3.12 DRAM

• Memory devices that store binary data by charging the gate capacitance of MOS transistors that therefore need to be refreshed periodically so as not to lose the charge when present 

3.11 Static RAM

• Semiconductor RAM memory device that consist essentially of FF registers and the necessary circuitry for decoding. Information will remain valid as long as power is on

3.10 RAM Architecture

• RAM typically come with word capacities of 1K, 4K, 8K, 16K or 64K and word size of 1, 4 or 8 bits

3.9 Semiconductor RAMs

• RAMs are used in computers for temporary storage of programs and data (volatile)

3.8 ROM Applications

• Firmware
• Bootstrap Memory
• Data Tables
• Data Converter
• Auxiliary storage

3.7 Flash Memory

• Nonvolatile memory IC that has the high-speed access and in-circuit eras-ability of EEPROMs but with higher densities and lower cost

3.6 Types of ROM

• Mask-Programmed ROM - requires manufacturer to load data using photographic negative technique
• Programmable ROM (PROM) - can be programmed once by the user
• Erasable Programmable ROM (EPROM) - can be erased and reprogrammed multiple time with UV light
• Electrically Erasable PROM (EEPROM) - can be erased and reprogrammed multiple time with voltage