Hello all,

I have tried to work at this problem for a while but I am having some trouble with it. Here is the given multi-part question and I will discuss what I have done so far.

a)

\(f_{0} = 10 kHz -> w0 = \frac{1}{RC} = 2*pi*f_{0} -> C = 1/(2*pi*f_{0}*R) = 1.59 nF\)

\(Gain = 1 + \frac{R_{2}}{R_{1}} = 2.2 -> R_{2} = 1.2*R_{1} = 6k \)

b) KCL @ V- ?

\(\frac{V_{o} - V_{d,on} - V_{-}}{R_{3}} + \frac{V_{o} - V_{-}}{R_{2}} = \frac{V_{-}}{R1}\)

\(V_{-} = \frac{V_{o}}{3}\)

\(V_{o} = \frac{(30M)V_{d,on}}{(14k)R_{3} + 60M}\)

c)

d)

Wondering if anyone can check my solutions and help me out. Thanks!

I have tried to work at this problem for a while but I am having some trouble with it. Here is the given multi-part question and I will discuss what I have done so far.

*Design a Wienbridge Oscillator using the circuit configuration shown. Assume that the voltage supply to the op-amp is +/- 10 V and that the diode turn-on voltage, Vd,on is 0.7 V. The oscillation frequency required is 10 kHz and the output amplitude is 5 V. Select R1 = 5 kΩ, R = 10 kΩ and set hte gain of the circuit at the start of oscillations to be 2.2.***a) Determine the value of C and R2.**

b) Write an expression for the output voltage given the conditions shown in the figure.

c) Determine the value of R3 that provides the output amplitude of 5 V.

d) Accurately draw two cycles (periods) of the output waveform vs. time. Carefully labelling the drawing.b) Write an expression for the output voltage given the conditions shown in the figure.

c) Determine the value of R3 that provides the output amplitude of 5 V.

d) Accurately draw two cycles (periods) of the output waveform vs. time. Carefully labelling the drawing.

__My solutions:__a)

\(f_{0} = 10 kHz -> w0 = \frac{1}{RC} = 2*pi*f_{0} -> C = 1/(2*pi*f_{0}*R) = 1.59 nF\)

\(Gain = 1 + \frac{R_{2}}{R_{1}} = 2.2 -> R_{2} = 1.2*R_{1} = 6k \)

**Not sure though...**b) KCL @ V- ?

\(\frac{V_{o} - V_{d,on} - V_{-}}{R_{3}} + \frac{V_{o} - V_{-}}{R_{2}} = \frac{V_{-}}{R1}\)

\(V_{-} = \frac{V_{o}}{3}\)

**Solve for Vo... Not sure if this is correct as it doesn't take into account the other diode direction...**\(V_{o} = \frac{(30M)V_{d,on}}{(14k)R_{3} + 60M}\)

c)

**Not sure...**d)

**5 Vpp sinewave with a frequency of 10 kHz...**Wondering if anyone can check my solutions and help me out. Thanks!

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