strategy for controlling the upper and lower limit of a pulse

yefj

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Hello, I have built the following circuit in LTSPICE.
I have two nets D_pre and D plots shown below currently my pulse at D from -1 to -7 i want to change Net D pulse to be -3 to -5.
What is the strategy to do it?
Thanks.




 

Seems to me an OpAmp could do the level shift and arbitrary G and
replace Q1 and Q2 and most of the passives around them. Does it have
to be discretes ?

Do you care about output Z ?


Regards, Dana.
 

Hello Dana, I prefer to understand the bit logic strategy if there a way with the PNP and resistors to control the pulse upper and lower level.
PNP is basically a switch I need to find the intuition of how to use resistor around it ( or add) to control these levels.
Thanks .
 
Last edited:

Consider your pulse-driving care-abouts. Accuracy
(initial, droop, load), settling time, overshoot....

You could like an op amp w/ limiter, you could like
a pair of regulated "supplies" (ref + filter) and an
analog switch if settling time is key and drive needed
is low.

You could like a voltage regulator with a little "funny
business" stuck into the feedback network.

But all of this is for you to figure out before the cut-and-try.
 

Something like this :



You can scale R's to get lower Power dissipation....


Regards, Dana.
 

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