Hi,
First , thanks to gootee for loads of help on the previous post (still ongoing).
I'm posting this as a new topic as it is kind of a separate issue, and might be of interest to someone else in future, who wouldn't find it hidden in the previous post.
I've attached 2 LTspice circuits for an amp for a strain gauge. The first one works fine, simulating the strain gauge's output with voltage V3. The second one has a wheatstone bridge with the resistances present in my strain gauge. But it doesn't work.
I just get flat horizontal lines, indicating that the voltage doesn't change as R12 goes from 1000 to 1002 ohms. I usually do well with googling a solution, but can't find anything that explains this.
I've attached models for both the IC's in case that's needed, too.
Can anyone enlighten me? It looks right, so why doesn't it work?
Richard B
First , thanks to gootee for loads of help on the previous post (still ongoing).
I'm posting this as a new topic as it is kind of a separate issue, and might be of interest to someone else in future, who wouldn't find it hidden in the previous post.
I've attached 2 LTspice circuits for an amp for a strain gauge. The first one works fine, simulating the strain gauge's output with voltage V3. The second one has a wheatstone bridge with the resistances present in my strain gauge. But it doesn't work.
I just get flat horizontal lines, indicating that the voltage doesn't change as R12 goes from 1000 to 1002 ohms. I usually do well with googling a solution, but can't find anything that explains this.
I've attached models for both the IC's in case that's needed, too.
Can anyone enlighten me? It looks right, so why doesn't it work?
Richard B
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