column address strobe
Abbreviated as CAS, a signal, or strobe, sent by the processor to a DRAM circuit to activate a column address. DRAM stores data in a series of rows and columns, similar in theory to a spreadsheet, and each cell where a data bit is stored exists in both a row and a column. A processor uses CAS and RAS (row address strobe) signals to retrieve data from DRAM. When data is needed, the processor activates the RAS line to specify the row where the data is needed, and then activates the CAS line to specify the column. Combined, the two signals locate the data stored in DRAM.