Op amp

From OpenCircuits
Revision as of 22:28, 1 February 2008 by (Talk)

Jump to: navigation, search

ring stunning precipitation maps of usa ron routh japanese import games novartis washington credit union seattle half moon bay real estate lonley by akon hybrid golf travel bag woodstock georgia real estate coflex seeve sexy guys dicks kinski natasha nude emily 18 kendra topless wilkinson arizona game and fish kay parker free picture showgirls trailers jenna jameson free videos teenage birthday games internet scams bus stop down electric light orchestra institute of engineer india commercial janitorial supplies florida jupiter map double penetration jpg ahorro de prestamos software y woohoo vitrectomy solutions ladybug tea set how to shave pubic hair vorizon 0 apr cinderellas castle electrode system journal.com state wisconsin free dirty taboo story precedently armadillo sales teachers rubber stamps aim celebrity name screen motorola v3 razr allegheny power company elite screen review embroidered personalized pants house record preserving fresh flowers university of evansville molded wood dash in job non organiza profit automotive battery charger spinning chrome rims lung cancer in non smokers eye gel annealed steel wire greek beach india agriculture statistics hoodia for weight loss foam flooring young boys in speedos galleries sexy high heel yahoo cam salt lake county utah facts en kompas language language nl voice chat immobilier nord aveyron toyota used auto part high school bikini girls my life printable baby shower invitation audio video equipment cases service arizona norton live update download gigantic natural breast christiancafe.com member kyocera ringtones alpha kappa alpha and delta sigma theta american national anthem irving penn van briggle pottery horse movie taux interet legal bass bass business development jossey jossey management organization reader reader series raglan hall london www.cartoonnetwork.com parquet floor repair collecting baseball autographs type of lip piercing business opportunity seeker absolutely story of a girl nine day playing black jack for fun alexander romanov jungle fever used belly dance costume for sale kid to kid plano tx aerosmith what it takes tab 1.4lite email extractor rini penn station newark nj job search new mexico justina reflection bay lake las vegas mathew mcconaughey 199 computer thai lemongrass chicken recipe tumescent liposculpture perform oral sex who is hotter starfire or blackfire california state franchise tax board scaletronix nicola ciccone chansons silicone case and treo 650 big booty bubble msa safety equipment super saiyan 5 goku dragonball af koenigsegg 300 can degree law more than things neuron accountancy in job leeds handicapped tools female impersonator la laker tickets motor building tools thrustmapper download yesterday tractor co what does this mean about me horseshoe art persistent fever in children moorpark california www.health.com celestron telescopes 18 year old wild girls network monitoring software free anime nude gallery green dayholiday pizzahut rio salado college online alumna chapter memphis houston jobs mobiles wallpaper thin hansgrohe glider ride wilkinson personalized custom golf balls sexy beachwear An op amp ("operational amplifier") is a very high gain voltage amplifier ( the normal type ) usually with differential input, and response from DC to 1 Meg Hz or more. Mostly used with negative feedback so that the characteristics of the circuit is determined by the mostly passive components in the feedback circuit. One of the most useful analog components in the frequency range where they work.

Great for amplifying weak signals from sensors to a more useful level. Also used in filters, integrators, etc.


Quick Summary

  • Many sensors need an amplifier to "buffer" their output signal. Often a single op amp is adequate. For very weak signals, you may want a "difference amplifier" or "instrumentation amplifier".
  • All ADCs need an anti-aliasing filter on their input. Often a single op amp, 2 caps and 4 resistors is adequate.
  • If you want to hear a signal, use a LM386N-3 (under $1) to amplify it enough to drive a small speaker.
  • If you want to drive heavy loads (big speakers, big antennas, electric motors, etc.), too heavy for typical op amps to drive, use op amps to amplify the signal to the desired voltage, followed by power transistors to drive the load [Veselinovic].


Suppliers such as Jameco, Digikey, and Newark each have pages and pages of fine print listing hundreds of op-amps, from "low-cost" quad op amps for under $0.40 each to "hi speed precision" op amps for well over $10 each. That doesn't include more complex devices (such as voltage regulators and RS-485 transcievers ) that combine op amps and other components on a single IC. Each one of those op amps has a data sheet several pages long packed with lots of details, which you can freely download from the manufacturer's web site.

"But in reality, there are only two important specifications that you should initially consider when selecting an op amp for your active, low-pass filter. ... Gain Bandwidth Product and Slew Rate." [Baker 2003]

designing the circuit around the op amp

CookBook of Circuits ( links )

OpAmp Links

selecting the appropriate op amp out of the hundreds (thousands?) available

Personal tools