WEBVTT

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Hi, I'm Chris Olson with NVE Corporation.
Today we're demonstrating

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NVE's unique analog magnetometer sensors.
We'll sense the field

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from a ceramic magnet versus distance
with magnetometer chips

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connected to an oscilloscope.

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First we'll test an AA004-02E sensor,

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which has a relatively high saturation field
of 50 Oersteds,

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but relatively low sensitivity of
one millivolt per Volt per Oersted.

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Here's the demonstration:

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The magnet is

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moved back and forth
by a linear stepper motor,

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driven by an Arduino board.

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We have a large signal,
even with no amplification.

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Here's the same plot converted to distance:

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The magnet looks like a dipole,

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so the field drops
with the cube of the distance.

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Here's a curve fit to a cube law
It's a pretty close fit.

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It restores your faith in physics.

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Another point to note is the sensor output

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is very repeatable with very little hysteresis.

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If we take the right side of the scope trace,

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which is the magnet getting farther away,
and flip it over the left side,

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which is the magnet getting closer,

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They line up almost perfectly.

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Now let's look at a high sensitivity sensor.

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This is an AAH002,

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which has a nominal sensitivity
of 15 millivolts per volt per Oersted,

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or about 15 times more sensitive
than the AA004 we tested before.

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With this magnet,
the sensor saturates if we get too close,

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so we'll run the magnet starting
more than an inch away.

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Even over two inches away,
we still have plenty of signal.

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So to the "lab results" are in:
NVE Analog Sensors

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have high sensitivity,
and low hysteresis

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over a wide magnetic range
They're also fast,

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and operate over a wide temperature range.

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Click, e-mail, or call us for more information,

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or to order parts or evaluation kits.