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AS5045B

Datasheet - Detailed Descr i p ti on

Figure 7. Hysteresis Window for Incremental Outputs

CSn is low (internal Pull Up) the first time. In quadrature mode A = B = Index = high indicates an invalid output. If the interpolator recognizes a

difference larger than 128 steps between two samples it holds the last valid state. The interpolator synchronizes up again with the next valid

difference. This avoids undefined output burst, e.g. if no magnet is present.

8.3 Daisy Chain Mode

The Daisy Chain mode allows connection of several AS5045Bs in series, while still keeping just one digital input for data transfer (see “Data IN”

in Figure 8). This mode is accomplished by connecting the data output (DO; pin 9) to the data input (PDIO; pin 8) of the subsequent device. The

serial data of all connected devices is read from the DO pin of the first device in the chain. The length of the serial bit stream increases with every

connected device, it is n * (18+1) bits: n= number of devices. e.g. 38 bit for two devices, 57 bit for three devices, etc.

The last data bit of the first device (Parity) is followed by a dummy bit and the first data bit of the second device (D11), etc. (see Figure 9).

Figure 8. Daisy Chain Hardware Configuration

Magnet Position

Hysteresis :

0.35°

X +2

Incremental

Output

Indication

Clockwise Direction

Counterclockwise Direction

X +4

X

X

X +2

X +4 X +5

X +3

X +1

X +1

X +3

X +6

X +5

X +6

CSn

CSn

CSn

CSn

CLK

CLK

CLK

CLK

Data IN

AS5045B

1

AS5045B

2

AS5045B

last Device

µC

DO

DO

DO

PDIO

PDIO

PDIO