一个RAM芯片的容量为1024个字，每个字8位(1K×8)。从1K×8 RAM构成16K×16 RAM所需的2×4带使能线的解码器的数量为
(A) 4
(B) 5
(C) 6
(D) 7答案： (B)
解释：
RAM chip size = 1k ×8[1024 words of 8 bits each]
RAM to construct =16k ×16
Number of chips required = (16k x 16)/ ( 1k x 8)
= (16 x 2)
[16 chips vertically with each having 2 chips
horizontally]
So to select one chip out of 16 vertical chips,
we need 4 x 16 decoder.
Available decoder is 2 x 4 decoder
To be constructed is 4 x 16 decoder
Hence 4 + 1 = 5 decoders are required.这个问题的测验