Thread: Denso Window Motors, Warning - Don't use with Jaguars !
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Unread 07-03-2010, 22:09
diviney diviney is offline
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Re: Denso Window Motors, Warning - Don't use with Jaguars !
Mike:

I just took a very crude look at the motor impedance. I realize the "small signal" impedance will differ from the dynamic impedance with real loads / drive levels, but this was just a simple look with a signal generator and a scope.

The DC resistance is around 2 ohms. The signal generator test showed a flat 4.5 ohms from around 100 Hz, up through 1 KHz. Above this, the impedance increases kind of linearly. It's about 40 ohms at the 15 KHz switching rate of the Jag. Beyond this, there is what appears to be a parallel resonance with the impedance peaking to 200 ohms at 90 KHz.

I wonder if a "filter capacitor" would help this?

Is Luminary still the right POC, or is it now through TI somehow? It's academic at this point, we are changing to the Victor, but an interesting question nontheless.

-Tom