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Trouble using a 741 op-amp

  1. Feb 8, 2010 #1
    i am new to most of this so my confusion is basic. here is my problem.

    I am using a 555 timer to create a squarewave frequency of between 20-80khz

    BUT the output is 1vpp. i am using this to drive a motor and need to up the voltage and current. i know what i need to use i just cant for the life of me figure out how to set up the op-amp to get say 5v's or so.

    after the opamp i plan to use a transistor in an emitter follower configuration to drive the motor
  2. jcsd
  3. Feb 8, 2010 #2


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    Maybe I'm reading it wrong, but are you calling a 555 an opamp?

    It isn't. A 555 is a timer chip and it produces an output on pin 3 of something close to its supply voltage. if you had a 5 volt supply, you should be getting pulses varying from almost zero volts to almost 4.5 volts positive.

    See this site for a nice calculator, but also a diagram of the pinout of the 555.
    Last edited by a moderator: Apr 24, 2017
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