Subelement E: Digital Logic— Topic 38: Memory
Question 3-38E5
Element 3 (GROL)How many individual memory cells would be contained in a memory IC that has 4 data bus input/output pins and 4 address pins for connection to the address bus?
Explanation
In a memory IC, the number of address pins determines the total number of unique memory locations, while the number of data pins indicates how many bits each location can store.
With 4 address pins, the IC can access $2^4 = 16$ distinct memory locations. Each of these locations is capable of storing a "word" of data.
The 4 data bus input/output pins signify that each memory location (or word) is 4 bits wide.
To find the total number of individual memory cells (bits), multiply the number of locations by the number of bits per location:
Total cells = (Number of locations) $\times$ (Bits per location)
Total cells = $16 \times 4 = 64$ cells.
Therefore, the memory IC contains 64 individual memory cells.
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