The document is a seminar presentation by Debasish Dutta on semiconductor memory, covering its introduction, history, types, and conclusion. It explains various types of memory such as cache memory, random access memory (SRAM, DRAM), and read-only memory (PROM, EPROM, EEPROM), including their characteristics and uses. Additionally, it discusses the advancements in memory technology and mentions other semiconductor devices like USB flash drives and SSDs.

1. SEMINAR
ON
SEMICONDUCTOR MEMORY
BY DEBASISH DUTTA

2. CONTENTS
1. INTRODUCTION
2. HISTORY
3. TYPES OF SEMICONDUCTOR MEMORY
1. CACHE MEMORY
2. RANDOM ACCESS MEMORY
1. SRAM
2. DRAM
3. READ ONLY MEMORY
1. PROM
2. EPROM
3. EEPROM
4. CONSLUSION
5. BIBLOGRAPHY

3. INTRODUCTION
• Computer memory is the storage space where computer store data is
to be processed and instructions required for processing
• Memory is divided into large number of smaller parts called cell. Each
cell location has a unique address which varies from zero to minus
one.
• Like if the memory has 32k memory, then this memory unit has
32,768 memory location. Their address varies from 0 to 32,765.

4. HISTORY
• First computer used
thousands of octal-
base radio vacuum
tubes in 1940s
• Introduced Cathode
Ray Tubes by late
1940s
• By 1960s transistor-
based memory with
a magnetic core are
being developed

5. TYPES OF SEMICONDUCTOR MEMORY
VOLTILE MEMORY
• Cache Memory
• Random Access Memory
NON-VOLATILE MEMORY
• Random Access Memory

6. Cache Memory
• Fastest type of memory but also the
most expensive
• Its speed match with the processor
speed so as to maximize the processing
speed
• Processor can use it to store frequently
accessed data and program instruction
• Its access time is much lower as to other
types
• Its capacity is very limited

7. Random Access Memory
• It constitutes of the CPU for storing data, program, and program
result
• It has a set of memory chips, each of them is made up of Ics
• They are volatile i.e data is lost when power gets cut off
• Usage: Holds data from input devices or storages ready for processing

9. RAM
SRAM
• Use flip-flop to store each bit of
memory so does not need to be
periodically refreshed
• Faster and consumes low power
• Expensive and have complex
structure(6 transistors per bit)
• Transistors do not leak charges
do need not have to be
refreshed periodically.
DRAM
• Store each bit of memory in
capacitor in an IC
• Real capacitors leak charges so
capacitors need to be changed
periodically
• Simple Structure( 1 transistor
and 1 capacitor per bit) so has
very high density

11. Read Only Memory
• Its contents are fixed when
manufactured
• Holds the bootstrap loader part
of the operating system
• Retains its data when the power
is cut off i.e non-volatile
PROM
• They are empty when
manufactured
• Programmed by the user
• Once programmed the data
cannot be erased

12. ROM
EPROM
• Erasable Programmable Random
Access Memory
• Uses UV light to clear data
• Special PROM Programmer is
used to write
• PROM burner is used to remove
its data using UV light
EEPROM
• Electrically Erasable
Programmable Random Access
Memory
• Uses IC as array of floating-gate
transistors
• Can be Programmed in-circuit,
by applying special programming
signals.
• Most preferred mode of ROM

13. ROM

14. CONCLUSION
• Some other semiconductor memory include like USB Flash Drives,
Flash Memory Devices like SSDs, Micro Memory Cards, etc.

15. BIBLOGRAPHY