Module – 7 :

1Explain the differences between :

aStatic & Dynamic memories

bVolatile and Non Volatile memories

cBipolar & MOS memories

dRandom access and read only memories

eSemiconductor and magnetic memories

2Explain briefly the different type of ROMs

3Explain different types of fuse technologies that are used in PROM

4Explain why and EPROM is or is not a volatile memory

5What are the advantages of an EEPROM oven an EPROM

6What is a RAM? Draw and explain he circuit of a typical cell of bipolarRAM

7Describe the input conditions needed to read a word from a specific RAM address location

8How does a static RAM cell differ from a dynamic RAM? What are the advantages of dynamic RAM over static RAM

9A certain memory has a capacity of 16 K x 32. How many words does it store? What is the number of bits per word? How many memory cells does it contain?

10How many 16 K x 1 RAMs are required to achieve a memory word capacity of 16 K and a word length of 8 bits?

11To expand the 16 K x 8 memory to a 32 K x 8 organisation, how many more 16 K x 1 RAMs are required?

12What is the hex address range for 4 K x 8 ROM with hex addresses starting from 6000H

13How many memory locations are there for address values from C000 to C3FF?

14A certain memory stores 8K sixteen bit words. How many data input and data output lines does it have? How many address lines does it have? What is its capacity in bytes?

15A ROM has 11 address lines and 8 data lines. Calculate

aThe number of bits stored

bThe organisation of the memory

16Figure below shows the basic block diagram of 1024 x 1 RAM. Draw a diagram to show how four such RAMs could be connected to give a 1024 x 4 memory.

17a) A ROM has 12 address lines. Calculate the number of memory locations

b) A ROM is organized as 8 K x 8. List the function of the necessary IC

pins. What is the minimum number of pins required?

c) A 64 bit square memory matrix is addressed by the binary number

110100. In which row and in which column is the wanted location?

18a) A RAM has 4096 addressable locations. How many address pins does

it have? If there are four date input/ output pins what is the organization

of the RAM? What other pins are also required?

b)Explain the functions of the CS and R / W pins on a RAM chip.

Why does a ROM not have an R / W pin? Why is a decoder employed

in the addressing of a location in both a RAM and a ROM?

19Draw a ROM to implement the Boolean functions

F = ABCD + ABCD + ABCD + ABCD

G = AB + AB

Where letters in bold denotes complement

20A DRAM has inputs CS (chip select), OE (output enable), WE (write enable). Write down the truth table showing the functions of the device

21Briefly state the differences between

(a)SRAM, DRAM, EDO DRAM, BEDODRAM, VRAM, NOVRAM, and FRAM.

(b) ROM, PROM, EPROM, EEPROM, and flash ROM

21Draw figures to show how

a)Four 1K x 1 DRAMs can be connected together to form a 1K x 4

memory

b)Four 1K x 8 DRAMs can be connected to form a 4K x 8 memory

22A ROM has 15 address pins

a)How many words can it store?

b)A ROM can store 128K words. How many addresses must it have?

23A number of 32 K x 4 DRAMs are available. How many must be interconnected to form (a) A 512 K x 16 memory. (b) A 1M x 8 memory?

24(a) A memory is organized as 1M x 4. Calculate

(i) The number of locations in the memory

(ii) the total umber of bits stored.

(b)Repeat for 64K x 16 memory

25a) express in hexadecimal the lowest and the highest addresses of a (i) 32 x 4 EEPROM and (ii) a 1M x 4 DRAM

b) Calculate the size of each address

26Design a 64 x 16 memory using 64K x 4 ICs. The start address is 0H

27Implement the Boolean functions

F1 = ABCD + ABCD + ABCD,

F2 = ABCD + ABCD

F3 = ABCD + ABCD + ABCD + ABCD, using a ROM

The letters in bold indicates complement