Which of the following memories needs refresh?
A
SRAM
B
DRAM
C
ROM
D
All of the above
E
None of the above
Correct Answer: DRAM
A DRAM cell is composed of an access transistor and a capacitor. Data is stored in the capacitor as electrical charge, but electrical charge leaks over time. Therefore, DRAM must be refreshed periodically to preserve the stored data.