Cálculo de Resistências e Corrente

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Step of 7 8.092P Refer to Figure P8.92 from the text book. (a) Calculate the value of the current R Here, = since R (1) Therefore, the expression for the current VBE Step of Consider the expression for the difference in the values of the base to emitter voltages of transistors and In Substitute 0.7 V for 25 mV for 1 mA for and 10 for 0.585 V Therefore, the value of the voltage is 0.585 V Step of 7 Recall equation (1) R Substitute 0.585 V for and 10 for 0.585 10 R 0.585 R Therefore, the value of the resistance R is Step of (b) Calculate the value of the transcondutance Substitute 25 mV for and 10 for 8m 25 m 0.4 mA/V Therefore, the value of the transconductance is 0.4 Step of 7 Calculate the value of the resistance 8m Substitute 0.4 mA/V for 8m and 100 for 100 0.4m Therefore, he value of the resistance is Step of 7 Calculate the value of the resistance Substitute 40 V for and 10 for 40 =4MQ Therefore, he value of the resistance is 4MQ Step of 7 Consider the expression for the output resistance. Substitute 4 MQ for for 0.4 mA/V for and for R = = 308.5k = =(19.964)(4 M) Therefore, the value of the output resistance is 79.856