TF EIMLab9 Writeup

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Lab 9: Diode Circuits

Clipping Circuit

1.) Construct the circuit shown below using a silicon diode.

TF EIM Lab9.png

Using Diode


R= 9.6k[math] \Omega[/math]

2.) Use a sine wave generator to drive the circuit so [math]V_{in} = V_0 \cos(2 \pi \nu t)[/math] where [math]V_0 = 0.1[/math] V and [math] \nu[/math] = 1kHz. (20 pnts)

3.)Based on your observations using a oscilloscope, sketch the voltages [math]V_{in}[/math] and [math]V_{out}[/math] as a function of time.

Outoput for several input voltages near the bias point

V_{in} = 0.5V V_{in} = 0.6 V V_{in} = 0.75 V V_{in} = 0.8 V V_{in} = 1.0 V
TF EIM Lab9 P1 0.5V.png TF EIM Lab9 P1 0.6V.png TF EIM Lab9 P1 0.75V.png TF EIM Lab9 P1 0.8V.png TF EIM Lab9 P1 1.0V.png

4.)Do another sketch for[math] V_0[/math] = 1.0 V and another for 10.0 V (DONT LET ANY SMOKE OUT!). (20 pnts)

V_{in} = 1 V V_{in} = 10 V
TF EIM Lab9 P1 1V.png TF EIM Lab9 P1 10V.png

Differentiating Circuit with clipping

1.)Construct the circuit below.

TF EIM Lab9a.png

2.)Select [math]R_1[/math] and [math]R_2[/math] such that the current from the +5V DC source is less than 1.0 mA and the DC voltage at [math]V_{out}[/math] is 3 V when there is no input pulse.

[math]R_1= 15 k\Omega[/math]

[math]R_2 = 10 k \Omega[/math]

3.)Select a capacitor [math](C)[/math]and a pulse width [math]\tau[/math] to form a differentiating circuit for the pulse from the signal generator. Hint: [math]R_{12}C \ll \tau[/math].

[math]C = 10.5 nF[/math]

4.)plot [math]V_{in}[/math] and [math]V_{out}[/math] as a function of time using your scope observations. (20 pnts)

Signal setup RC fall time
TF EIM Lab9 P2 5V Signal.png TF EIM Lab9 P2 RCfallTime.png

5.) Now add the diode circuit from part 1 to prevent [math]V_{out}[/math] from rising above +5 V. Sketch the new circuit below.

6.)plot [math]V_{in}[/math] and [math]V_{out}[/math] as a function of time with the diode circuit you added using your scope observations. (the diode should clip off positive spikes)(20 pnts)

Notice the output pulse does not increase when V_{in} is increased

V_{in} = 4 V V_{in} = 7 V V_{in} =9V
TF EIM Lab9 P2 Vin4V.png TF EIM Lab9 P2 Vin7V.png TF EIM Lab9 P2 Vin9V.png


  1. Explain your results in parts 1 & 2 in terms of the diode turn-on voltage. (20 pnts)