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AS5030

Datasheet - Detailed Descri p ti on

7.11 2-Wire Daisy Chain Mode

The AS5030 can also be connected in 2-wire Daisy Chain mode, requiring only two signals (Clock and Data) for any given number of daisy-

chained devices. Note that the connection of all devices except the last device is the same as for the 3-wire connection (see Figure 17). The last

device must have pin C2 (#15) set to ‘high’ and feeds the DX signal to CS of the first device.

Again, each device should be buffered with a 100nF cap (shown only for the last device).

The total number of serial bits is: n*21, where n is the number of connected devices. Note that this configuration requires one extra clock (#1) to

initiate the generation of the CS signal for the first device. After reading the last device, the communication must be reset back to the first device

by introducing a timeout of CLK (no rising edge for >24µs)

Figure 19. 2-wire Daisy Chain Mode

Figure 20. Timing Diagram in 2-wire Daisy Chain Mode

#1

100n

CS

CLK

DI O

+5 V

VDD

VSS

VSS

C 2

VDD

VDD

13

11

10

12

15

C1

VSS

3

14

I/O

Output

DX

#2

CS

CLK

DI O

C2

VDD

13

11

10

12

15

C1

VSS

3

14

DX

(last device)

CS

CLK

DI O

C2

VDD

13

11

10

12

15

C1

VSS

3

14

DX

AS5030

Micro

Controller

AS5030

AS5030

CLK

CS (#1)

AS 5030 # 1

CMD 3

DIO

12

3

4

56

78

CMD 1

CMD 2

CMD 0

D15

D14

CMD 4

CMD 3

21

22

23

24

25

26

CMD 1

CMD 2

CMD 0

D 15

D14

CMD 4

27

28

29

D0

CMD 3

42

43

44

CMD 2

CMD 4

D0

AS5030 # 2

AS5030 # 3

CS (#2)

CS (#3)

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