1 / 14

Signals and Network Analysis

Signals and Network Analysis. Target group. 3rd year ECED Students. 2 Lecture Hours 3 Tutorial Hours. Contact hours:. School of Computing and Electrical Engineering. Eeng-3121. Signals and Network Analysis. Chapter 5. Active Networks. Active Networks. Active elements.

dakota
Download Presentation

Signals and Network Analysis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Signals and Network Analysis Target group 3rd year ECED Students 2 Lecture Hours 3 Tutorial Hours Contact hours: School of Computing and Electrical Engineering Eeng-3121

  2. Signals and Network Analysis Chapter 5 Active Networks

  3. Active Networks Active elements Require external power supply e.g. transistors and operational amplifiers Active Networks Electrical network with at least one active element Active Network Elements • Elements that make up active networks • Can be classified as basic and secondary elements Basic elements • Elementary passive elements (resistors, capacitors and inductors) and active elements such as operational amplifiers.

  4. Active Networks Secondary elements • Made up of basic elements. • Used as building blocks for complex network and to simulate functions that can not be realized using basic elements • Negative impedance converter (NIC)

  5. Active Networks • Generalized impedance converter (GIC) ZIN = q(s)Zout For example, if Z2 = R2, Z3 = R3, Z4 = R4 (resistors), Z5 = 1/Cs (Capacitor) and the termination load Z6 = R6 Simulation of an inductor

  6. Active Networks • Frequency dependant negative resistance (FDNR)

  7. Active Networks • Operational Amplifiers • high voltage gain, DC amplifier • high input impedance • low output impedance • Positive input at the non-inverting input produces positive output; positive input at the inverting input produces negative output.

  8. RS + RL vout - Active Networks Ideal op-amp • Place a source and a load on the model • Infinite internal resistance Rin (so vin=vs). • Zero output resistance Rout (so vout=Avvin). • "A" very large • iin=0; no current flow into op-amp

  9. Active Networks Many Applications • Amplifiers • Adders and subtractors • Integrators and differentiators • Clock generators • Active Filters • Digital-to-analog converters

  10. Active Networks • Op-Amp circuits Inverting feedback circuits When the two impedance elements are resistors, then the circuit becomes inverting amplifier.

  11. Active Networks • Op-Amp circuits Non-inverting feedback circuits When the two impedance elements are resistors, then the circuit becomes non-inverting amplifier.

  12. Active Networks • Op-Amp circuits Voltage follower Useful interface between different circuits Avoids loading effect • Buffer characteristics • voltage gain = 1 • input impedance=∞ • output impedance=0

  13. Active Networks • Realization of Active network realized using operational amplifiers and RC elements. Inductors are not common in active networks because of their large size Transfer functions of simple feedback circuits have orders not more than 2. In most applications such as filters and control systems, higher order transfer functions are required. Break the given transfer function in to product of smaller 1st and 2nd ordered transfer functions and realize as cascaded interconnections of sub networks

  14. Active Networks • Example Realize the following transfer function using opamps and RC elements.

More Related