In Reply to: Re: Great topic!! -- one question posted by Dan Banquer on March 10, 2004 at 03:25:05:
Dan : ""To date: I have typically found the coupled signal 90 degrees out of phase with the main signal. It certainly looks to be capacitively coupled from what I see on the scope.""Hmmmm...I seem to remember some thing about collapsing magnetic fields...oh yah..:-)
When a wire stores energy, in the form of the magnetic field around it, the storage lags the current by 90 degrees. When it is released, it also lags..by 90 degrees.
The lower the impedance of the circuit loop, the larger the B dot error becomes w/r to the signal.
Not only are star grounding techniques a good thing, but you also have to pay attention to the field induced voltages. If not, error signals will creep in. For high accuracy, signal grounds must be routed orthogonal to the power ground.
Cheers, John
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Follow Ups
- Um...Dan? - jneutron 05:57:00 03/10/04 (8)
- Re: Um...Dan? - Dan Banquer 06:14:24 03/10/04 (7)
- Re: Um...Dan? - jneutron 06:30:07 03/10/04 (6)
- Re: Um...Dan? - Dan Banquer 06:49:43 03/10/04 (5)
- Re: Um...Dan? - jneutron 07:03:31 03/10/04 (1)
- Re: Um...Dan? - Dan Banquer 07:26:19 03/10/04 (0)
- In addition - Dan Banquer 07:02:54 03/10/04 (2)
- Re: In addition - jneutron 07:06:59 03/10/04 (1)
- Re: In addition - Dan Banquer 07:28:24 03/10/04 (0)