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Figure below shows a circuit suitable for op-amp applications. For all transistors β = 100, VBE = 0.7 V, and ro = ∞. a) For inputs grounded and output held at 0 V (by negative feedback) find the collector currents of all transistors. Neglect base currents. b) Calculate the input resistance. c) Calculate the gain of the amplifier with a load of 5 kΩ. d) With load as in (c) calculate the value of the capacitor C required for a 3-dB frequency of 100 Hz.

Figure below shows a circuit suitable for op-amp applications. For all transistors β = 100, VBE = 0.7 V, and ro = ∞. a) For inputs grounded and output held at 0 V (by negative feedback) find the collector currents of all transistors. Neglect base currents. b) Calculate the input resistance. c) Calculate the gain of the amplifier with a load of 5 kΩ. d) With load as in (c) calculate the value of the capacitor C required for a 3-dB frequency of 100 Hz.

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  1. (20 marks) Figure below shows a circuit suitable for op-amp applications. For all transistors β = 100 , V B E = 0.7 V , and r o = ∞ . a) For inputs grounded and output held at 0 V (by negative feedback) find the collector currents of all transistors. Neglect base currents. b) Calculate the input resistance. c) Calculate the gain of the amplifier with a load of 5 k Ω . d) With load as in (c) calculate the value of the capacitor C required for a 3-dB frequency of 100 H z .

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