1. DRAM in Personal Computes
Richard L. Goldman
©February 1, 2001

2. Evolution of Popular Types of PC DRAM
DRAM – Dynamic RAM
FPM DRAM – Fast Page Mode Dynamic RAM
Paging
Bursting
Interleaving
EDO DRAM – Extended Data Out Dynamic RAM
BEDO DRAM – Burst EDO Dynamic RAM
SD RAM – Synchronous Dynamic RAM
DRD RAM – Direct Rambus Dynamic RAM
DDR RAM – Double Data Rate RAM

3. 5-5-5-5 1 2 3 4 5 6 7 8 9 Standard DRAM 1. Select Row 2. Select Column
A B C D E F G H I J K L M N 1 2 3 4 5 6 7 8 9
1. Select Row
2. Select Column
3. Transfer Data

4. 5-3-3-3 1 2 3 4 5 6 7 8 9 FPM DRAM Paging 1. Select Row
A B C D E F G H I J K L M N 1 2 3 4 5 6 7 8 9
1. Select Row
2. Select Column
3. Transfer Data

5. 1 2 3 4 5 6 7 8 9 FPM DRAM Bursting 1. Select Row 2. Select Column
A B C D E F G H I J K L M N 1 2 3 4 5 6 7 8 9
1. Select Row
3. Transfer Data

6. FPM DRAM Interleaving
A B C D E F G H I J K L M N
A B C D E F G H I J K L M N 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9
1. Select Row
1. Select Row
2. Select Column
2. Select Column
3. Transfer Data
3. Transfer Data

7. 5-2-2-2 1 2 3 4 5 6 7 8 9 EDO DRAM 1. Select Row 2. Select Column
A B C D E F G H I J K L M N 1 2 3 4 5 6 7 8 9
1. Select Row
3. Transfer Data

8. 5-5-5-5 1 2 3 4 5 6 7 8 9 BEDO DRAM 1. Select Row 2. Select Column
A B C D E F G H I J K L M N 1 2 3 4 5 6 7 8 9
1. Select Row
3. Transfer Data