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Step of 6 13.077P Refer to Figure 12 38 in the text book for a self- biased current reference source utilizing a Widler circuit. The circuit is augmented with emitters connected to ground and bases connected to to generate constant currents of 10 and 40 respectively. Draw the Vcc V - BIASI Figure 1 Step of 6 The base-emitter voltage of the transistor is equal to that of the transistor, As Thus, the transistors and have the same emitter area. The base emitter voltage of the transistor is equal to that of the transistor In In As 10 and Thus, the emitter area of the transistor is four times the emitter area of the transistor Step of 6 Draw the circuit by connecting a resistor R6 to the emitter of and by reducing the current to 10 Vcc Q4 BIAS1 R6 Figure 2 Step of 6 Observe from the circuit that the base- emitter voltages, In = 1. 10x10 Thus, the resistance, R6 Step of 6 The output resistance of is simply Determine the resistance Ros 30 Thus, the resistance Ros is For the output resistance is increased by a factor of where = Thus, 10 0.025 The resistance is, g. 40 = 100 Step of 6 Determine the output resistance of the current source with R6 connected 30 = Thus, the output resistance of the current source with connected is Determine the resistance Thus, the output resistance of the current source is 7.06