Re: Motorola 33794 electric field imaging IC

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

 >From what I can figure, it's basically the analog side of a multiport
capacitance meter. It's buffers, an oscillator, some good switches, and so
forth.  Reading through the applications info, the idea is that you feed the
signal out to one of 9 electrode, ground 7 electrodes, then measure the
current through the 8th connected through a resistor to ground. From that
you calculate the capacitance between the two electrodes (just like a DVM
measures capacitance)

Then, you can try some (or all) pairs of electrodes (72 max).


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Monday, March 10, 2003 7:57 PM
Subject: RE: Motorola 33794 electric field imaging IC


 > Original poster: "Wall Richard Wayne by way of Terry Fritz
<teslalist-at-qwest-dot-net>" <rwall-at-ix-dot-netcom-dot-com>
 >
 > Jim,
 >
 > I've read up on it, but it seems pretty electronically complicated for me.
 > THe concept is great though.
 >
 > RWW
 >
 >
 >  > Anybody fooled with the MC33794.. it's a thing used to image electric
 >  > fields, typically for air bag controllers, etc.
 >  >
 >  > It "generates a high purity sinewave, steers it to one of 9 external
 >  > electrodes and measures the resutlant field coupled into the non-driven
 >  > electrodes"
 >  >
 >  >
 >
http://e-www.motorola-dot-com/webapp/sps/site/prod_summary.jsp?code=MC33794&node
 > Id=0143597973b9G0
 >  >
 >  > The evm (KIT33794DHEVM) works at 125 kHz (of all frequencies to
 >  > choose!)  $138 from future-active-dot-com
 >  >
 >  > Here's the data sheet for the part:
 >  >   http://e-www.motorola-dot-com/brdata/PDFDB/docs/MC33794.pdf
 >  >
 >  > The part is $3 in Qty:1000+
 >  >
 >  >
 >
 >
 >
 > --- Richard Wayne Wall
 > --- rwall-at-ix-dot-netcom-dot-com
 >
 >