PC201: Physics Laboratory I

Project List

Project Group 1: Filter Circuits

The following group of circuits are designed to have an impedance with certain characteristics (magnitude and/or phase) at a particular frequency or over a range of frequencies. Some of these filter circuits are part of an oscillator circuit. An oscillator circuit is basically a filter circuit together with an amplifier. It works by amplifying noise and using feedback. Since noise will be present in any circuit, then noise at the input of an amplifier will produce a larger output noise signal. If this noise signal is passed through a filter circuit, and then fed back into the input of the amplifier, to be amplified again, then the signal will get bigger if the input and output signals are in phase. So if the filter circuit only produces an output which is in phase at a single frequency, then there will be only one frequency for which the amplification will reinforce the original signal. This is the frequency at which the circuit will oscillate.

You will have to first determine what is required by this particular circuit.

1. Twin T Filter
   
   This circuit, which is composed of resistors and capacitors, rejects a very narrow band of frequencies.
2. RC p Filter
   
   This circuit, which is composed of a resistor and capacitors, is used to remove AC ripple from a dc source.
3. LC p Filter
   
   This circuit which is composed of an inductor and capacitors, is used to remove AC ripple from a dc source.
4. Series Resonant Band-reject Filter
   
   Use a series RLC circuit to reject a selectable band of frequencies.
5. Series Resonant Band-pass Filter
   
   Use a series RLC circuit to pass a selectable band of frequencies.
6. Parallel Resonant Band-reject Filter
   
   Use a parallel RLC circuit to reject a selectable band of frequencies.
7. Parallel Resonant Band-pass Filter
   
   Use a parallel RLC circuit to pass a selectable band of frequencies.
8. RC Phase shift network
   
   This circuit, which is composed of 3 resistors and 3 capacitors, produces a 180° phase shift at a particular frequency.
9. Filter portion of a Wein-Bridge oscillator
   
   This circuit, which is composed of resistors and capacitors, produces a 360° phase shift at a particular frequency.
10. Filter portion of a Colpitts oscillator
    
    This circuit, which is composed of resistors and capacitors, produces a 180° phase shift at a particular frequency.
11. Filter portion of a Hartley oscillator
    
    This circuit, which is composed of resistors and capacitors, produces a 180° phase shift at a particular frequency.

Project Group 2: Modeling

Often a complex circuit can be represented by a combination of simpler components. In these circuits, you will investigate these models.

12. TTL modeling-simulator model
    
    Compare the performance of the analog simulator model of a TTL gate with the actual gate for voltage, current, and timing parameters.
13. TTL modeling-transistor model
    
    Model a TTL gate with discrete components and compare the performance of the model with the actual circuit made from those components for voltage, current, and timing parameters.
14. CMOS modeling-simulator model
    
    Compare the performance of the analog simulator model of a CMOS gate with the actual gate for voltage, current, and timing parameters.
15. CMOS modeling-transistor model
    
    Model a CMOS gate with discrete components and compare the performance of the model with the actual circuit made from those components for voltage, current, and timing parameters.
16. Crystal modeling
    
    A piezoelectric crystal is a device which is used to produce very precise resonant frequencies; it can be modelled by RLC components. The project is to compare the model to an actual device.

Project Group 3: Analog circuits

These are a collection of various active circuits with operational amplifiers, for various purposes.

17. Oscillator of sine waves of a Wein-Bridge using Op-Amp

            This circuit, which is composed of op-amp and Wein-Bridge, produces an oscillator.

18.  Band-pass filter using Op-Amp and RC circuit

           This circuit, which is composed of op-amp and RC circuit, produces a band-pass filter.

19.  AC amplifier using multi-stage Op-Amp.

          This circuit, which is composed of two op-amp, produces an amplifier for AC signals.

20.  Generation and transformation of pulse waves using Op-Amp.

         This circuit, which is composed of op-amp, resistors, capacitor and diodes, produces rectangular waves and then transfers to triangular waves.

21.  AC/DC linear detector using Op-Amp.

         This circuit, which is composed of op-amp and filter, transfers AC signals into DC voltage.

22.  RC amplifier with 5 band-tone control

         This circuit, which is composed of op-amp and 5 band-pass filters, produces a tone control for music signals.