am8192b RLS, am8192b Datasheet - Page 10

• Manufacturer Part Number: am8192b
• Description: Angular Magnetic Encoder Ic
• Manufacturer: RLS

Data sheet
AM8192BD01_05
Issue 5, 14
Calculating the amount of noise:
The following graphs show the multiplication factors for peak noise against changing parameters. To calculate
the total amount of peak noise, multiply all factors by the nominal peak noise. The peak noise at nominal
conditions is 0.041°.
Default parameters:
* On Fig. 13, temperature coefficient of the magnet is included
Example calculation for a system operating at 80 °C, 10 nF filtering, 4.9 V power supply and 0.1 mm
increased distance would give us (reading from the graphs above):
Peak noise factor at 10 nF filtering = 1.35
Peak noise factor at 4.9 V power supply = 1.03
Peak noise factor at temperature 80 °C = 1.11
Peak noise factor at 0.1 mm increased distance = 1.06
Total peak noise = 0.041° x 1.35 x 1.03 x 1.11 x 1.06 = 0.067°
© 2009 RLS d.o.o.
3.5
2.5
1.5
0.5
1.8
1.6
1.4
1.2
0.8
0.6
4
3
2
1
0
2
1
0.1
-40
Fig. 13: Peak noise factor Vs Temperature *
22 nF filtering capacitors
Room temperature (22 °C)
5 V power supply
1.9 mm distance between top of the magnet and surface of the chip
Ø 4 x 4 mm diametrically polarized SmCo17 magnet
Fig. 11: Peak noise factor Vs Filtering
-20
th
January 2009
0
External filtering capacitors [nF]
20
1
Temperature [°C]
40
60
10
80
100
120
100
140
A
1.05
0.95
1.4
1.3
1.2
1.1
0.9
0.8
0.7
0.6
1.1
0.9
1
1
-0.5
Fig. 14: Peak noise factor Vs Distance change
4.75
Fig. 12: Peak noise factor Vs Power supply
Chip to the magnet distance change [mm]
-0.25
4.875
Power supply voltage [V]
associate company
5
0
5.125
0.25
5.25
0.5
10