9780199339136, Chapter 1, Problem 77P

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Chapter 1, Problem 77P Step-by-step solution Step of Refer to Figure 1.23 and 1.24 in the textbook Consider voltage amplifier of transfer function, 1000 if 1 - 1000 if The transfer function is result of STC low pass and high Consider the DC gain 1000 Step of The low pass circuit transfer function 1 - The cutoff frequency is Hz 1 The high pass circuit transfer function IS 10 if The cutoff frequency is 100 Hz Step of Determine the gain of the Bode plot for the transfer function 1 1000 1+ if 1 = 1000 10 10 Take logarithm on both sides 20log 20log 1000 10 10 20log 1000 20log 20log 10 f = 20log 1000 20log 1+ 20log f 20log 20log 1000 10log 1+ 10log 10 f Step Draw the bode plot as shown in Figure 1. 1000 X: 1000 X: 900 995 Y: 995 800- 100 X: 1.009e+05 707.1 703.9 700- 500- 300- 200 X:10 X: 1.019e+06 Y:99.5 Y:97.71 100 X: Y:9.992 10 10 10 10 10 frequency (f) Figure Step of From Figure determine the gain at different Table 1 (Hz) 10 102 10 99.5 707.1 995 995 703.9 97.71 9.99 1 (dB) 39.9 56.9 59.9 59.9 56.95 39.79 19.99 0 Step of From Table 1, the maximum value of gain is 59.9 dB Cut off frequency is obtained at which the magnitude is less than 3 dB from the maximum value Determine the gain at cut off frequency Gain 59.9-3 56.9 dB Step of From table 1, at 56.9 dB the frequency is 104 Hz and for 56.9 dB the frequency is 100 From table 1, determine the Bandwidth of the amplifier. BW 100 =9.9 kHz Therefore, the bandwidth is Comments (2) Anonymous shouldnt it be 10^5-10^2 Anonymous yes. it should be 99 9 kHz