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    Increasing the output current of a Waveform signal generator.

    Hello guys,

    I am using a waveform signal generator to generate a sinus test signal and test a signal conditioning circuit:

    https://www.aimtti.com/product-categ...-tga1240series

    But the input impedance is very low and the amplitude of the output sinus signal is very low too. Have a look to the picture:

    Click image for larger version. 

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    I would like to introduce a simple previus stage which is able to amplify the input signal to have something like this:

    Click image for larger version. 

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    Any idea?

    Thanks in advance

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    Re: Increasing the output current of a Waveform signal generator.

    You don't need to amplify the signal.A simple Buffer ( even a single transistor ) or A Voltage Follower with a OpAmp will serve you..



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    Re: Increasing the output current of a Waveform signal generator.

    Hi,

    most OPAMPs are not able to drive 2A of ouptut current.

    Klaus
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    Re: Increasing the output current of a Waveform signal generator.

    Almost useless post without mentioning frequency range and performance requirements (e.g. THD, offset). Generally, as correctly annotated in your block diagram, you are looking for an amplifier. Detail specification depends…


    most OPAMPs are not able to drive 2A of ouptut current.
    Yes, but some do. I have a TDA20xx as +/-10 V power buffer for similar applications. Devices with MHz bandwidth are available as well.



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    Re: Increasing the output current of a Waveform signal generator.

    Hi it is a quick test with minimum performance. I just need to give more current to the input sinus signal using a pre-stage circuit to have an output signal with the same amplitude but stronger. I have thinking to use a current buffer opamp, but it is not working with bipolar signals...

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    Quote Originally Posted by FvM View Post
    Almost useless post without mentioning frequency range and performance requirements (e.g. THD, offset). Generally, as correctly annotated in your block diagram, you are looking for an amplifier. Detail specification depends...



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  6. #6
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    Re: Increasing the output current of a Waveform signal generator.

    http://www.ti.com/amplifier-circuit/...3typ=200;10000

    There are few OpAmps which are able to drive upto 10A and Dual Supply Features.
    In fact, the circuit that you're looking for is typical Power Output Stage of an B-Class Audio Amplifier but the frequency here is a serious issue.
    So you drive the circuit with a bipolar voltage swing and a current source ( NPN and PNP conducts at each cycle) supplies desired current to the load.



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