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Opamp problem

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bigfish256

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I have a four channel op amp (0745 LT1369CS is the top markings) I have a supplied 12V and a regulated 5V. Pin 1 is 5A with pin 2 as feedback. All of the other channels read 4.99-5.00V. Channel A is pulled low to ≈ 2.8V. I have raised the legs on channel A of the op amp to isolate it from the sensor board downstream. When I raised the legs and tied the output to the feedback I still get 2.8V. I have replaced the chip twice. Any one ever ran into this? It is supposed to put out 5V precision.
 
I am sorry those top markings don't return any search results, these do LT1369CS PBF-ND. Any information would be helpful. I believe that if you lift pins 1 and 2 and tie them together you should see a precision 5V. Is that incorrect?
 
Here is an attachment of the schematic I am working with.
 

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    Opamp circuit 1.JPG
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Perhaps it's oscillating. Do you have any decoupling caps on +12V to GND? Also, try 100Ω between the op amp output and your multimeter. The cap loading of the multimeter could be causing oscillation (not likely).
 
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Pin 1 is 5A with pin 2 as feedback.
What? You don't make any sense.

Channel A is pulled low to ≈ 2.8V.
Pulled low? By what? Do you mean that without a load pin 1 and pin 2 are +2.8V?
I have raised the legs on channel A of the op amp to isolate it from the sensor board downstream. When I raised the legs and tied the output to the feedback I still get 2.8V. I have replaced the chip twice. Any one ever ran into this? It is supposed to put out 5V precision.
If pin 3 is +5V and pin 1 and pin 2 are connected together the pin 1 and pin 2 should be +5V if the load current is 30mA or less.
 
I meant that channel A is low, not pulled low. It seems that it is being pulled low, but I can't figure out by what. I am clueless on this problem. Looking at the schematic I would assume that with 5v on pin 3 then pin 1 and 2 should be 5V when connected. I assumed that the problem was on the board. I have taken a brand new chip and soldered wire wrap from the legs and hooked them to a lab supply. It performed the same ≈ 2.8V. I really do not understand this problem. It says on the datasheet that it should operate on around 1.8V to 15V. I have looked at the datasheet and I don't see any other conditions that would keep it from operating correctly.
 
There are four .1 uf capacitors to filter noise on the output. We have realized that that is actually too much, seeing as how the data sheet only allows for 18 pf. However, this does not fix the problem.
 
There are four .1 uf capacitors to filter noise on the output. We have realized that that is actually too much, seeing as how the data sheet only allows for 18 pf. However, this does not fix the problem.
The LT1369 datasheet says it is stable for loads less than 1000pF. How did you come up with 18pF? The stability graph starts at 18pF and goes up. If you have 100nF loads, I would expect oscillation. I assume you remove the cap from +5A, and it still read 2.8V. (?)
Have you looked at the outputs with an oscilloscope?
 
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