| ??? 02/15/06 02:21 Modified: 02/15/06 02:40 Read: times |
#109995 - Include R8 in the feedback loop Responding to: ???'s previous message |
Do never connect a capacitor directly at output of an OPamp. This will cause instability and oscillation. So, if you remove C6, the 'noise' should disappear.
Potential at C20 is not constant but demonstrates that C20 is relevantly charged and discharged. This is a sign, that C20 is not big enough. One remedy is to increase C20. But much better is to include R8 in the feedback loop, like it's shown in figure 6 of this datasheet: http://www.analog.com/UploadedF..._413_e.pdf Keep everything unchanged, but include R8 in the feedback loop and add a 100nF cap (like C1 in figure 6) and a 10k resistor (like R3 in figure 6). R8 can be decreased to 100R. C20 should be a good tantal. Kai |
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| Looks ok but i am missing something | 01/01/70 00:00 | |
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| I just had a thought | 01/01/70 00:00 | |
| Include R8 in the feedback loop | 01/01/70 00:00 | |
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| Good idea | 01/01/70 00:00 | |
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| Congrets!! | 01/01/70 00:00 | |
| RE : Congrets!! | 01/01/70 00:00 | |
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