The memory size for n address lines and m data lines is given by
2022
The memory size for n address lines and m data lines is given by
- A.
\(2^{\mathrm{m}} \times \mathrm{n}\) - B.
\(\mathrm{m} \times \mathrm{n}^{2}\) - C.
\(2^{\mathrm{n}} \times \mathrm{m}\) - D.
\(\mathrm{n} \times \mathrm{m}^{2}\)
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Correct answer: C
Correct memory size: 2^n × m bits.
Step 1: n address lines produce 2^n distinct addresses (locations).
Step 2: m data lines mean each address stores m bits.
Step 3: Total memory size in bits = (number of addresses) × (bits per address) = 2^n × m.
Quick example: n = 3, m = 8 → 2^3 × 8 = 8 × 8 = 64 bits.
Why the other formulas are wrong:
2^m × n: This swaps the roles of address and data lines; the number of addresses depends on n, not m.
m × n^2: Uses n^2 for addresses, which is incorrect because address lines produce 2^n addresses, not n^2.
n × m^2: Squares the data lines and treats addresses linearly; neither step matches how memory capacity is calculated.