Re: Resistor pulse handling?

Robert Baer wrote:
Since you definitely are not considering carbon composition resistors, then decades of experience with them is not useful. 

I am aware of their pulse handling capability.  Trouble is tolerance.

Hmm. Perhaps it would work anyway, since the carbon component of the total resistance into the diff amp would be a very small one.

However, I have discovered that my fears regarding screwing the performance of the diff amp are unwarranted, and that I can use a larger SMT resistance that is still within it's surge rating.

Perhaps the following compromise can be made.
1) start with a 100 ohm resistor from the source to node 1 that has a (filter) capacitor to ground; set the capacitor value to ten percent of the original calculated value. Peak pulse dissipation is fairly low, as there is less energy in the harmonics.
2) from node 1 to node 2 use a 200 ohm resistor and at node 2 use a capacitor that is 40 percent of the original calculated value. Do not know energy (spectrum) content of what flows thru resistor thru capacitor, but some whiz could do the math. I would dare say that energy may be in the same ballpark.
3) from node 2 to node 3 use a 200 ohm resistor and at node 3 use a capacitor that is 80 percent of the original calculated value. Do not know energy (spectrum) content of what flows thru resistor thru capacitor, but some whiz again could do the math. Guess in similar ballpark.
The idea is to dissipate the fastest stuff first, and do the rest later; spreading the energy in steps.
The values may need adjustment, but the idea is given for evaluation, not as an exact solution. 

Interesting method.  Can't afford the space for a lot of parts though.

Alternate method: use a ferrite bead in series with the source to the bypass node; ther aer SMT versions as well as leaded versions. 

Good to keep in mind as well.


Thanks for the reply.


Good day!





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