively adjacent the second side of the semiconductor layer and aligned to the first transistor structure.