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I've made a circuit:

enter image description here

Here is link to this circuit emulator: amplifier circuit The first scope is a 10 kHz input generator and the second scope is circuit output. Which element should be changed to get the output pulses wider?

Edit:

I found the circuit I was looking for: enter image description here

How to make simulation of this circuit? Is it possible to increase output \$e_{0}\$ to hundred of millivolts?

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    \$\begingroup\$ The beauty if using a simulator is that you can just try and see what happens. So which component(s) do you think will make the pulses wider? Now change their value (not 10 kohm => 11 kohm but a factor 2 so 10 kohm => 20 kohm) and see what happens. \$\endgroup\$ Jan 9, 2022 at 21:31
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    \$\begingroup\$ Your question needs a lot of work. No voltage scale, no time scale, and the pulses are so narrow that they convey almost zero information. AND - why do you think this circuit works at all? Please explain why you think you need a 10 meg resistor in a feedback loop, and why neither end of the signal generator is grounded. \$\endgroup\$
    – AnalogKid
    Jan 9, 2022 at 21:53
  • \$\begingroup\$ 10kΩ to 20kΩ only lowers the amplitude. \$\endgroup\$ Jan 9, 2022 at 21:53
  • \$\begingroup\$ Could you clean up the schematic so the elements are closer together? That would make it a lot easier to understand. Also, put positive supply voltages toward the top of the sheet and negative supply voltages toward the bottom. Change the horizontal scale of the scopes to see the pulse better. \$\endgroup\$ Jan 9, 2022 at 21:55

2 Answers 2

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With experience on how to do a layout better, I do this.

  1. Use correct polarity for supplies +ve on top, not bottom
  2. Use > Draw> Output Label > node then define label, resize, ^D to duplicate , place
  3. delete very long skinny lines to a concise layout
  4. use Ctrl+ Mouse to stretch endpoint or accurate end point and stretch
  5. use Draw > drag columns or rows to rescale about cursor in Y or X axis (carefully, not all items move)
  6. Use thumbwheel to scroll values hovered over part or alt-click edit, same with plot time scales.
  7. adjust sampling rate for 1k points, Options>other options> timescale then thumbwheel to slow down plots and simulation slider.
  8. Over plot, alt-click > Properties> and click more Show Info boxes
  9. oh I forgot turn off nuisance current dots. > Options >show current (not)

If you want to undo ^Z, redo ^Y and many other hot-keys to save time.

The design needs specs for input V min max, PW and output specs then choose design as LPW and pulse stretch with Vdc offset or AC couple..... but that's another answer after you define ALL SPECS. enter image description here

Choose defaults you like then Book mark or export , save. Tinyurl's only work in comments.

You can even undock plots and resize with Ctrl=^ key and mouse click (^+click) and drag

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  • \$\begingroup\$ Plot zooms only work with mouse when Docked, otherwise schematic zooms. I think you want something like this tinyurl.com/y3med6dv or this , tinyurl.com/y32kwhaz but remember this , Op Amps make lousy high-speed comparators. ( not always rail to rail and slow slew rate) \$\endgroup\$ Jan 9, 2022 at 23:07
  • \$\begingroup\$ I precised my question and updated the post. \$\endgroup\$ Jan 12, 2022 at 19:26
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Your question needs a lot of work. No voltage scale, no time scale, and the pulses are so narrow that they convey almost zero information. AND - why do you think this circuit works at all? Please explain why you think you need a 10 meg resistor in a feedback loop, and why neither end of the signal generator is grounded.

Both of your opamp circuits are a form of a linear amplifier. As such, there is no one element that can be changed to turn it into a pulse form circuit. You need a different circuit.

If you want the leading edge of the input signal to initiate an output pulse of some independent width, that circuit is called a monostable multivibrator. This can be done with an opamp, a comparator, two digital logic gates, or a digital logic part designed specifically for this. A search for monostable schematic or monostable circuit will bring up hundreds (thousands?) of examples.

Is this school work, or work-related?

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