1 / 21

Building Circuits with Op-Amps: Practical Medical Device Applications

Learn the fundamentals of using op-amps in medical instrument circuit design and troubleshooting. Understand op-amp characteristics, practical applications, circuit gain, feedback, and troubleshooting techniques in a lab setting.

dung
Télécharger la présentation

Building Circuits with Op-Amps: Practical Medical Device Applications

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. Building Circuits 415-3

  2. General Medical Instrument (Webster) 415-3

  3. General medical device gain sensor filter v gain Further processing, display, etc. filter ADC 415-3

  4. Breadboards 415-3

  5. Breadboards 415-3

  6. Breadboards 415-3

  7. Breadboards 415-3

  8. Breadboards 415-3

  9. Breadboards 415-3

  10. Op amps will be used in most labs. • d – differential • A – voltage gain • Z – impedance (usually resistive) 415-3

  11. Ideal op amps • ZD →∞ Ω • Zout →0 Ω • AD →∞ V/V • Therefore, 415-3

  12. We must use negative feedback to achieve non-saturated output. • The output is connected to the inverting input of the op amp. • The circuit gain, G, is much reduced from AD. • The voltages at the two inputs are nearly equal. • Use above and i+,-=0A to solve op amp circuits. • Voltage follower • Inverting amplifier 415-3

  13. Answers? • Voltage follower • G=? • Inverting amplifier • G=? 415-3

  14. Answers? • Voltage follower • G=1V/V • Inverting amplifier • G=-10k/680=-14.7V/V 415-3

  15. In lab we don’t have ideal op amps. • Manufacturer’s produce spec sheets that detail actual device characteristics. • The first page has the device name, a general description, and call-outs of important features. 415-3

  16. “Connection Diagrams” tell how to hook up the op amp. • NC – no connection • V+, V- are DC power connections • Dual-in-Line package (or DIP) fits in breadboard • Most op amps have similar pinouts, but there are differences! 415-3

  17. Compare to a real chip Note: This is the positive power supply voltage, not the non-inverting input (which is labeled v+ in every textbook). 415-3

  18. Op amps on your breadboard Negative power supply Ground Positive power supply 415-3

  19. Op amps come have maximum ratings • Check max. supply and input voltages • Other Max ratings will probably not be important for this course. 415-3

  20. Much of the info is in tables or charts • Each characteristic may be described by a minimum, typical, or maximum value • The numbers apply only under conditions listed. • Check Units! • There are more characteristics listed than we will learn about. 415-3

  21. Troubleshooting in lab • Know what to expect • Given input, what should output be? • Given resistor tolerances and op amp specs, is output reasonable? • Check the power supplies • Are they on? • Do the voltages indicated on the DC power supply actually appear at the op amp’s pins? • Overload lights? • Is the op amp operating in its linear region? • Is the output saturating? • Is the Gain-bandwidth product limiting the output? 415-3

More Related