AS5043
Data Sheet – Angular Output Tolerances
60
for slow mode
n =
rpm ⋅384μs
In practice, there is no upper speed limit. The only restriction is that there will be fewer samples per revolution as the
speed increases.
Regardless of the rotational speed, the absolute angular value is always sampled at the highest resolution.
Table 6: Speed Performance
Slow Mode
Fast Mode
(Pin Mode = 1)
(Pin Mode = 0 or open)
610rpm = 1024 samples / turn
1220rpm = 512 samples / turn
2441rpm = 256 samples / turn
etc…
610rpm = 256 samples / turn
1220rpm = 128 samples / turn
2441rpm = 64 samples / turn
etc…
18.5 Output Delays
The propagation delay is the delay between the time that the sample is taken until it is available as angular data. This
delay is 96µs in fast mode (pin Mode = high) and 384µs in slow mode (pin Mode = low or open).
The analog output produces no further delay, the output voltage will be updated as soon as it is available. Using the SSI
interface for data transmission, an additional delay must be considered, caused by the asynchronous sampling
(0….1/fsample) and the time it takes the external control unit to read and process the angular data from the AS5043.
18.5.1 Angular Error Caused by Propagation Delay
A rotating magnet will cause an angular error caused by the propagation delay.
This error increases linearly with speed:
esampling (deg) = 6∗rpm∗ pr.delay
where esampling = angular error [°]
rpm = rotating speed [rpm]
prop.delay = propagation delay [seconds]
Note: since the propagation delay is known, it can be automatically compensated by the control unit processing the data
from the AS5043.
18.6 Internal Timing Tolerance
The AS5043 does not require an external ceramic resonator or quartz. All internal clock timings for the AS5043 are
generated by an on-chip RC oscillator. This oscillator is factory trimmed to ±5% accuracy at room temperature (±10%
over full temperature range). This tolerance influences the ADC sampling rate:
18.6.1 Absolute Output; SSI Interface
A new angular value is updated every
96µs +/- 5% (Mode = 1) or
384µs +/- 5% (Mode = 0 or open)
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