AS5030-ATSU austriamicrosystems, AS5030-ATSU Datasheet - Page 34

• Manufacturer Part Number: AS5030-ATSU
• Description: IC ENCODER ROTARY 8-BIT 16-TSSOP
• Manufacturer: austriamicrosystems
• Type: Linear, Rotary Encoder - Programmabler

Specifications of AS5030-ATSU

• Sensing Range: 23.6mT ~ 44.5mT
• Voltage - Supply: 4.5 V ~ 5.5 V
• Current - Supply: 14mA
• Current - Output (max): 4mA
• Output Type: Digital, PWM
• Features: Programmable
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 16-TSSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AS5030
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
8.8 Accuracy of the Encoder System
This chapter describes which individual factors influence the accuracy of the encoder system and how to improve them.
Accuracy is defined as the difference between measured angle and actual angle. This is not to be confused with resolution, which is the smallest
step that the system can resolve.
The two parameters are not necessarily linked together. A high resolution encoder may not necessarily be highly accurate as well.
8.8.1 Quantization Error
There is however a direct link between resolution and accuracy, which is the quantization error:
Figure 28. Quantization Error of a Low Resolution and a High Resolution System
The resolution of the encoder determines the smallest step size. The angle error caused by quantization cannot get better than ± ½ LSB. As
shown in
For the AS5030, the quantization error is ± ½ LSB = ± 0.7°
Figure 29. Typical INL Error Over 360°
www.austriamicrosystems.com/AS5030
-0,5
-1,5
Figure
1,5
0,5
-1
1
0
0
28, a higher resolution system (right picture) has a smaller quantization error, as the step size is smaller.
+½ LSB
-½ LSB
Quantization
Error
45
INL including quantization error
ideal function
90
resolution
low
135
error
function
digitized
INL
Angle steps
Revision 2.1
+½ LSB
-½ LSB
180
Average (16x)
225
ideal function
270
resolution
high
digitized
function
315
360
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