Question

OUESTION 1 the circle convintrod Consider the circuit diagram of an 8-bit digital-to-analogue converter (more detail regarding DACs will be introduced in SU 11- 12) below with the following component values:

Answer 1

RI I जन RRI - I6 4RI R2=10kr HY if it От 169 92 164 if 1. Dok Io giver digital to analog converter is a weighted resistor digital to analog converter. this DAC requires very carge resistance for LSB position ie hulle here n = No. of Bits given that n=8 = 281 R = 27 R=1282

kol at mode Io + I; +12+ 13+ 14 +I5 + 16 +17 = Id TorRef + Di vref 1280, 64R Iz vref + D3 vref - P4 Vref 32R, 160 gr + + Ds viref 4R, De vreet 2R, - Pq Vire of R o-ovo = R2 Vo = - Vief R2 (DoT 0; 24 D, Ž+D32 +2424 + D5 297D0+0,27) . .. iri general S tes 27 Vo = Evaet Rs o + 012 +D, +, .-942+9,22+ Dc2 + D2 27 ) ... Yo for 8 Bit DAC

where Do, Di, D, D3, D4 D5, D6, Dj are corresponding digital inputs ? K= Step voltage for Resolution rovi LSB voltage 32: veef R2.7 RJ . 27 20 27 5 volts. = 0.03906 volts. Step Voltage = 0.03906 volts . ik) in general sus Vo= k (decimal equivalent of digital inputs ,

analog output voltage for D = 11001001 Vo= a kl decimal equivalent of digital . inputs) 1 2 +2 +2+ ) r 7 6 3 . = leasett after 7.8515 8.8125 J vo= 7.8515 volts vo for De 1101111 VOH = I ( 2* +2° +2° +2° +2 +2+2+1). 9.96 volts