as5311 austriamicrosystems, as5311 Datasheet - Page 13

• Manufacturer Part Number: as5311
• Description: High Resolution Magnetic Linear Encoder
• Manufacturer: austriamicrosystems

AS5311
Data Sheet
Table 5: Magnetic field strength red-yellow-green indicators
7 Pulse Width Modulation (PWM) Output
The AS5311 provides a pulse width modulated output (PWM), whose duty cycle is proportional to the relative
linear position of the magnet within one pole pair (2.0mm). This cycle repeats after every subsequent pole pair:
The PWM frequency is internally trimmed to an accuracy of ±5% (±10% over full temperature range). This
tolerance can be cancelled by measuring the complete duty cycle as shown above.
Figure 10: PWM output signal
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Mag
All other combinations
INC
0
0
1
1
1
Status Bits
for digital position = 0 – 4094
Exception:
Position
DEC
Mag
0
1
0
1
1
=
LIN
(
t
0
0
0
0
1
t
on
on
⋅
+
4098
A linear position of 1999.5µm = digital position 4095
will generate a pulse width of t
t
off
>5F hex
<20 hex
20 hex-
3F hex
3F hex
3F hex
5F hex
M11..
)
MAG
M0
−
1
INCn
Mag
Off
Off
Off
On
On
n/a
1µs
DECn
Mag
Off
Off
Off
Off
On
n/a
Revision 1.00
on
Description
No distance change
Magnetic input field OK ( GREEN range, ~10…40mT peak
amplitude)
Distance increase; this state is a dynamic state and only
active while the magnet is moving away from the chip.
Magnitude register may change but regulates back to 3F hex.
Distance decrease; this state is a dynamic state and only
active while the magnet is moving towards the chip.
Magnitude register may change but regulates back to 3F hex.
YELLOW range: magnetic field is ~3.4….54.5mT.
The AS5311 may still be operated in this range, but with
slightly reduced accuracy.
RED range: magnetic field is <3.4mT (MAG <20) or >54.5mT
(MAG >5F).
It is still possible to operate the AS5311 in the red range, but
not recommended.
Not available
= 4097µs and a pause t
Hardware Pins
4097µs
4098µs
off
= 1µs
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