Is there any simple way to double amplitude of single square pulse?

Discussion in 'General Electronics Chat' started by Dong-gyu Jang, Aug 31, 2015.

  1. Dong-gyu Jang

    Thread Starter Member

    Jun 26, 2015
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    Hello.

    I'm trying to build the circuit which increases amplitude of single square pulse (5 V in amplitude and 10 us in pulse duration and ~10 ns in rising and falling time.) to 10 V or more.

    As the amplified signal is for triggering some experimental instrument, I guess low output impedance of amplifying circuit is preferred to minimize signal distortion. I've considered OP-AMP for this purpose but It requires negative supply voltage so I got a difficulty to how to achieve this.

    I guess there maybe some ICs for my original purpose. If you know, could you please recommend the products or any simple way for pulse amplitude doubling?
     
  2. pwdixon

    Member

    Oct 11, 2012
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    You could use two bipolar transistor stages in series.
     
  3. Dong-gyu Jang

    Thread Starter Member

    Jun 26, 2015
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    Do you mean Darlington transistor? What does it make difference than single tansistor? I thought it mainly has advantage of high gain and I don't need such a high gain. And besides does it has low output impedance?
     
  4. ScottWang

    Moderator

    Aug 23, 2012
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    Two stages in series with Fig-02, the +V in first stage is +5V and the second stage is 10V.
    According to your frequency to adjust the values of Rb an Rc.

    [​IMG]
     
    Cjuried likes this.
  5. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    There are lots of ways to do this. What is your "load" on the next input stage of the instrument you are driving. Is it MOSFET or BJT or other. Do you have model numbers?

    If BJT, is there a capacitor and/or resistor between input and base? Is there an emitter resistor? What values?

    You listed rise times and fall times but, is propagation delay a concern?
     
  6. Dong-gyu Jang

    Thread Starter Member

    Jun 26, 2015
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    Well...You're talking about internal structure of the instrument and That's I really don't know.

    What I only know is 1) It recommended above 10 V triggering signal to start its operation and 2) Its input impedance is 470 Ohm as minimum.

    I can upload the document of the instrument but I'm not sure it contains a lots of info you want.

    It is actually triggering box to Thyratron for gas discharge.
     
  7. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    In that case, lets just talk about propagation delay. Are you starting your clock when the pulse to this new driver starts or when it triggers your instrument? A few nSec to 10s of nSec will be needed in most cases from input signal to output signal - exact will depend on needed current, transistors and circuit configuration.

    Will a delay screw up anything for you?
     
  8. Dong-gyu Jang

    Thread Starter Member

    Jun 26, 2015
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    As long as propagation delay is fixed, It doesn't matter at all. I can always compensates this with our commercial delay generator, which gives original single square pulse with only 5 V.
     
  9. MikeML

    AAC Fanatic!

    Oct 2, 2009
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    A pulse transformer with a two-to-one turns ratio?
     
  10. atferrari

    AAC Fanatic!

    Jan 6, 2004
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    I could be dead wrong but at two places that .pdf mentions a maximum pulse of 30V. Not used a thyratron in the last 60 years. ??
     
  11. pwdixon

    Member

    Oct 11, 2012
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    But what's interesting is that the minimum trigger voltage is 5V which means you shouldn't need to amplify the input at all.
     
  12. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    But if the minimum trigger is 5V then that would leave no margin if the OP's pulse gen can put out only 5v.
     
  13. atferrari

    AAC Fanatic!

    Jan 6, 2004
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    Yes, but going up to 100V, isn't that too much of a precaution?

    Honestly, I suspect I am reading something wrong in the manual. Just in case I will stop here.
     
  14. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    :confused: As I read it the input pulse must be in the 5V-30V range. One of Scott Wang's circuits (post #4) should do the trick if components are chosen to meet the trigger current necessary (the driver input has a minimum impedance of 470Ω).
     
  15. alfacliff

    Well-Known Member

    Dec 13, 2013
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    use a 1:2 pulse transfrormer.
     
  16. pwdixon

    Member

    Oct 11, 2012
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    see post #9
     
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