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AS5311

Datasheet - D e t a il e d D es c r i pt io n

7.2 Incremental Output Hysteresis

Figure 5. Hysteresis Illustration

To avoid flickering incremental outputs at a stationary magnet position, a hysteresis is introduced.

In case of a movement direction change, the incremental outputs have a hysteresis of 2 LSB. For constant movement directions, every magnet

position change is indicated at the incremental outputs (see Figure 4). If for example the magnet moves from position “x+3” to “x+4”, the

incremental output would also indicate this position accordingly.

A change of the magnet’s movement 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 movement, the incremental outputs will again be updated with every change of the

magnet position.

7.3 Synchronous Serial Interface (SSI)

The Serial interface allows data transmission of the 12-bit absolute linear position information (within one pole pair = 2.0mm). Data bits D11:D0

represent the position information with a resolution of 488nm (2000µm / 4096) per step. CLK must be high at the falling edge of CSn.

Figure 6. Synchronous Serial Interface with Absolute Angular Position Data

Magnet Position

Hysteresis:

2 steps

X +2

Incremental

Output

Indication

Movement right

left

X +4

X

X

X +2

X +4 X +5

X +3

X +1

X +1

X +3

-->

D11

1

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

OCF

COF

LIN

Mag

INC

Mag

DEC

Even

PAR

D11

1

18

8

Status Bits

Angular Position Data

CSn

DO

CLK