RAM is a type of volatile computer memory that can be accessed randomly. It is faster than other types of memory like SSD/HDD, so programs load faster from RAM. RAM was invented in 1968 and its technology has improved over time from FPM to DDR5 RAM. There are two main types - SRAM which holds data statically but uses more power, and DRAM which must be refreshed but uses less power. The capacity of RAM in computers has increased significantly over time from 256 MB to 8 GB currently. RAM provides faster loading of programs but has the disadvantage of being volatile and space-limited.

1. Subject: RANDOM ACCESS MEMORY (RAM)
Presented by:
 MD. SHAMIM-AL-MAMUN
 Roll : PGD-0909
Mawlana Bhashani
Science and Technology University
Course Title : Computer Organization & Architecture

2. Random Access Memory

3. Index:
 Introduction
 History
 Technology
 Block Diagram
 Position and Structure
 Types of RAM
 Difference
 Capacity to store
 Advantage and Disadvantage

4. Introduction:
 Random Access Memory (RAM) is the best known from of
computer memory.
 RAM is considered as volatile memory, which means that the
stored information is lost there is no power.
 RAM is made up of small chips that from a memory module.
 Whenever you open a program, it gets loaded from the SSD/HDD
into the RAM.
 This is because reading data from the RAM is much faster than
reading data from the SSD/HDD.

5. History:
 RAM was invented by Robert
Heath Dennard
 At IBM Thomas J Watson
Research Center in 1968

6.  Technology:
Type Year
Fpm (Fast page mode) 1990
EDO (Extended data o/p) 1996
SDRAM (Single dynamic RAM) 1996
RDRAM 1998
DDR SDRAM 2000
DDR2 SDRAM 2003
DDR3 SDRAM 2007
DDR4 SDRAM 2014
DDR5 SDRAM 2020

7. Block Diagram of RAM:
 This block diagram introduces the main interface to
RAM.
 A Chip Select, CS enables or disables the RAM.
 ADRS specifies the address or location to read from or
write to.
 WR selects between reading from or writing to the
memory.
 To read from memory, WR should be set to 0

8. Position of RAM:

9. Structure of RAM:

10. Insert RAM into Socket:

11. Eject RAM into Socket:

12. Types of RAM:

13. Types of RAM:
SRAM (Static Random Access Memory)
 SRAM holds data in a static from, as long as the memory has
power.
 Each bit is stored on four transistor that froms two cross
coupled inverters.
DRAM (Dynamic Random Access Memory)
 DRAM is called dynamic because it must constantly be
refreshed and lose the data in very short time.
 DRAM stores each bot of data in a separate capacitor within a
integrated circuit.

14. Difference:
SRAM DRAM
 Requires less memory.  Requires more memory.
 Access time is low.  Access time is high.
 Do not refresh.  Need to be refresh.
 Faster access time.  Slow access time.
 More power consumption.  Less power consumption.
 Used in cache memory.  Used in main memory.

15. Capacity of RAM:
From Beginning:
 256 MB
 512 MB
 1024 MB (1 GB)
 2048 MB (2 GB)
 4096 MB (4 GB)
 8192 MB (8 GB)

16.  Advantage and Disadvantage:
 Advantage:
 Program will load much faster.
 Power Efficient that uses much less power then disk
drive.
 Disadvantage:
 Volatile: a power outage will cause irrecoverable.
 Space-limited: cost per bit is high.