as5140 austriamicrosystems, as5140 Datasheet - Page 16

• Manufacturer Part Number: as5140
• Description: 10-bit 360? Programmable Magnetic Rotary Encoder For High Ambient Temperatures Up To 150?c
• Manufacturer: austriamicrosystems

AS5140H 10-BIT PROGRAMMABLE MAGNETIC ROTARY ENCODER
supply to the AS5140H, the pull-up resistors (>10kΩ)
from each pin must be connected to the positive supply
at pin 16 (VDD5V).
By hardware: PWM output: The PWM output is a
constant stream of pulses with 1kHz repetition frequency.
In case of power loss, these pulses are missing.
By hardware: Incremental outputs: In normal operation,
pins A(#3), B(#4) and Index (#6) will never be high at the
same time, as Index is only high when A=B=low.
However, after a power-on-reset, if VDD is powered up or
restarts after a power supply interruption, all three
outputs will remain in high state until pin CSn is pulled
low. If CSn is already tied to VSS during power-up, the
incremental outputs will all be high until the internal
offset compensation is finished (within t
15 Angular Output Tolerances
15.1 Accuracy
Accuracy is defined as the error between measured
angle and actual angle. It is influenced by several
factors:
As a sum of all these errors, the accuracy with centered
magnet = (Err
±0.5 degrees @ 25°C (see Figure 22).
Misalignment
accuracy. Figure 21 shows an example of a 3D-graph
displaying non-linearity over XY-misalignment. The
center of the square XY-area corresponds to a centered
magnet (see dot in the center of the graph). The X- and
Y- axis extends to a misalignment of ±1mm in both
directions. The total misalignment area of the graph
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the non-linearity of the analog-digital converters,
internal gain and mismatch errors,
non-linearity due to misalignment of the magnet
0
1
55
max
of
109
– Err
the
163
min
)/2 is specified as better than
magnet
217
271
linearity error with centered magnet [degrees]
further reduces
325
Err
PwrUp
m ax
379
Figure 22: Example of linearity error over 360°
).
433
487
the
www.austriamicrosystems.com
541
Err
595
m in
covers a square of 2x2 mm (79x79mil) with a step size of
100µm.
For each misalignment step, the measurement as shown
in Figure 22 is repeated and the accuracy
(Err
the Z-axis in the 3D-graph.
The maximum non-linearity error on this example is
better than ±1 degree (inner circle) over a misalignment
radius of ~0.7mm. For volume production, the placement
tolerance of the IC within the package (±0.235mm) must
also be taken into account.
The total nonlinearity error over process tolerances,
temperature and a misalignment circle radius of 0.25mm
is specified better than ±1.4 degrees.
The magnet used for this measurement was a cylindrical
NdFeB (Bomatec® BMN-35H) magnet with 6mm diameter
and 2.5mm in height.
649
Figure 21: Example of linearity error over XY misalignment
max
703
– Err
6
°
5
4
3
2
757
1
0
min
transition noise
)/2 (e.g. 0.25° in Figure 22) is entered as
811
Linearity Error over XY-misalignment [°]
865
y
919
973
-1000
-800
-600
-400
-200
0
200
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400
600
x
800
1000