# Morris Mano Edition 3 Exercise 4 Question 16 (Page No. 150)

1 vote
91 views

A BCD to seven segment decoder is a combinational circuit that converts a decimal digit in BCD to an appropriate code for the selection of the segments in the display indicator used for displaying the decimal digit in the familiar form. The seven output of the decoder(a,b,c,d.e.f) selects the corresponding segments in the display c as shown in figure (a). The numeric designation chosen to display the decimal digit is shown in Fig (b).

Design the BCD to Seven-segment decoder using the minimum number of the NAND gates.

the Six invalid combinations should result in a blank display.

 Decimal A B C D a b c d e f g 0 0 0 0 0 1 1 1 1 1 1 0 1 0 0 0 1 0 1 1 0 0 0 0 2 0 0 1 0 1 1 0 1 1 0 1 3 0 0 1 1 1 1 1 1 0 0 1 4 0 1 0 0 0 1 1 0 0 1 1 5 0 1 0 1 1 0 1 1 0 1 1 6 0 1 1 0 1 0 1 1 1 1 1 7 0 1 1 1 1 1 1 0 0 0 0 8 1 0 0 0 1 1 1 1 1 1 1 9 1 0 0 1 1 1 1 1 0 1 1 10 1 0 1 0 $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ 11 1 0 1 0 $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ 12 1 1 0 0 $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ 13 1 1 0 1 $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ 14 1 1 1 0 $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ 15 1 1 1 1 $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$ $\phi$

$\phi: \text{Don't care}$

## Related questions

1
65 views
Design a combinational Circuit that converts a binary number of 4-bits to decimal number in BCD. Note that the BCD number is the same as the binary number as long as the digit is 9 or less than 9. binary numbers from 1010 to 1111 converts into BCD numbers from 1 0000 to 1 0101.
The adder-subtractor circuit of figure has the following values for mode input M and data inputs A and B. In each case, determine the values of the outputs: $S _ 4 S _3 S _2 S _1$ and $C _5$. M A B 0 0111 0110 0 1000 1001 1 0101 1000 1 0000 1010