dulam shiva

From the given question the information provided is :

Size of each Ram chip is : 256X8{meaning: each chip contains 256   

                                      memory words and each word length is 8-bits}

Total memory capacity is: 4096 bytes

To find number of chips : Total Memory capacity / Size of each Ramchip

                                          : 4096/256=16

So 16 ram chips needed to provide a memory capacity of 4096 bytes

• - -

1) How many bits will each memory address lines contains?

Sol) The total Memory capacity is : 4096 = 2¹²

        So each memory address contains 12-bits

2) How many address lines must go to each chip line ?

Sol) To select the chip we need 4-bits from the memory address of

         12-bits because we have 16 ram chips, to select each ram chip it needs minimum of 4 bits .

Example :

    (      Chip              )       (             Address  from each  chip               )  

 : from the above figure the given address specifies that  it select’s chip 11(1011) and the address bit is 90(01011010) 

3) How many line must be decoded for the chip select input  specify the size of the decoder?

Sol) we have 16 Ram chips so we need 4 –to--16 decoder to select one Ram from 16 Ram’s for each address .