Lab 3: Circuit Reduction and Two-Terminal Characteristics
I. Resistor Voltage-Current Characteristics (20 pts)
Pre-lab:
i.
Sketch below a schematic of the circuit you designed to implement the
800 resistance. (2 pts)
ii.
Sketch below a schematic of the circuit you designed to implement the
25 resistance. (2 pts)
Lab Procedures:
1.
i.
List below the measured values of the individual resistors in the
network you designed to create an equivalent 800 resistance.
Provide the measured resistance of your resistance network. Indicate
whether the design requirements were met. (5 pts)
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©2015, Tim Hanshaw
Lab 3: Circuit Reduction and Two-Terminal Characteristics
ii.
List below the measured values of the individual resistors in the
network you designed to create an equivalent 25 resistance.
Provide the measured resistance of your resistance network. Indicate
whether the design requirements were met. (5 pts)
2. DEMO: Have a teaching assistant initial this sheet, indicating that they have observed
your circuits’ operation. (6 pts)
II. Non-Ideal Power Sources (30 pts)
Pre-lab:
a) What is the value of Vout for an ideal source? (2 pts)
b) What is the expression for Vout for a source with internal resistance RS?
(2 pts)
Lab Procedures:
1. Measured resistance R: (1 pts)
2. Value of VS with source terminals open-circuited: (2 pts)
3. Value of Vout with resistance R connected to circuit: (2 pts)
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©2015, Tim Hanshaw
Lab 3: Circuit Reduction and Two-Terminal Characteristics
4. Estimated internal resistance (5 pts)
5. DEMO: Have a teaching assistant initial this sheet, indicating that they have
observed your circuit’s operation. (5 pts)
6. Estimated source resistance with 20 load resistance. Comment on
agreement between the two source resistance estimates. (10 pts)
III. Non-Ideal Voltage Measurement (25 pts)
Pre-lab:
a) What is the value of Vout for an ideal voltmeter? (2 pts)
b) What is the expression for Vout for a source with internal resistance RM?
(2 pts)
Lab Procedures:
1. Voltage Vout measured with DMM: (2 pts)
2. Estimated DMM voltmeter resistance: (6 pts)
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©2015, Tim Hanshaw
Lab 3: Circuit Reduction and Two-Terminal Characteristics
3. DEMO: Have a teaching assistant initial this sheet, indicating that they have
observed your circuit’s operation. (5 pts)
4. Voltage Vout measured with Analog Discovery voltmeter and estimated
Analog Discovery voltmeter resistance. (8 pts)
IV. Voltage-Current Characteristics of Two-Terminal Networks (25 pts)
Pre-lab:
a) Functional voltage-current relationship and plot. (2 pts)
b) Open circuit voltage and equivalent resistance of circuit: (2 pts)
Lab Procedures:
1. Measured resistance values in circuit: (1 pt)
2. Table of voltage vs. current data and slope and y-intercept of data: (5 pts)
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©2015, Tim Hanshaw
Lab 3: Circuit Reduction and Two-Terminal Characteristics
3. Measured open-circuit voltage (3 pts)
4. Measured equivalent resistance (2 pts)
Post-lab exercises:
1. Summarize differences between measured and expected slope of voltagecurrent relationship. Include measured and expected values and comment
on results. (5 pts)
2. Summarize differences between measured and expected y-intercept of
voltage-current relationship. Include measured and expected values and
comment on results. (5 pts)
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©2015, Tim Hanshaw