AS5130ATST AMSCO [austriamicrosystems AG], AS5130ATST Datasheet - Page 31

• Manufacturer Part Number: AS5130ATST
• Description: 8 Bit Programmable Magnetic Rotary Encoder with Motion Detection & Multiturn
• Manufacturer: AMSCO [austriamicrosystems AG]

AS5130
Data Sheet - A p p l i c a t i o n I n f o r m a t i o n
Figure 26. 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
as the step size is smaller. For the AS5130, the quantization error is ± ½ LSB = ± 0.7º
Figure 27. Typical INL Error over 360º
Figure 27
includes the quantization error, transition noise and the system error. The total error is ~2.2º peak/peak (+/-1.1º).
The sawtooth-like quantization error
constant motion and there are an adequate number of samples available. The solid bold line in
moving average of 16 samples. The INL (intrinsic non-linearity) is reduced to from ~+/- 1.1º down to ~ +/-0.3º. The
averaging however, also increases the total propagation delay, therefore it may be considered for low speeds only or
adaptive; depending on speed
www.austriamicrosystems.com
shows a typical example of an error curve over a full turn of 360º at a given X-Y- displacement. The curve
+1/2 LSB
-0,5
-1,5
-1/2 LSB
1,5
0,5
-1
Quantization
1
0
0
Error
45
(see Position Error Over Speed: on page
Figure
(see Figure 26)
ideal function
90
INL including quantization error
26, a higher resolution system (right picture) has a smaller quantization error,
135
error
can be reduced by averaging, provided that the magnet is in
resolution
Revision 1.00
digitized
function
INL
low
Angle steps
+1/2 LSB
-1/2 LSB
180
Average (16x)
22).
225
ideal function
270
Figure 27
315
digitized
resolution
function
high
shows the
360
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