Simulation of electrical circuitsLaajuus (3 ECTS)

Objective

To learn to use one modern electrical simulation program and to understand its restrictions
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The ability to see in advance by simulation the functional errors in the possibly soon to be build electronic device before the manufacturing of the printed circuit board and mounting of the components.

Content

The basics for example for OrCad-simulation program.
Project works:
1) Operational amplifier with a frequency dependent amplification.
- The reasons for the shortcomings in the simulated frequency response are investigated: What is caused by the limited capabilities of the components, do better components exist.
- It is looked from the frequency response for any tendencies of the circuit to oscillate.
- Circuit’s tendency to oscillate is examined from the step response.
- The tendencies to oscillate are corrected away.

2) Comparing the abilities of one and two transistor amplifiers
- The amplifiers of one (CE/CC/CB) and two transistors (CE-CB or Cascode, CC-CB and CC-CE) are classified.
- As an example, a CE and Cascode amplifier are simulated side by side.
- The rise and falling time are learned to measure from the simulation results both with cursors and automatically.
- The stalling time is learned to measure.
- The distortion in the signal is learned to measure.
- The noise in the signal is measured.
- The frequency response is simulated in the same picture with different temperature values.
- The frequency response is simulated in the same picture with many different values of a component.

3) Making one’s own components
- As block from old components.
- The electrical parameters in a diode are modified.
- The drawing symbol of a diode is modified.
- Many simulation curves with different values of a parameter in a transistor are drawn in the same picture.
- A completely new drawing symbol is made for a transistor and connected to the existing electrical model.

4) Designing of a circuit board
- A simple circuit is drawn. E.g. two resistors and a connector.
- Circuit is normally simulated.
- The necessary new parameters for making the circuit board are defined for the components (footprint, PSpice-only…).
- The “netlist” is made from the components, whereupon the execution jumps automatically to the PCB Editor.
- The sizes and the basic properties of the circuit board are defined.
- The components are read from the netlist onto the circuit board.
- The wiring is done (automatically with a push of a button or manually).
- In additional instructions there are explained, how to prepare the circuit board for the carving machine.

Qualifications

Basics in Digital Electronics

Assessment criteria, satisfactory (1)

1. The student understands the significance of circuit simulation in modern electronics product development and masters the basics of one circuit simulation software.

Assessment criteria, good (3)

1. The student can use the circuit simulation software fluently to simulate given circuits.

Assessment criteria, excellent (5)

1. The student can apply the circuit simulation software to design new circuits.