Magnetic random access memory with dynamic random access memory (DRAM)-like interface
View Patent ↗A memory device includes a magnetic memory unit for storing a burst of data during a burst write operation. Each burst of data includes sequential data units with each data unit being received at a clock cycle, and written during the burst write operation, wherein the burst write operation is performed during multiple clock cycles. Further, the memory device includes a mask register coupled to the magnetic memory unit that generates a write mask during the burst write operation to inhibit or enable data units of write data. Furthermore, the memory device allows a next burst write operation to begin while receiving data units of the burst of data to be written or providing read data.
1. A memory device configured to emulate dynamic random access memory (DRAM) comprising:
a memory array including a plurality of memory cells organized into rows and columns, at least one row of memory cells comprising a plurality of pages that store bursts of data during burst write operations, each burst of data including sequential data units that are written to a page;
a mask register coupled to said memory array and configured to generate write masks for said burst write operations; and
a control circuit operable to:
initiate a burst write operation that writes a burst of data to said memory array, said burst write operation spanning multiple clock cycles; and
after receiving one or more data units of said burst of data by said memory array, allow a subsequent burst write or read command to begin before completion of said burst write operation in progress.
2. The memory device of claim 1 further comprising:
a data latch coupled to said memory array, said data latch configured to latch a page of data in response to an array read operation and configured to output a latched data burst in said burst write operation; and
a write buffer configured to receive said latched data burst and provide said burst of data for writing to said memory array.
3. The memory device of claim 2 , wherein while another burst write operation accessing a first location within another page of data is in progress, said memory device is operable to receive another burst read command initiating reading from a second location within said another page of data, said memory device being operable to continue executing said another burst write operation and to provide data associated with said another burst read operation from said data latch.
4. The memory device of claim 1 , wherein said memory array is made of a non-volatile memory.
5. The memory device of claim 1 , wherein said memory array is made of magnetic random access memory (MRAM).
6. The memory device of claim 1 , wherein said memory array is made of spin torque transfer magnetic random access memory (STTMRAM).
7. The memory device of claim 1 , wherein a write operation takes longer than a read operation.
8. The memory device of claim 1 , wherein said memory device is compliant with at least one version of double data rate (DDR) SDRAM Specification.
9. The memory device of claim 1 , wherein said memory device is compliant with at least one version of low power double data rate (LPDDR) Specification.
10. The memory device of claim 1 , wherein a version of double data rate (DDR) scheme is employed during burst write and burst read operations.
11. The memory device of claim 10 , wherein a double data rate 3 (DDR3) scheme is employed during burst write and burst read operations.
12. The memory device of claim 1 , wherein a version of low power double data rate (LPDDR) scheme is employed during burst write and burst read operations.
13. The memory device of claim 12 , wherein a low power double data rate 2 (LPDDR2) scheme is employed during burst write and burst read operations.