$4.$ The circuit below is a $\backslash (4\backslash$times $4\backslash )$ block of NAND$-$type ROM.

$($a$)$ Configure it to store the data shown in the table below by adding NMOS transistors at proper positions with proper connections in the block.

$($b$)$ Describe and explain the read operation procedures, say, to read the bits stored in WL$[2].$

$($c$)$ How will you size the PMOS transistors?

$($d$)$ Describe and explain an advantage and a disadvantage of the NAND$-$type ROM compared with the NOR$-$type ROM.

WI

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WI