WEBVTT
Kind: captions
Language: en

00:00:02.640 --> 00:00:03.600
Hello.

00:00:03.600 --> 00:00:07.540
We have a first look at NVE's
new fast, accurate, and simple

00:00:07.540 --> 00:00:11.180
ASR002 Smart TMR Angle Sensor.

00:00:11.620 --> 00:00:12.940
For a demonstration,

00:00:12.940 --> 00:00:16.300
We have a 12-volt, 13000 RPM race-car motor

00:00:16.300 --> 00:00:18.000
spinning an inexpensive

00:00:18.000 --> 00:00:19.720
diametrical ferrite magnet.

00:00:20.620 --> 00:00:21.920
The magnet is glued onto

00:00:21.920 --> 00:00:23.660
a hand-drilled plastic hub.

00:00:24.500 --> 00:00:25.440
It's not extremely precise,

00:00:25.760 --> 00:00:26.840
but it doesn't have to be

00:00:26.840 --> 00:00:28.060
since these sensors

00:00:28.060 --> 00:00:31.260
have a wide tolerance for misalignment.

00:00:31.260 --> 00:00:35.900
The sensor is mounted on one of our 
TDFN evaluation boards,

00:00:35.900 --> 00:00:42.320
and connected to an Arduino via SPI.

00:00:42.320 --> 00:00:44.140
There are two outputs from the Arduino:

00:00:44.140 --> 00:00:46.060
the absolute angle, generated by

00:00:46.060 --> 00:00:49.860
a simple R/2R resistor array
connected to an oscilloscope;

00:00:50.940 --> 00:00:53.080
and a tachometer PWM output

00:00:53.080 --> 00:00:56.060
connected to a meter.

00:00:56.060 --> 00:00:57.540
We'll start the motor at low speed...

00:01:06.960 --> 00:01:08.240
Even at full speed,

00:01:08.240 --> 00:01:13.640
the sensor is tracking not just the speed,

00:01:13.640 --> 00:01:18.780
but the angular position within two degrees.

00:01:19.220 --> 00:01:21.100
We can misalign the sensor

00:01:21.100 --> 00:01:22.740
quite a bit and it still works.

00:01:24.780 --> 00:01:25.500
You can see

00:01:25.500 --> 00:01:28.160
it has a wide air-gap tolerance.

00:01:30.840 --> 00:01:33.500
And the ASR002 reads absolute--

00:01:33.500 --> 00:01:35.020
not incremental--position.

00:01:35.400 --> 00:01:36.640
So if we cycle the power,

00:01:37.160 --> 00:01:41.280
it comes up with the correct angle.

00:01:41.289 --> 00:01:46.080
Don't try that with an incremental encoder!

00:01:46.080 --> 00:01:51.640
Here's the demo circuit:

00:01:51.640 --> 00:01:54.640
And here's the Arduino software:

00:01:54.640 --> 00:01:58.000
Reading the angle,
is a simple two-byte sequence.

00:01:58.000 --> 00:01:59.600
We write two “0” bytes,

00:01:59.600 --> 00:02:03.160
then continuously read the two-byte angle.

00:02:03.160 --> 00:02:04.980
Here we output the angle to the 'scope...

00:02:07.160 --> 00:02:09.560
...here we calculate the RPM for the tachometer

00:02:12.380 --> 00:02:15.400
Key ASR002 specifications are:

00:02:15.400 --> 00:02:17.240
2 degree accuracy;

00:02:17.240 --> 00:02:19.280
0.1-degree precision;

00:02:19.280 --> 00:02:21.360
Wide magnetic field operating range;

00:02:21.360 --> 00:02:22.480
High speed;

00:02:22.480 --> 00:02:23.760
Low power;

00:02:23.760 --> 00:02:27.520
Full −40°C to +125°C operating range;

00:02:27.520 --> 00:02:29.140
and it's ultraminiature.

00:02:32.080 --> 00:02:34.640
Call, click, or e-mail us for more information,

00:02:34.640 --> 00:02:40.000
or to buy ASR002 angle sensors and evaluation kits.