Reading & Writing Operation of DRAM

In Dynamic Random Access Memory CELL , transistor acts as a switch to Close (allowing current to flow) when voltage applied in address line or Open (no current flow) when no voltage applied in address line.Address Line also known as word line .Which use to signal the transistor to close or open.

During the Write operation,a voltage is applied on the bit line and a signal applied to the address line to close the transistor.Then the voltage applied on the bit line will transfer to capacitor and store in the capacitor
However the capacitor has tendency to discharge and has to refresh to maintain the bit.

While in Reading Operation ,the instruction find the bit store using the address line to read the data or bit.When the address line is selected ,the transistor turns on and the charge stored on the capacitor is fled out onto a bit line and to sense amplifier. Sense amplifiers compare the capacitor voltage to reference value to determine the logic 1 or logic 0.The read out from cell must be restored to complete the operation.