RAM is used in embedded systems or any systems where the programming doesn’t need to change.

Must be provided with constant power supply. If the power is interrupted, then the data are lost

the data and instructions in PROM (Programable ROM) can be changed

in ......no special tools are required for erasure and you can erase only portions of the chip, one
byte at a time.

......Is some kind of EEROM

In …. Data can be written or erased in blocks, so it is faster

SRAM stores data as a charge on a capacitor

During writing operation, a voltage signal is applied as …. For high

During writing operation, a voltage signal is applied as …. For low

data values are transferred from the capacitor to the bit line

data values are transferred from the bit line to the capacitor

..........Destroys the bit value stored on the capacitor, so data word must be restored rewritten after each read

a ....... requires the supporting refresh circuitry

SRAM is static because stored bits do not need to be refreshed

The data bit is stored on cross-coupled inverters.

A SRAM cell is simpler and smaller than DRAM cell

DRAM Used for cache memory

Used for main memory

DRAM is … dense and … expensive than SRAM

The faster memory is, the less expensive it is per bit of storage.

To deal with this disparity, computer systems use a combination of memory types to provide the best performance at the best cost. This approach is called