Half-wave Rectifier
Fig. 1 Schematic of the half-wave rectifer and the
D1N4002 model pop-up window
Analysis:
1. Calculate the maximum output voltage for a half-wave rectifier using the piecewise
model for a diode. Assume that the diode used in the rectifier is D1N4002, which has a
Von = 0.3905 V and Rs = 33.89 m according to the model in PSpice (shown in Fig. 1).
2. Design a circuit in which a capacitor is in parallel with R1 to obtain a ripple voltage, Vr,
of 0.5 V. Chose a resistor valve for R1 that is relatively large (> 500 ) from the list of
5% tolerance resistors and a capacitor whose value can be measured using the digital
multimeter (C < 20 F).
Modeling:
3. Build the half-wave rectifier circuit in PSpice without the capacitor in the circuit.
a. Select VSIN for your input voltage supply.
i. Save the following attributes:
1. VOFF = 0V
2. VAMPL = 5V
3. FREQ = 1k
b. Select diode D1N4002 from the parts list.
4. Using the DC Sweep and Transient analysis, simulate the output voltage of a half-wave
rectifier.
Note that VSIN can be used for a source for DC and AC Sweeps as well as the Transient
analysis.
a. Set the start valve to -5 V and the end valve to +5 V for the DC Sweep analysis.
i. The plot obtained is called the voltage transfer function or voltage transfer
characteristics.
b. Set the final time to 3 ms for the Transient analysis.
c. Print the graphs from each of the simulations.
d. Using the cursors, determine the magnitude of the maximum and minimum
voltages across R1. Why is the minimum voltage negative?
5. Rebuild a half-wave rectifier circuit with the capacitor in the circuit. Rerun the Transient
analysis after selecting a final time such that the circuit operation has reached steady
state.
a. Print the graph.
b. Using the cursors, determine the magnitude of the maximum voltage across R1
and the ripple voltage.
Measurement:
6. Build the half-wave rectifier circuit using the value of R1 that you selected in Step 2, but
do not include the capacitor.
a. Measure the maximum and minimum voltages across R1. Compare the measured
results with the expected and simulated values.
7. Rebuild the circuit that you designed in Step 2 using a combination of at most two
capacitors that are available in the parts kit.
a. Measure the maximum voltage across R1 and the ripple voltage.
b. Determine the percent errors from the expected values.
8. Determine the actual values for R1 and C using the digital multimeter and the value for
Von using a curve tracer.
a. Using these values, recalculate the ripple voltage.
b. Determine your percent error of your measured value compared to the revised
expected value calculated using the measured values for R1, C, and Von.
Note: One method to calculate Von is to extrapolate the linear section of the forward I-V
characteristic to find the intersection of the linear portion of the I-V with the x-axis. The voltage
at this intersection is Von.