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BJT Circuit

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This is for a 0.1 mA collector current with beta typical = 72. Minimum Beta is 40 and maximum beta = 120. Please see the attached image for circuit diagram.

Provide a suitable network at the emitter to provide a voltage gain of 100, and provide input and output capacitors as well as the emitter network to operate as low as 100 Hz with gain greater than 70. What are the input and output impedances above 100 Hz and how much can they vary? Do you need to specify a minimum load to achieve the required performance?

What is the maximum operating frequency of the amplifier with a 1 KOhm source resistance driving it? What is the approximate maximum output voltage (peak to peak) available?

Add a simple network, a parallel capacitor, to the output to reduce the 3 dB bandwidth to 10 kHz. What value capacitor is needed? What is the maximum noise of the amplifier referred to the input? Also at the output? How does this compare with the typical value from the (attached) data sheet?

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BJT Circuit and Maximum Range of Collector Voltage

1. Choose values of R1, R2, Rc and Re to give 1 volt at the emitter and 5 volts at the collector for a typical beta transistor with 1 mA collector current at room temperature, and state them. What is the collector voltage with your values for a minimum typical device, a maximum current gain device, and at 100 °C for a typical device ? Estimate the maximum range of collector voltage, for a typical device at room temperature, which results from using 5 % tolerance resistors.
Calculate the effect of changing Vcc to +15 Volts with no other changes in the circuit components. Will it still operate?

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