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I want to shift the red square wave to let its position be the same as the blue square wave,is there a schematic can solve this problem?

I know the shift register may solve this problem,however,it needs clock,but in my ic application,there is no clock to support me outside.

The blue wave position is what i wanted,off chip.The red wave is to replace the the blue wave from the internal circuit,and the red wave is the output of adjustable delay schematic,the information for it is from here :Peak detection comparator simulation problem.(Process and no VSS version) and What is \$V_{ADJ}^{+}\$ and \$V_{ADJ}^{-}\$ for this adjustable delay schematic?

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    \$\begingroup\$ Unless the two waveforms are manually generated -- that is, no temporal restriction exists for when to generate them -- there is no way to advance in time a pulse. You can only delay the blue pulse to align it with the red one. \$\endgroup\$
    – a concerned citizen
    Commented May 6, 2018 at 9:04
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    \$\begingroup\$ You are going back in time. Unless you know what triggered the pulse you can't do that. (Flux capacitors are still difficult to get) \$\endgroup\$
    – Oldfart
    Commented May 6, 2018 at 9:04
  • \$\begingroup\$ @aconcernedcitizen can you tell me which circuit can delay the blue pulse to align it with the red one?i hope there is no clock in that circuit \$\endgroup\$
    – XM551
    Commented May 6, 2018 at 9:15
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    \$\begingroup\$ Are your signals digital signals, i.e. are you asking your question in the context of digital processing/electronics? As other pointed out, you can't go back in time (unless you perform off-line processing, i.e. not real time). So you need a delay, which is done very differently in the digital and the analog domains. \$\endgroup\$
    – LorenzoDonati4Ukraine-OnStrike
    Commented May 6, 2018 at 10:19
  • \$\begingroup\$ You need to provide a lot more context about what you are trying to do, and where these pulses come from. Otherwise, the obvious answer is to connect whatever needs the red pulse directly to whatever is producing the blue pulse. \$\endgroup\$
    – Dave Tweed
    Commented May 6, 2018 at 11:59

2 Answers 2

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As mentioned in the comments, you can only delay the blue pulse to match the red. One simple way to do it is with an RC lowpass, and some Schmitt gate, or a comparator, or whatever suits you. Here is an example:

example

The Schmitt trigger switches between ~1.666V and ~3.333V (some random values), and the comparator is fixed at 2.5V. You can also make the comparator with hysteresis. The values of the RC can be calculated to determine the delay.

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  • \$\begingroup\$ The R-C filter and Schmitt squaring circuit becomes quite difficult when the delay approaches the pulse width, as here. But the squaring circuit may help clean up after a lumped (L-C) delay. \$\endgroup\$
    – user16324
    Commented May 6, 2018 at 11:44
  • \$\begingroup\$ @BrianDrummond I have simply thrown in some values, but it looks like the OP wants more than half of the pulse width, which is ~75\$\mu\$s. Still, you're right, these values are hard (or very hard) to achieve in a real-case scenario. \$\endgroup\$
    – a concerned citizen
    Commented May 6, 2018 at 12:24
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Delay the blue signal in a delay line. If you can define a maximum frequency of interest, you can make (or buy) lumped L-C delay lines to do the job; otherwise you can simply use a length of coaxial cable, fed from (and terminated in) its characteristic impedance (usually 50 or 75 ohms).

As the delay appears to be about 8000 ns, the cable would need to be about 2/3 * 8000 feet long, or slightly over a mile.

I'd look more seriously at lumped-element delay lines. Here are some up to 5000 ns.

There are other analog technologies that can do this - mainly electroacoustic, such as SAW (Surface Acoustic Wave) or the mercury delay lines used in early computers. SAW delay lines for 64 uS used to be readily available standard components (used in PAL TV decoders), other sizes would probably be custom (and expensive in small quantity).

But there may be other approaches if only we knew more about what you were trying to do and why.

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