This document discusses different types of volatile memory or RAM used in computers. It describes dynamic RAM (DRAM) which uses capacitors and must be regularly refreshed, static RAM (SRAM) which does not require refreshing but uses more transistors, and other RAM types like T-RAM, Z-RAM, and TT-RAM. RAM is used as temporary memory in a computer system to store active programs and data, and provides faster access than non-volatile storage like hard disks.

2. BATCH MEMBERS
 P.PRABAKARA PANDIAN
 K.SIMON PAULRAJ

3. OVERVIEW
 INTRODUCTION
 VOLATILE MEMORY
 RAM
 TYPES OF RAM
 DEFINITIONS
 DRAM
 SRAM
 DIFFERENCE BETWEEN SRAM AND DRAM
 TRAM
 ZRAM
 TTRAM
 ADVANTAGE OF RAM

4. INTRODUCTION
 Volatile memory also known as volatile storage
that requires power to maintain the store
information.
 Most forms of modern Random Access Memory
are volatile memory.
 Random Access Memory, or RAM, provides large
quantities of temporary storage in a computer
system.

5. VOLATILE MEMORY
 It is also known as temporary memory
because if we switch off the power the
contents in this memory will be erased.
 It is of high cost.
 It is also known as primary memory

6. MEMORY BLOCK DIAGRAM
n Data Input Lines
n
k Address Lines Memory
k Unit
2k Words
1 n Bits per Word
Read
1
Write
n
n Data Output Lines

7. BLOCK DIAGRAM OF RAM
2k x n memory
k ADRS OUT n
n DATA
CS
WR

8. RAM
 RAM stands for Random Access Memory.
 It is a form of computer data storage.
 The RAM can perform both read and write operations.
 The process of storing new information into the
memory is called read operation.
 The process of transferring the stored information out
of memory is called write operation.

9. Common RAM Types
• D-RAM
• S-RAM
• T-RAM
• Z-RAM
• TT-RAM

10. RAM
BIPOLAR MOS
SRAM SRAM DRAM

11. DEFINITIONS
SRAM
 Static random access memory uses multiple
transistors, typically four to six, for each memory cell
 but doesn't have a capacitor in each cell
DRAM
 Dynamic random access memory has memory cells
with a paired transistor and capacitor requiring

12. CMOS RAM
 CMOS RAM is a term for the small amount of memory
used by your computer and some other
 devices to remember things like hard disk settings --
see Why does my computer need a battery? for
 details. This memory uses a small battery to provide it
with the power it needs to maintain the memory
contents.

13. MEMORY CELL

14. D-RAM
 It stands for Dynamic Random Access Memory.
 It is a type of RAM that stores each bit of data in a
separate capacitor within a integrated circuit.
 The main memory in the personal computer is
Dynamic RAM
• Basic Principle: Storage of information on
capacitors.
• Charge and discharge of capacitor to change
stored value

15. DRAM(continue..)
 Common D-RAM models are
 DIP 16-pin(Dual Inline Packages)
 SIPP (Single Inline Pin Package)
 SIMM(Single Inline Memory Module)
 SIMM 30-pin
 SIMM 72-pin
 DRAM is called dynamic because it must constantly be
refreshed or it will lose the data which it is supposed to
be storing.

16. SRAM
 It stands for Static Random Access Memory.
 It is a type of semi-conductor memory where the static
indicates that unlike Dynamic RAM.
 It does not required to be refreshed periodically.
 Each bit is stored on four transistor that forms two
cross coupled inverters.

17. Memory Cell
Select
B C
S Q
C
R Q
B
RAM cell

18. DESIGN

19. SRAM
 STATIC – information stored in latches
 An S-RAM cell has three different stages.They are
 Standby
 Reading
 Writing

20. SRAM(continue..)
 S-RAM is a little more expensive,but faster and
significantly less power hungry than DRAM.
 Due to a more complex internal structure , SRAM
is less dense than DRAM.

21. DIFFERANCE
s.no SRAM DRAM
It requires low amount of It requires more memory.
1. memory.
2. Access time is low. Access time is more.
The life of data is as long as the The life of data is about four
3. power is supplied to the chip . Milliseconds.
4. Do not refresh. Needs to be refreshed.
5. More structural Less structural complexity.
complexity.

22. T-RAM
 It stands for Thyristor Random Access Memory.
 It is a new type of D-RAM computer memory
invented and developed by T-RAM semiconductor.
 It departs from the usual design of memory cells
combining the strengths of the D-RAM and S-
RAM.

23. T-RAM(continue..)
 It is produced in 32nm and 22nm.
 It is assumed that next generation processors used
this type of memory
 It has high speed and high volume.

24. Z-RAM
 It stands for ZERO-CAPACITOR Random Access
Memory.
 It is developed by innovative Silicon Based on the
floating body effect of Silicon On Insulator(SOI).
 Z-RAM licenced by Advance Micro Devices for
possible use in future microprocessor.

25. Z-RAM(continue..)
 The reduced cell size leads the Z-RAM being
faster than S-RAM used in large enough
blocks.
 It has a response time of 3ns.
 It offers equivalent speed as S-RAM but
requires less space.

26. TT-RAM
 It stands for Twin Trasistor Random Access
Memory.
 It is similar to conventional one
transistor,one capacitor as D-RAM but
eliminates the capacitor by relying on
floating body effect inherent in a Silicon On
Insulator(SOI) on manufacturing process.

27. TT-RAM(continue..)
 In this RAM memory cell, two transistors
are serially connected on an SOI substrate.
 One is an access transistor and the other is
used as a storage transistor and fulfils the
same function as the capacitor in an
conventional D-RAM cell.

28. APPLICATION OF RAM
 RAMs are utilized in the computer as scratch-
pad,buffer and main memories.
 Fast operating speed.
 Low power dissipation
 Compatibility
 Economy: MOS memories are more economical than
magnetic core for small and medium-sized systems.

29. CONCLUSION
 The memory is a major component in any computer.
 RAM is capacity and speed characteristics are
important in determine the performance of a
computer.
 So Volatile memory is the one of the main part of the
computer.
 RAM means speed of the computer , so there is no
RAM there is no speed.

31. REFERENCE
 1.Computer Organisation- Dr. M. Rajaram & Dr.P.Uma
Maheswari
 2.Digital Computer Fundamentals- Carl Hamacher & Safwat
Zaky
 3.Digital Electronics-S.Salaivahanan
 4.www.crocus_technology.com
 5.http::/hardwarehell.com
 6.http::/en.wikipedia.org