2 The BJTs in a differential amplifier are wired in the: Select one of ... A) common base connection. B) common collector connection. C) common emitter connection. D) grounded emitter connection.

3 Common mode is when: Select one of ... A) the two inputs receive the same signal. B) the two collector resistors are equal in value. C) the two inputs receive different signals. D) both inputs are grounded.

4 What is the common mode gain of an amplifier in which the emitter resistor has double the resistance of the collector resistors? Select one of ... A) 1. B) –0,5. C) 0.25. D) 2.

5 If the two inputs of an amplifier are 25 mV and 35 mV, and the output is 1.25 V, the differential gain is: Select one of ... A) 1.25. B) 50. C) –0.002. D) 125.

6 What is meant by 'differential mode' Select one of ... A) The output equals the differential (rate of change) of the input. B) The output is proportional to the difference of the inputs. C) One input is grounded. D) The inputs are equal.

7 If the common mode gain is 2.5 and the differential gain is 57.5, the CMRR is: Select one of ... A) 60. B) 23. C) 55. D) 57.5 mV.

8 Express the CMRR of Q.7 in decibels. Select one of ... A) 27.23 dB. B) –23 dB. C) 34.81 dB. D) 13.62 dB.

9 The differential gain is proportional to: Select one of ... A) the common mode gain. B) only the negative voltage. C) the gain of the transistors. D) the current through the 'tail' resistor.

10 The advantage of having a constant current sink instead of a 'tail' resistor is that it: Select one of ... A) stabilises the output voltage. B) gives a larger common mode gain. C) it needs less current than a normal 'tail' resistor. D) can make the CMRR larger.