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Step of 7 1.035P Consider a 4-bit digital word The most-significant bit, b₃ is interpreted as a sign bit-0 indicates positive and 1 for negative values. By this scheme, the values are represented as shown in table 1: Table 1 4-bit digital word 0000 +0 0001 +1 0010 +2 0011 +3 0100 +4 0101 +5 0110 +6 0111 +7 1000 -0 1001 -1 1010 -2 1011 -3 1100 -4 1101 -5 1110 -6 1111 -7 As +0 and -0 are same (equal) hence zero is represented in this scheme in two ways 0000 and 1000. Step of 7 From the table 1, The minimum value of D is =-7 and the maximum value of D The change in voltage is, Write the expression for the minimum amplitude of analog signal. Substitute 0.5 V for and -7 for Dain in the equation. =-3.5-0.25 =-3.75 Step of 7 Calculate the maximum amplitude of analog signal. Substitute 0.5 V for and 7 for in the equation. =3.5+0.25 = 3.75 Therefore, the full range of the analog signal is -3.75 V to 3.75 V V to 3.75 V Step of 7 Calculate the signed-magnitude digital code for an input of +2.5 V V +2.5 = (Since, = 0.5 +5 Therefore, the signed-magnitude digital code, D for an input of +2.5V is +5=0101 Step of 7 Calculate the signed-magnitude digital code for an input of -3V -3 AV -3 = (Since, =0.5V) 0.5 Therefore, the signed-magnitude digital code, D for an input of -3V is -6=1110 Step of 7 Calculate the signed-magnitude digital code for an input of +2.7V +2.7 (Since, 0.5V) 0.5 =+5.4 Therefore, the signed-magnitude digital code, D for an input of +2.7V is +5.4=0101 Step of 7 Calculate the signed-magnitude digital code for an input -2.8 -2.8 = (Since, =0.5V) 0.5 =-5.6 Therefore, the signed-magnitude digital code, D for an input of -2.8V is -5.6=1110