
634 Microwave Engineering
In regard to the storage mechanism, the data in a memory may be stored
either in ip-op or as a charge on a capacitor. These memory cells are called
static and dynamic, respectively. In static memory, data are retained as long
as the supply voltage is retained. The dynamic memory requires periodic
refreshing to compensate for the loss of charge due to leakage. The static
RAM (SRAM) and dynamic RAM (DRAM) memories belong to the above
two categories. RWMs use active circuitry to store information; thus, they are
referred to as volatile memories. In these, the data are lost when the supply is
removed. SRAM and DRAM memo ...