Question 1:
a) Tabulate the truth table for an 8 x 4 ROM that implements the following 4 Boolean functions:
i) A (x,y,z) = ∑ (1,2,4,6)
ii) C (x,y,z) = ∑ (2,6)
iii) B (x,y,z) = ∑ (0,1,6,7)
iv) D (x,y,z) = ∑ (1,2,3,5,7)
b) Given a 32 x 8 ROM chip with an enable input, show the external connections necessary to construct a 128 x 8 ROM with 4 chips & a decoder.(L35)
c) Implement the following function using ROM.
f (a, b, c, d) = Pm (0, 1, 3, 5, 7)
Question 2:
a) Derive the PLA programming table for the combinational circuit that squares a 3-bit number. Minimize the number of product terms.
b) List of PLA programming table for the BCD –to-excess-3 code converter
c) What are the differences between PLA and PAL.
Question 3:
a) Implement the following function using ROM.
f(a, b, c) = ∑ m (0, 1, 2)
b) Draw a typical RAM cell.
c) What is the difference between PROM and EPROM.
d) What is the basic architecture of PLA?