1. wnopp 20001 Memory device Introduction n Memory Cell n Memory Word n Byte n Capacity n Address n Read Operation n Write Operation n Access Time n Volatile Memory n Random-Access Memory (RAM) n Sequential-Access Memory (SAM) n Read/Write Memory (RWM) n Read-Only Memory n Static Memory Device n Dynamic Memory Device n Internal Memory n Mass Memory

2. wnopp 20002 General Memory Operation n Select the address. n Select R/W operation. n Supply the input to be store (W operation). n Hold the output data comings from memory (R operation). n Enable (or Disable) the memory Example Memory chip 2K x 8. How many total bits can chip store? 2K = 1 x 1024 = 2048 words 1 word = 8 bits 2K x 8 = 2048 x 8 = 16384 bits Which memory store the most bits: 5M x 8, 1M x 16 5M x 8 = 5 x 1,048,576 x 8 = 4,1943,040 bits 1M x 16 = 1,048,576 x 16 = 1,677,7216 bits

3. wnopp 20003

4. 4 CPU- Memory connections Write operation 1. CPU ๐ Binary address on address bus. 2. CPU ๐ Data on data bus. 3. CPU ๐ control signal. 4. ICs decode address location. 5. Transfer data to the selected location. Read operation 1. CPU ๐ Binary address on address bus. 2. CPU ๐ control signal. 3. ICs decode address location. 4. Place data ๐ data bus ๐ Transfer data to CPU

5. wnopp 20005 Read-Only Memory

6. wnopp 20006 ROM architecture

7. wnopp 20007 ROM timing read operation PROMs fusible links

8. wnopp 20008 Structure of a bipolar MROM (Mask-Programmed )

9. wnopp 20009

10. 10 Example of a programmable logic device

11. wnopp 200011 PROM architecture for PLDs

12. wnopp 200012 PAL architecture

13. wnopp 200013

14. wnopp 200014 Cell arangement in 16Kx1 DRAM Symbolic representation of DRAM Symbol & mode table for 6264 SRAM

15. wnopp 200015

16. wnopp 200016

17. wnopp 200017

18. wnopp 200018