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Opamp - comparator

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It should be noted that I made an error in my description, the bridge PFETs are on when there is no torque which provides dynamic brake to stop bump steering and hold the steering in it's last position and then turned off prior to the NFET being turned on
hi,
Check this clip from your box circuit, is the 430R connected in series with that 10Kpot.?? because you are showing an LED in the same path.?

What are the OPA comps types.?

I have a working LTspice sim of the 'boxes' section and a the14v/8v/2.5v
 

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hi,
Look at these images for the 'draft' version of your 'boxes' in LTspice.
 

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hi,
Check this clip from your box circuit, is the 430R connected in series with that 10Kpot.?? because you are showing an LED in the same path.?

What are the OPA comps types.?

I have a working LTspice sim of the 'boxes' section and a the14v/8v/2.5v

LM393 Comp, missed putting a connection there. 8v is an LM317
 

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LM393 Comp, missed putting a connection there. 8v is an LM317
I guessed it may be a LM393, thats what I used.

Look at the sim images I posted.

EDIT:
Sim with the +8V added to the Red led.
 

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Last edited:
All sim images in post 22 show the missing connection that was corrected in post 24, of particular interest to me would the I(V2), with the 8 V sitting on the 2.4 V zener, my mid point adjustment becomes 5.2 for the rest of the circuit and the only controlling input voltage that will vary with battery voltage will be the amplitude of the triangle wave. It's looking like the 8 v sitting on the 2.4 v zener will work, can you attach the .asc file for me, please. Still thinking, looking, changing and testing new ideas.
Thank You,
Jeff
 
All sim images in post 22 show the missing connection that was corrected in post 24, of particular interest to me would the I(V2), with the 8 V sitting on the 2.4 V zener, my mid point adjustment becomes 5.2 for the rest of the circuit and the only controlling input voltage that will vary with battery voltage will be the amplitude of the triangle wave. It's looking like the 8 v sitting on the 2.4 v zener will work, can you attach the .asc file for me, please. Still thinking, looking, changing and testing new ideas.
Thank You,
Jeff

hi,
Attached asc file [with the +8V mod].

I would like to see any of the asc files you create.
The LM393 model is from the LTS Yahoo user group site.

BTW: R20 is to that pin on the triangle gen
 

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hi,
Attached asc file [with the +8V mod].

I would like to see any of the asc files you create.
The LM393 model is from the LTS Yahoo user group site.

BTW: R20 is to that pin on the triangle gen

R20, saw that after a minute, I think I've come up with another change, I'll post it if it works out,
I just found this asc and modified it from a UJT oscillator to what I have in the circuit and adjusted values to demonstrate function, so what's in the asc is not necessarily what's on the circuit board.
After I did the modifications, I tried to attach it, but couldn't find it with windows explorer, so I had to open it back up with spice and save it to my desktop, It shows that it is locked, which I think means only spice can see it. Do you know what going on with spice doing that? Windows 7
Got a new computer a for Christmas and haven't got all things working just yet, Spice is one of them.
 

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Latest change, did away with zener, 8 volt goes to bridge only (22.65 ma).
My biggest problem was coming up with enough connector pins in the enclosure box and on the circuit board. Had to drill holes in the circuit board and replace the 8 pin socket and plug with a 12, couldn't do anything with the box so I spliced into the key wire going to the box.
Look good at this point.
Jeff
 

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hi,
Downloaded your latest attachments, will check them over.

When you finalise the design I would recommend adding noise/RF filtering between the bridge and the IA, various examples of filters are shown in the IA datasheets. Also a simple R/Cap filter on the output of the IA would be a good idea.
I'm assuming also as its a 'mobile' piece of kit powered from a 12V vehicle battery, so reverse voltage and good power rail filtering will be essential
 
Jeff

Sent you a PM with some junk I have you may be able to use for your strain gauge experimenting. Yours if you can use the stuff. Let me know.

Ron
 
Mobile? Yes, definitely, **broken link removed** This is a link to my Trooper if you would like to browse them.
Jeff

hi,
Nice pic, is that you at the wheel.?

BTW: perhaps a naive question, but what is the project that you are working on, going to do,?
 
Yes, that's me, it's for the steering on the above vehicle.
Jeff
 
Yes, that's me, it's for the steering on the above vehicle.
Jeff

Had a few problems with the PC due to downloading a RS232 program, damn thing corrupted all my serial and parallel port drivers settings, could not reinstall, had to use my backup hard drive.!!
 
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