AS5043ASSU austriamicrosystems, AS5043ASSU Datasheet - Page 25

• Manufacturer Part Number: AS5043ASSU
• Description: IC, MAGNETIC ROTARY ENCODER 10BIT SSOP16
• Manufacturer: austriamicrosystems

Specifications of AS5043ASSU

• Ic Function: Encoder IC
• Supply Voltage Range: 3V To 3.6V, 4.5V To 5.5V
• Operating Temperature Range: -40°C To +125°C
• Digital Ic Case Style: SSOP
• No. Of Pins: 16
• Msl: MSL 3 - 168 Hours
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AS5043
Data Sheet – Angular Output Tolerances
Figure 23: Example of Linearity Error over 360°
18.3 Transition Noise
Transition noise is defined as the jitter in the transition between two steps.
Due to the nature of the measurement principle (Hall sensors + Preamplifier + ADC), there is always a certain degree of
noise involved.
This transition noise voltage results in an angular transition noise at the outputs. It is specified as 0.06 degrees rms
(1 sigma)
These values are the repeatability of an indicated angle at a given mechanical position.
The transition noise has different implications on the type of output that is used:
18.4 High Speed Operation
18.4.1 Sampling Rate
The AS5043 samples the angular value at a rate of 10.42k samples per second (ksps) in fast mode and 2.61ksps in slow
mode.
Consequently, a new reading is performed each 96µs. (fast mode) or 384µs (slow mode).
At a stationary position of the magnet, this sampling rate creates no additional error.
Absolute Mode:
With the given sampling rates, the number of samples (n) per turn for a magnet rotating at high speed can be calculated
by
www.austriamicrosystems.com
n
=
-0.1
-0.2
-0.3
-0.4
-0.5
0.5
0.4
0.3
0.2
0.1
rpm
0
1
60
absolute output; SSI interface:
The transition noise of the absolute output can be reduced by the user by applying an averaging of readings. An
averaging of 4 readings will reduce the transition noise by 6dB or 50%, e.g. from 0.03°rms to 0.015°rms (1
sigma) in slow mode
analog output:
Ideally, the analog output should have a jitter that is less than one digit. In 360° mode, both fast or slow mode
may be selected for adequate low jitter.
In 180°, 90° or 45° mode, where the step sizes are smaller, slow mode should be selected to reduce the output
jitter.
*1
3 sigma represents 99.73% of readings.
⋅
*1
96
: statistically, 1 sigma represents 68.27% of readings,
in fast mode (pin MODE = high) and 0.03 degrees rms (1 sigma)
μ
55
s
for fast mode
109 163 217 271 325 379 433 487 541 595 649 703 757 811 865 919 973
Linearity Error with Centered Magnet [degrees]
Err max
Revision 1.80
Err min
*1
in slow mode (pin MODE = low or open).
transition noise
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