Review for Fun II Test 1

Fun II Topics for Test 1 Op Amp Abstraction- circuit model Inverting and non-inverting amplifiers Sum and Difference amplifiers. Integrator and Differentiator Comparator and Schmidt Trigger Op Amp Limits – voltage, current, frequency Signal Manipulation Phasors Trigonometric and Exponential Fourier Series Input-output systems Linearity and Memory FFT

If VCC and VEE are +/- 10V respectively, and R1 and R2 are each 20K ohms, which of the following is true? A. If V3 is a sinusoidal source of magnitude 1 volt and 0 degrees phase, Vout is a sinusoidal waveform of the same amplitude and 180 degrees phase. If V3 is a sinusoidal source of magnitude 1 volt and 0 degrees phase, Vout is a sinusoidal waveform of the same amplitude and phase. If V3 is a sinusoidal source of magnitude 1 volt and 0 degrees phase, Vout is -1 Volt. If V3 is a sinusoidal source of magnitude 11 volts, the output will be a sinusoidal waveform of 5.5 Volts

If VCC and VEE are +/- 10V respectively, and R1 = 1K, R2 = 20K, which of the following is true? A. The maximum input signal that can be amplified without distortion is 0.1 volts, with an output of 20 V volts Pk.-Pk. The maximum input signal that can be amplified without distortion is 0.5 volts magnitude. The maximum undistorted output is 10 volts amplitude and the phase is the same as the input voltage. A square wave cannot be suitably amplified by this circuit unless the amplitude is less than 0.1 volts.

Input Signal If R1 = 1K, R2 = 9K, V3 = 0.25 V, and the signal voltage is a 1.1V amplitude sinusoid at 1 KHZ. VCC= VEE = +/- 10V. Which Plot best depicts the output? C A B D

Suppose that the input signal is a sinusoid at 2 KHz Suppose that the input signal is a sinusoid at 2 KHz. Which is a reasonable setting for the horizontal scale on the oscilloscope, assume that you wish to display several cycles of the output in a readable fashion and that there are 10 horizontal divisions across the display? 200 nS per division 200 µS per division 2 mS per division 200 mS per division

Suppose the input voltages and resistors are configured such that the magnitude of the Fourier series of the output signal is given in the Figure above. Which of the following is true? A. The circuit is non-linear and the gain from Signal_Voltage to Vout is 2. B. The circuit is linear and the gain from Signal_Voltage to Vout is 2. C. The circuit is nonlinear and the amplitude of the fundamental frequency component of Vout is 2. D. The circuit is linear and the amplitude of the fundamental frequency components of Vout is 2.

  Suppose you need to generate a simple square wave using a single opamp driven with a noise-free sinusoidal input. Which of the following will always work, regardless of the input amplitude? A single opamp with one input biased at 0 volts and the sinusoid applied to the other input and no feedback. A single opamp with negative feedback, and the sine wave applied to the non-inverting input. A single opamp with positive feedback as long as the magnitude of the trip points are greater than the magnitude of input sinusoid. None of the other answers is correct.

Suppose you need to generate a simple square wave using a single opamp driven with a noise-free sinusoidal input. Which of the following is true about the system? The system is linear and memoryless. The system is nonlinear and memoryless. The system is linear and has memory. The system is nonlinear and has memory.

Suppose you need to generate a simple square wave using a single opamp driven with a noise-free sinusoidal input. Let the input be precisely Vin(t)=sin(π 1000 t). Consider the trigonometric FS of the output signal. Which statement is true? bn = 0 for all n an = 0 for all n Both bn = 0 and an = 0 for all n. None of the other answers is correct.

Suppose you need to generate a simple square wave using a single opamp driven with a noise-free sinusoidal input. Let the input be precisely Vin(t)=sin(π 1000 t). Consider the trigonometric FS of the output signal. For the FS in the question above, the fundamental frequency is: 500 HZ 1000 HZ 2000 HZ None of the other answers is correct.

R1 is 10 Ω and carries a current of 1 ampere. R2 is 5 Ω R1 is 10 Ω and carries a current of 1 ampere. R2 is 5 Ω. What current is supplied by I1, the DC current source? 3 amps 5 amps 2 amps None of the other responses is correct.

For each of the three systems described below determine if it is linear and if it has memory: Rubric: A: Yes B: No C: Cannot tell A system with input x(t) and output y(t)= x(0) + x(t). Linear Memory An ordinary light switch, where the input is the force with which the switch is pressed, and the output is the amount of light produced. A second order passive RLC circuit driven by an input voltage Vin(t) and measuring as output the voltage drop across the capacitor. Assume the components have zero energy stored before the input is applied.

Suppose you measure the output y(t) of a system to input x(t) = cos(ω0t). (a) If y(t) = cos(2ω0t + π/2), what does that tell you about the linearity of the system? If the system is linear, what can you tell me about H(s)? (b) If y(t) = 2 cos(ω0t + π/2), what does that tell you about the linearity of the

A periodic signal x(t) has period T = π and complex exponential Fourier series given by D1 = D−2 = j, D−1 = D2 = −j with all other Fourier series coefficients equal to zero. Find x(t).

Let a signal 𝑥 𝑡 =−­4 cos 𝜋𝑡 2 ­−5sin⁡(𝜋𝑡/7 + 𝜋 /4) Let a signal 𝑥 𝑡 =−­4 cos 𝜋𝑡 2 ­−5sin⁡(𝜋𝑡/7 + 𝜋 /4) . Which statement is true? The magnitude of the fundamental frequency is 42+52 The fundamental frequency is π/2 and the magnitude of the 7th harmonic is 5. The fundamental frequency is π/14 and the magnitude of the 7th harmonic is 4. The fundamental frequency is π and the magnitude of the 1/7th harmonic is 5. None of the other answers is correct.

A periodic signal x(t) is uniformly sampled at a constant rate such that 64 samples are collected and placed in a vector. The FFT of this vector is a vector we call FFT_x. Which of the following is true: The first element of FFT_x approximates the DC value of x(t) and the second approximates the positive fundamental frequency component of the FS. The first element of FFT_x is exactly the DC value of x(t) and the second is exactly the positive fundamental frequency component of the FS. The first element of FFT_x/64 approximates the DC value of x(t) and the second approximates the positive fundamental frequency component of the FS.

For the op-amp circuit in the figure below, find the value of V0 For the op-amp circuit in the figure below, find the value of V0. You can assume that both op-amps are operating as ideal op-amps.