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Step 1 of 11 2.075P Refer instrumentation Figure Write expression for differer instr Substitute 2R, R2 and for =1+2(10) =1+20 Therefore the differential gain, amplifier Step 2 of 11 From shown Figure 2.20 the textbook equal voltage appears the input terminals amp and op amp causing com mon mode output voltage equal the common mode gain, instrumentation amplifier 0 V/V Step 3 of 11 expression (CMRR) CMRR Substitute 21 V/V for V/V for in the equation CMRR rejection -ratic Step reduce resistor values and by 1% increase resistor values 2R, and 1% The resistor values are, Calculate differential of the instrumentation amplifier 1.01R, 198 =(0.98)(1+19.6) Therefore 20.19 V/V Step 5 of 11 Consider state amplifier shown Figure 1. Figure Step 6 of 11 formula (1) Assume al resistors R, The range of the range of Step 7 of 11 R2 To obtain maximum common mode gain select R2 R1 Substitute and in the equation 2x% 2x% 100 50 x% Therefore the worst case common-mode gain, 50 Step 8 of 11 Calculate worst-case common-mode gain for x=1% 50 - 50 =0.02 V/V Therefore case mode gams 0.02 V/V Step 9 of 11 Calculate rejection-ratio CMRR Substitute V/V and 0.02 V/V equation CMRR 0.02 dB mode ratio, Step 10 of 11 The value resistor, 2R, Calculate the differential gain the umentation amplifier Substitute for 2R, and R, =1+200 Therefore the of the 201 V/V Step 11 of 11 the common- mode same Therefore the mode gain, 0.02 V/V Calculate common-mode rejection Substitute 201 V/V and 0.02 V/V for in the equation 201 0.02 =20(4) =80 dB Therefore the common rejection -ratio CMRR is 80 dB for high differential gain high CMRR achieved