Thread: Some 2007 KOP Gyro Performance Data
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Unread 26-03-2007, 18:13
yoyodyne yoyodyne is offline
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AKA: Greg Smith
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Re: Some 2007 KOP Gyro Performance Data
Joel,

There is an op-amp on the module. We did some analysis on the A/D input impedance to try to figure out why a 100K pot we were using looked more log than linear. Turned out that it wasn't a problem charging the A/D 25pf cap it was the pot. IFI did slap a .047uf cap with a 1K series resistor which has a time constant of 47us. Even with a 100K source impedance the time constant is still under 5ms. The A/D data sheet shows about a 40ms delay for the gyro output to come up to full rate. Our 100Hz sample rate adds up to an additional 10ms of delay. If I have some time I'll monitor the response of the analog output on a scope and see if it does have anything to do with driving the RC input pin.

Greg