ATS673 Allegro MicroSystems, Inc., ATS673 Datasheet - Page 11

• Manufacturer Part Number: ATS673
• Description: Self-calibrating Tpos Gear Tooth Sensor Optimized For Automotive Cam Sensing Applications Optimized For Automotive Cam Sensing Applications
• Manufacturer: Allegro MicroSystems, Inc.

ATS673 and
ATS674
AGC (Automatic Gain Control)
The AGC feature is implemented by a unique patented self-
calibrating circuitry. After each power-on, the devices measure
the peak-to-peak magnetic signal. The gain of the sensor is then
Figure 7. Effect of AGC. The upper panel shows the magnetic gradient detected at the Hall element, with no amplification.
The lower panel displays the corresponding internal processed signal, V
performance by the rest of the circuits that reference this signal.
Self-Calibrating TPOS Gear Tooth Sensor Optimized
600
500
400
300
200
100
2.0
1.5
1.0
0.5
0
0
Internal Analog Signal after AGC Versus Target Edge Position
0
0
10
10
Magnetic Flux Density Versus Target Edge Position
20
20
for Automotive Cam Sensing Applications
30
30
Target Rotation (°)
Target Rotation (°)
AG (mm):
40
40
AG (mm):
2.50
3.00
3.50
1.50
2.00
2.50
3.00
3.50
1.50
2.00
adjusted, keeping the internal signal amplitude constant over the
air gap range of the device. This feature ensures that operational
characteristics are isolated from the effects of changes in AG.
The effect of AGC is shown in figure 7.
50
50
PROC
. This normalized electrical signal allows optimal
60
60
70
70
80
80
115 Northeast Cutoff, Box 15036
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 [phone]
www.allegromicro.com
90
90
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