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Ohm's Law

Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points.

Learning goals:
  • Starting OrCAD Capture
  • Starting a new project
  • Making a schematic compatible with PSpice
  • Performing a DC sweep
  • Component values and prefixes
  • Make the following schematic in OrCAD Capture
  • Run a simulation to find out how much current run through the resistor
  • Find out how many amps run throught the resistor for 1V to 10V
  • Do you get the same results as you did in your own calculation?

Voltage dividers

A voltage divider is a passive linear circuit that produces an output voltage (Vout) that is a fraction of its input voltage (Vin). Voltage division is the result of distributing the input voltage among the components of the divider. A simple example of a voltage divider is two resistors connected in series, with the input voltage applied across the resister pair and the output voltage emerging from the connection between them.

Learning goals:
  • Autoconnect
  • Time Domain (Transient) simulation
  • Toggle Cursor function
  • Bias points (V, I, W)
  • Calculate the voltages and how much current goes through the resistors for the four schematics above
  • Use OrCAD Capture to create schematic drawings and simulations
  • Do you have the same results as the ones PSpice gives?

Kirchoff's Voltage Law

Kirchoff's Voltage Law simply states that the directed sum of the electrical potential differences (voltage) around any closed network equals zero.

Learning goals:
  • Voltage difference marker
  • Figure out if the sum of the voltages above equals zero
  • Make the scheamtic in OrCAD Capture and find out if Kirchoffs Voltage Low applies here


The superposition theorem for electrical circuits states that for a linear system the response (voltage or current) in any branch of a bilateral linear circuit having more than one independent source equals the algebraic sum of the responses caused by each independent source acting alone, where all the other independent sources are replaced by their internal impedances.

Learning goals:
  • Using a DC current source
  • Calculate the voltage across resistor R14
  • Use PSpice to check whether your calculation matches the one that PSpice gives

The Capacitor's V-I phase difference

In the schematic below you see a capacitor with a sine wave generator. When an AC signal comes through a capacitor, a phase difference between the voltage and current appears

Learning goals:
  • Independent sources
  • Add Y axis
  • How do the voltage graph and the current graph look? Is there a phase difference?
  • Use PSpice to see if what you learned in theory is the same results as PSpice shows

Charging and discharging a capacitor

In the image below you see a DC voltage source connected with a resistor and a capacitor. There are two switches as well. One is always open, and the other is always closed. Therefore we only have two cases: the capacitor can either be charged or discharged.

Learning goals:
  • Modeling applications (Customized components)
  • How does the capacitors charging and discharging look like?
  • Spend 50 seconds on charging the capacitor and the 50 seconds on discharging it
  • Use PSpice to see if what you learned in theory matches the results you get from PSpice

RC Filter

A resistor-capacitor circuit (RC circuit), or RC filter or RC network, is an lectric circuit composed of resistors and capacitors driven by a voltage or current source. A first-order RC circuit is composed of one resistor and one capacitor and is the simplest type of RC circuits. RC circuits can be used to filter a signal by blocking certain frequencies and passing others. The two most common RC filters are the high-pass filters and low-pass filters.

Learning goals:
  • AC sweep
  • Pspice advanced markers (dB, phase)
  • Bode plot
  • What is the cut-off frequency?
  • How does the frequency response look like?
  • Use PSpice to see if your calculations are identical to the results from the simulation

RLC Filter

A RLC circuit is an electrical circuit consisting of a resistor (R), and inductor (L) and a capacitor (C), connected in series or in parallel. The name of the circuit is derived from the letters used to denote the constituent components of the circuit, where the sequence of the components may vary from RLC. A RLC circiut can be used as a band-pass filter, band-stop filter, low-pass filter or a high-pass filter. The RLC filter is described as a second-order circuit, meaning that any voltage or current in the circuit can be described by a second-order differential equation in circuit analysis.

Learning goals:
  • Independent Sources (Pulse generator)
  • What does the frequency response look like in each of the two schematics?
  • What does the phase look like for each schematic?
  • What does a step function look like in each of the schmatics?
  • Use PSpice to check if your calculations are similar to the calculations from PSpice

Operational amplifiers

An operational amplifier (often called op-amp or opamp) is a DC-coupled high-gain electronic voltage amplifier with a differential input and, usually, a single-ended output. In this configuration, and op-amp produces an output potential (relative to circuit ground) that is typically hundreds of thousands times larger than the potential difference between its input terminals.

Learning goals:
  • Search a PSpice component
  • Double power supply
  • How much does the circuit amplify, and in what bandwidth?
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