Analog Electronics interview questions

1. A.RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output
2. B.forward voltage at which a junction diode begins to conduct appreciably, about 0.7 V for silicon and 0.3 V for germanium, after which current rises exponentially
3. C.operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs
4. D.capacitance between the input and output of an inverting stage appears at the input multiplied by (1 + |gain|), which sets the upper cut-off of a common-emitter amplifier

Answer + AI explanation with Pro

1. A.Miller effect
2. B.Negative feedback
3. C.Diode cut-in voltage
4. D.Wien bridge oscillator

Answer + AI explanation with Pro

1. A.Diode cut-in voltage — RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output
2. B.Diode cut-in voltage — capacitance between the input and output of an inverting stage appears at the input multiplied by (1 + |gain|), which sets the upper cut-off of a common-emitter amplifier
3. C.Diode cut-in voltage — condition for sustained oscillation: loop gain magnitude exactly unity and total phase shift around the loop 0° or an integer multiple of 360°
4. D.Diode cut-in voltage — forward voltage at which a junction diode begins to conduct appreciably, about 0.7 V for silicon and 0.3 V for germanium, after which current rises exponentially

Answer + AI explanation with Pro

1. A.returning a fraction β of the output in antiphase to the input divides gain by (1 + Aβ) while extending bandwidth by the same factor and cutting distortion and drift
2. B.RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output
3. C.reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference
4. D.operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs

Answer + AI explanation with Pro

1. A.Diode cut-in voltage
2. B.Zener diode
3. C.Miller effect
4. D.BJT active region

Answer + AI explanation with Pro

1. A.Zener diode — RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output
2. B.Zener diode — returning a fraction β of the output in antiphase to the input divides gain by (1 + Aβ) while extending bandwidth by the same factor and cutting distortion and drift
3. C.Zener diode — forward voltage at which a junction diode begins to conduct appreciably, about 0.7 V for silicon and 0.3 V for germanium, after which current rises exponentially
4. D.Zener diode — reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference

Answer + AI explanation with Pro

1. A.reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference
2. B.condition for sustained oscillation: loop gain magnitude exactly unity and total phase shift around the loop 0° or an integer multiple of 360°
3. C.operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs
4. D.returning a fraction β of the output in antiphase to the input divides gain by (1 + Aβ) while extending bandwidth by the same factor and cutting distortion and drift

Answer + AI explanation with Pro

1. A.Negative feedback
2. B.MOSFET saturation region
3. C.Wien bridge oscillator
4. D.BJT active region

Answer + AI explanation with Pro

1. A.BJT active region — returning a fraction β of the output in antiphase to the input divides gain by (1 + Aβ) while extending bandwidth by the same factor and cutting distortion and drift
2. B.BJT active region — operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs
3. C.BJT active region — capacitance between the input and output of an inverting stage appears at the input multiplied by (1 + |gain|), which sets the upper cut-off of a common-emitter amplifier
4. D.BJT active region — reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference

Answer + AI explanation with Pro

1. A.capacitance between the input and output of an inverting stage appears at the input multiplied by (1 + |gain|), which sets the upper cut-off of a common-emitter amplifier
2. B.RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output
3. C.BJT biasing with a base divider and emitter resistor whose negative feedback holds the Q-point nearly independent of β, provided divider resistance is well below β·RE
4. D.condition for sustained oscillation: loop gain magnitude exactly unity and total phase shift around the loop 0° or an integer multiple of 360°

Answer + AI explanation with Pro

1. A.Barkhausen criterion
2. B.Voltage-divider bias
3. C.MOSFET saturation region
4. D.Diode cut-in voltage

Answer + AI explanation with Pro

1. A.Voltage-divider bias — reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference
2. B.Voltage-divider bias — operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs
3. C.Voltage-divider bias — BJT biasing with a base divider and emitter resistor whose negative feedback holds the Q-point nearly independent of β, provided divider resistance is well below β·RE
4. D.Voltage-divider bias — condition for sustained oscillation: loop gain magnitude exactly unity and total phase shift around the loop 0° or an integer multiple of 360°

Answer + AI explanation with Pro

1. A.region where VDS exceeds VGS − Vt so the channel pinches off and drain current depends only on gate voltage, making the device a voltage-controlled current source for amplifiers
2. B.operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs
3. C.BJT biasing with a base divider and emitter resistor whose negative feedback holds the Q-point nearly independent of β, provided divider resistance is well below β·RE
4. D.forward voltage at which a junction diode begins to conduct appreciably, about 0.7 V for silicon and 0.3 V for germanium, after which current rises exponentially

Answer + AI explanation with Pro

1. A.Miller effect
2. B.Voltage-divider bias
3. C.MOSFET saturation region
4. D.Zener diode

Answer + AI explanation with Pro

1. A.MOSFET saturation region — forward voltage at which a junction diode begins to conduct appreciably, about 0.7 V for silicon and 0.3 V for germanium, after which current rises exponentially
2. B.MOSFET saturation region — region where VDS exceeds VGS − Vt so the channel pinches off and drain current depends only on gate voltage, making the device a voltage-controlled current source for amplifiers
3. C.MOSFET saturation region — reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference
4. D.MOSFET saturation region — BJT biasing with a base divider and emitter resistor whose negative feedback holds the Q-point nearly independent of β, provided divider resistance is well below β·RE

Answer + AI explanation with Pro

1. A.forward voltage at which a junction diode begins to conduct appreciably, about 0.7 V for silicon and 0.3 V for germanium, after which current rises exponentially
2. B.returning a fraction β of the output in antiphase to the input divides gain by (1 + Aβ) while extending bandwidth by the same factor and cutting distortion and drift
3. C.reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference
4. D.operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs

Answer + AI explanation with Pro

1. A.BJT active region
2. B.Miller effect
3. C.Voltage-divider bias
4. D.Negative feedback

Answer + AI explanation with Pro

1. A.Negative feedback — BJT biasing with a base divider and emitter resistor whose negative feedback holds the Q-point nearly independent of β, provided divider resistance is well below β·RE
2. B.Negative feedback — returning a fraction β of the output in antiphase to the input divides gain by (1 + Aβ) while extending bandwidth by the same factor and cutting distortion and drift
3. C.Negative feedback — reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference
4. D.Negative feedback — condition for sustained oscillation: loop gain magnitude exactly unity and total phase shift around the loop 0° or an integer multiple of 360°

Answer + AI explanation with Pro

1. A.operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs
2. B.RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output
3. C.condition for sustained oscillation: loop gain magnitude exactly unity and total phase shift around the loop 0° or an integer multiple of 360°
4. D.BJT biasing with a base divider and emitter resistor whose negative feedback holds the Q-point nearly independent of β, provided divider resistance is well below β·RE

Answer + AI explanation with Pro

1. A.BJT active region
2. B.Miller effect
3. C.MOSFET saturation region
4. D.Barkhausen criterion

Answer + AI explanation with Pro

1. A.Barkhausen criterion — condition for sustained oscillation: loop gain magnitude exactly unity and total phase shift around the loop 0° or an integer multiple of 360°
2. B.Barkhausen criterion — reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference
3. C.Barkhausen criterion — operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs
4. D.Barkhausen criterion — region where VDS exceeds VGS − Vt so the channel pinches off and drain current depends only on gate voltage, making the device a voltage-controlled current source for amplifiers

Answer + AI explanation with Pro

1. A.region where VDS exceeds VGS − Vt so the channel pinches off and drain current depends only on gate voltage, making the device a voltage-controlled current source for amplifiers
2. B.reverse-biased diode operated deliberately in breakdown so it holds a nearly constant voltage, serving as a shunt regulator or voltage reference
3. C.capacitance between the input and output of an inverting stage appears at the input multiplied by (1 + |gain|), which sets the upper cut-off of a common-emitter amplifier
4. D.operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs

Answer + AI explanation with Pro

1. A.Zener diode
2. B.Voltage-divider bias
3. C.Miller effect
4. D.Wien bridge oscillator

Answer + AI explanation with Pro

1. A.Miller effect — condition for sustained oscillation: loop gain magnitude exactly unity and total phase shift around the loop 0° or an integer multiple of 360°
2. B.Miller effect — capacitance between the input and output of an inverting stage appears at the input multiplied by (1 + |gain|), which sets the upper cut-off of a common-emitter amplifier
3. C.Miller effect — returning a fraction β of the output in antiphase to the input divides gain by (1 + Aβ) while extending bandwidth by the same factor and cutting distortion and drift
4. D.Miller effect — RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output

Answer + AI explanation with Pro

1. A.RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output
2. B.region where VDS exceeds VGS − Vt so the channel pinches off and drain current depends only on gate voltage, making the device a voltage-controlled current source for amplifiers
3. C.returning a fraction β of the output in antiphase to the input divides gain by (1 + Aβ) while extending bandwidth by the same factor and cutting distortion and drift
4. D.forward voltage at which a junction diode begins to conduct appreciably, about 0.7 V for silicon and 0.3 V for germanium, after which current rises exponentially

Answer + AI explanation with Pro

1. A.Negative feedback
2. B.Wien bridge oscillator
3. C.Barkhausen criterion
4. D.MOSFET saturation region

Answer + AI explanation with Pro

1. A.Wien bridge oscillator — BJT biasing with a base divider and emitter resistor whose negative feedback holds the Q-point nearly independent of β, provided divider resistance is well below β·RE
2. B.Wien bridge oscillator — region where VDS exceeds VGS − Vt so the channel pinches off and drain current depends only on gate voltage, making the device a voltage-controlled current source for amplifiers
3. C.Wien bridge oscillator — operating region with the base-emitter junction forward biased and base-collector reverse biased, where collector current is β times base current and amplification occurs
4. D.Wien bridge oscillator — RC oscillator using a lead-lag network in positive feedback, oscillating at 1/(2πRC) and requiring an amplifier gain of exactly 3 for audio-frequency sine output

Answer + AI explanation with Pro