Difference Between SRAM & DRAM

Difference between Static RAM & Dynamic RAM

SRAM

1. Stores

bits

in

DRAM

memory

cells

capacitors and transistors.

composed of flip flops. 2. Each cell which can store a single

bit

1. Memo Memory ry cells cells are are comp compos osed ed of 

requires

six

2. Eac Each cell ell requi equire res s a capac apacit itor or (which stores bit as charge) & a transistor.

transistors. 3. Does Does not not need need to be refr refres eshe hed d

3. Need Needs s to be refr refres eshe hed d ever every y

periodically as flips flops retain

few millisec milliseconds onds to retain retain data

the data.

because

4. Faster Faster acc access ess time time comp compare ared d to DRAM, therefore used as caches

5. Low Low densi ensity ty/l /les ess s memo memory ry per per due

to

more

circuitry

of

the

capacitor leaks. 4. Slower Slower acce access ss time time comp compare ared d to

6. More More powe powerr cons consum umpt ptio ion n than than because

of

low

chip

density. 7. More More costl costly y in term terms s of cos costt per bit compared to DRAM due to low chip density.

being refreshed. 5. High High chip chip densit density/m y/more ore memo memory ry per chip compared to SRAM due

required for a single cell.

DRAM

charge

SRAM as it cannot be read while

mostly.

chip

the

to less circuitry for a single cell. 6. Less Less powe powerr cons consum umpt ptio ion n than than SRAM

because

of

simple

circuitry. 7. Less Less cost costly ly than than SRAM SRAM beca becaus use e of

high

chip

dens ensity

and

therefore used as main memory in PCs.