Digital Electronics Objectives Part 11

201 . The pulse width of the wave form shown is 5 ms

202 . The pulse interval is 5 ms.

203 . When the input to a seven-segment decoder is 0100, the number on display will be 4.

204 . The half adder circuit in Fig. 35 has input AB =11. The logic levels of the S and C output will be S=0, C=0.

205 . The following signals are the inputs of a 7480 full adder circuit Σ = 1 𝚺=𝟏 Ac = BC = 1 A* = B* = 1 A1 = 1 A2 = 1 B1 = 1 B2 = 1 Ci =0

Question 206 to 208 refer to Fig. 36.

The astablemultivibrator shown in Fig. 36 has R1=300 Ω and C1 =5000 pF.

206 . The pulse width is 1 microsecond

207 . The pulse interval is 1 microsecond.

208 . Frequency of the square wave at output is 500 Hz.

209 . In the above circuit if R1=500 ohm and C1=0.3 μF, the=pulse width will be 10.4 μs.

210 . The pulse interval will be 10.4 μs.

211 . The frequency will be 48.1 kHz.

212 . F = AB̅C+AB̅C̅+ABC when simplified is F = AC + A𝑩.

213 . The expression F = A̅B̅+A̅B can be simplified to F = 𝑨.

214 . Using Boolean algebra, the expression F = A𝐵CD + ABCD can be simplified to F = ACD.

215 . Using Boolean algebra, the expression F = A̅BC+ABC̅+ABC can be simplified to F = AB+BC.

216 . Using Boolean algebra, the expression F= (A+B+C+D)(A+B+𝐶+D)(𝐴+B+C+D) can be simplified as B+D+AC.

217 . Decimal number 84 in BCD code is 10000100BCD.

218 . The decimal value for the BCD coded number 00010010 is 12.

219 . Decimal 42 in XS-3 code is 01110101.

220 . Decimal number 937 in gray code is written as 110 100 100 100.