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three way buffer replication of a special kind on pulse

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There is a pulse shown in the picture.The pulse voltage are -2V to -5V and the width is 200ns.
Is there a component which could take this pulse and relpicate it three times?
Three outputs which are equal to the pulse i entered.
Thanks.

1721219023452.png
 
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Replicate w/o any phase shift between pulses ?

3 fast OpAmp voltage followers ? Or does solution need to be digital ?


Regards, Dana.
 
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Hello Dana, I have tried to use buffered opamp configuration of AD8034 as shown bellow.
As you can see my rise and fall time are getting worse.
is there a way to make the edges sharper?
Or if there is a digital component which will do a good job its also a great solution :)
My goal is to have -2 to -5 200n width input and gat the same pulse on the output as well but with rise and fall time as fast as possible.
maybe a flip flop or a latch could do the job?
1721224237899.png

1721224274466.png
 
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If you want edges sharper than original should work on source/original first.

AD8034 slew rate is worst case, 4V step, 55 V/uS.

What is source origin, eg. its circuit ?


Regards, Dana.
 
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I want to replicate the output .Unfortuney the source is not what is needed .
 
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Then I would use a comparator to gen a generic fast rise/fall waveform, then
use OpAmp followers with fast enough slew rate to meet your Tr, Tf time, which is ?
 
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Hello, 10ns rise and fall time would be the ideal :)
So I assume you want me to put - 2 and -5 for the supplie of the comparator .
What comparator do you recommend so I could try and simulate the ultra fast pulse :)
--- Updated ---

update:
Hello , I have tried to use the following comparator.
When 1>0 output is -5
When 1<3.3 output is -2
but on the output i get straight -1 .
Where did I go wrong?
Thanks.
1721240609567.png


1721240741040.png
 
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instead of an op amp, how about a transistor?
original signal to base, -2 at the collector, -5 at base
some resistors to limit the current
 
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That comparator develops a logic level output, not a -2 to -5 output. Nor does
it swing to its rails, read the datasheet Voh and Vol specs.

You want to swing 3V in 10 nS = 300 V / uS rate.

How accurate do the -2 & -5 V levels have to be ?

In your original pic you have ~ a Tr and Tf of 30 nS... so a faster OpAmp with
3 V / 30 nS or ~ 100V / nS or better would preserve the original rise and fall
time.....just a thought.

Also a factor in comparator performance is overdrive (typical example) :

1721247421772.png


What is currently chief cause of original Tr and Tf in your POST #1 ? Whats causing
it to be slower than you want ?
 
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Please look at datasheet and tell me what its swing will be on the supplies you
stipulated and answer your own question.

2 questions for you in POST # 10 and the answers are ?
 
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Why do people keep following this OP down their rabbit holes? They continuously post half-thought-out questions, fail to provide pertinent requirements, ignore advice from others, while they expend minimum effort in answering their own question.

Here's a solution to your ill-defined question: You want three identical copies of your signal? Use three wires.
 
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Hello Dana,
How accurate do the -2 & -5 V levels have to be ?
0.3V value innacuracy could be ok in the voltage levels.

What is currently chief cause of original Tr and Tf in your POST #1 ? Whats causing
it to be slower than you want ?

The AD8034 is the chief cause.
I tried to use LTC6253 i got a little better results.
Thanks.

1721401342190.png

1721401315881.png

--- Updated ---

Update:

LTC6269 gives a good result in a spice model but as you can see in the datasheet its supply is maximum 5.5V.
I need at least 7.5V supply.
Is there some good fast opamp with higher then 7.5V supply rating?

1721402786710.png
 
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Go to digikey.com, search on opamp, and start settings filters to select
slew rate, I/O voltage levels, bandwidth, slew rate.....to pick one or more
to try.


Regards, Dana.
 
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Hello Dana, LMH6654 is much better then AD8034 as shown in the plots below.
The LMH6654 is much higher BW and it prodices almost exact copy of th input.
But the problem is the supply voltage of the LMH6654.
on one hand the table below says that V+ - V- =+-6V
on the other they say V+ - V- 13.2.
Can it work with +6 -6 in the supplies ?
Maybe i could tried to do the supplies not simetric?
Thanks.

1721418827140.png
1721418658780.png


1721418175899.png

1721418337167.png
 
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Hello Dana , yes I posted this section too.
That means that plus supply is 6 and minus supply -6 , this difference is 12? Or
The difference is 6 .
On the maximal rating they say 13.2V.
So I am confused regarding if + 6 -6 is allowed because this is what I need :)

Also i have a problem that Vin=Vcc-0.5 at most.
and i am almost at that point.
I need some opamp with 800MHz BW and supply 14V range it will be great , ill try to look for one.
Thanks .
 
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I may be wrong I think OP is trying to preserved the -2 to -5 pulse, just replicate it and clean up Tr and Tf.....?
 
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