# The cross section of a JFET is shown in the following figure. Let VG be -2V and let Vp be the initial pinch-off voltage. If the width W is doubled (with ther geometrical parameters and doping levels remaining the same), then the ratio between the mutual trans conductance of the initial and the modified JFET is

1.  4

2.

3.

4.

4 Explanation :
No Explanation available for this question

# Consider the schmidt trigger circuit shown below A triangle wave which goes from -12V to +12V is applied to the inverting input of the OP-AMP. Assume that the output of the OP-AMP switchs from +15V to -15V. the voltage at the inverting input switches between

1.  -12V and +12V

2.  -7.5V and +7.5V

3.  -5V and +5V

4.  0V and 5V.

4

-5V and +5V

Explanation :
No Explanation available for this question

# In the following transistor circuit, VBE=0.7, re=2.3, V/IE and β and all the capacitances are very large The value of DC current IE is

1.  1mA

2.  2mA

3.  5mA

4.  10mA.

4

1mA

Explanation :
No Explanation available for this question

# In the following transistor circuit, VBE=0.7, re=2.3, V/IE and β and all the capacitances are very large The mid-band voltage gain of the amplifier approximately

1.  -180

2.  -120

3.  -90

4.  -60.

4

-60.

Explanation :
No Explanation available for this question

# In the following a stable multi vibrator circuit which properties of v0(t) depend on R2

1.  Only the frequency

2.  Only the amplitude

3.  Both the amplitude and the frequency

4.  Neither the amplitude nor the frequency.

4

Only the frequency

Explanation :
No Explanation available for this question

# In the circuit shown below, the op-amp is ideal, the transistor has VBE=0.6V and β=150. Decide whether the feedback in the circuit is positive or negative and determine the voltage V at the output of the op-amp

1.  Positive feedback, V=10V

2.  Positive feedback, V=0V

3.  Negative feedback, V=5V

4.  Negative feedback, V=2V.

4

Negative feedback, V=2V.

Explanation :
No Explanation available for this question

# Consider the CMOS circuit shown, where the For small increase in VG beyond 1 V, which of the following gives the correct description of the region of operation of each MOSFET

1.  Both the MOSFETs are in saturation region

2.  Both the MOSFETs are in triode region.

3.  n-MOSFET is in triode and p-MOSFET is in saturation region

4.  n-MOSFET is in saturation and p-MOSFET is in triode region.

4

n-MOSFET is in saturation and p-MOSFET is in triode region.

Explanation :
No Explanation available for this question

# In the silicon BJT circuit shown below, assume that the emitter area of transistor Q1 is half that of transistor Q2 The value of current I0 is approximately

1.  0.5mA

2.  2mA

3.  9.3mA

4.  15mA.

4

2mA

Explanation :
No Explanation available for this question

# The amplifier circuit shown below uses a silicon transistor. The capacitors CC and CE can be assumed to be short frequency and the effect of output resistance r0 can be ignored. If CE is disconnected from the circuit, which one of the following statements is TRUE

1.  The input resistance Ri increases and the magnitude of voltage gain Av decreases

2.  The input resistance Ri decreases and the magnitude of the voltage gain Av increases

3.  Both input resistance Ri and the magnitude of voltage gain Av decreases

4.  Both input resistance Ri and the magnitude of voltage gain Av increases.

4

The input resistance Ri increases and the magnitude of voltage gain Av decreases

Explanation :
No Explanation available for this question

# Assuming the OP-AMP to be ideal, the voltage gain of the amplifier shown below is

1.

2.

3.

4.

4 