QUALCOMM Incorporated
Compute-in-memory (CIM) employing low-power CIM circuits employing static random access memory (SRAM) bit cells, particularly for multiply-and-accumluate (MAC) operations

Abstract:

Low-power compute-in-memory (CIM) systems employing CIM circuits that include static random access memory (SRAM) bit cells circuits. The CIM circuits can be used for multiply-and-accumulate (MAC) operations. The CIM circuits can include five-transistor (5T) SRAM bit cells that each have a single bit line coupled to an access circuit for accessing the SRAM bit cell for read/write operations. The CIM circuit also includes a multiplication circuit (e.g., an exclusive OR (XOR)-based circuit) coupled to the SRAM bit cell. The CIM circuit is configured to perform multiplication of an input data value received by the multiplication circuit with a weight data value stored in the SRAM bit cell. The reduction of an access circuit in the 5T SRAM bit cell allows the pull-up voltage at a supply voltage rail coupled to the inverters of the 5T SRAM bit cell to be reduced to reduce standby power while providing storage stability.