AS5040 PB austriamicrosystems, AS5040 PB Datasheet - Page 13

• Manufacturer Part Number: AS5040 PB
• Description: BOARD PROGRAM AS5040
• Manufacturer: austriamicrosystems

Specifications of AS5040 PB

• Module/board Type: ZIF Socket
• For Use With/related Products: AS5000 Programmer, AS5040
• Lead Free Status / RoHS Status: Lead free by exemption / RoHS compliant by exemption
• Other names: AS5045 PB; AS5140H PB; AS5145 PB

AS5040
Data Sheet
Figure 8: Incremental Output Modes
Incremental Power-up Lock Option
After power-up, the incremental outputs can optionally be locked or unlocked, depending on the status of the CSn pin:
CSn = low at power-up:
CSn = high or open at power-up:
Incremental Output Hysteresis
To avoid flickering incremental outputs at a stationary magnet position, a hysteresis is introduced.
In case of a rotational direction change, the incremental outputs have a hysteresis of 2 LSB.
Regardless of the programmed incremental resolution, the hysteresis of 2 LSB always corresponds to the highest
resolution of 10 bit. In absolute terms, the hysteresis is set to 0.704 degrees for all resolutions.
For constant rotational directions, every magnet position change is indicated at the incremental outputs (see
Figure 9). If for example the magnet turns clockwise from position „x+3“ to „x+4“, the incremental output would also
indicate this position accordingly.
A change of the magnet’s rotational direction back to position „x+3“ means, that the incremental output still remains
unchanged for the duration of 2 LSB, until position „x+2“ is reached. Following this direction, the incremental outputs
will again be updated with every change of the magnet position.
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Q uad A/B-M ode
Step / Dir-Mode
CSn has an internal pull-up resistor and must be externally pulled low (R
the incremental outputs (A, B, Index) will be high until the internal offset compensation is finished.
This unique state (A=B=Index = high) may be used as an indicator for the external controller to shorten the
waiting time at power-up. Instead of waiting for the specified maximum power up-time (0), the controller can
start requesting data from the AS5040 as soon as the state (A=B=Index = high) is cleared.
In this mode, the incremental outputs (A, B, Index) will remain at logic high state, until CSn goes low or a low
pulse is applied at CSn. This mode allows intentional disabling of the incremental outputs until for example the
system microcontroller is ready to receive data.
Index
A
B
Dir
CSn
LSB
t
Increm ental outputs valid
Clockwise cw
Revision 2.10
Zero Position
M echanical
Index=0
Index=1
1LSB
3 LSB
Rotation Direction
Change
ext
t
≤ 5kΩ). If Csn is low at power-up,
H yst =
2 LSB
D ir valid
Zero Position
Counterclockwise ccw
M echanical
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