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Revision 2.4

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AS5030

Datasheet - Detailed Descr i p ti on

7.3 Serial 3-Wire Read-only Connection

If the AS5030 is only used to provide the angular data (no power down or OTP access) this simplified connection is possible. The Chip Select

(CS) and Clock (CLK) connection is the same as in the R/W mode, but only a digital input pin (not an I/O pin) is required for the DIO connection.

As the first 5 bits of the data transmission are command bits sent to the AS5030, both the microcontroller and the AS5030 are configured as

digital inputs during this phase. Therefore, a pull-down resistor must be added to make sure that the AS5030 reads “00000” as the first 5 bits

which sets the Read_Angle command.

All further application examples are shown in R/W mode, however read-only mode is also possible, unless otherwise noted.

Figure 6. SSI Read-only Serial Data Transmission

Figure 7. Timing Diagram in 2-wire and 3-wire SSI Mode

Table 4. Serial Bit Sequence (16-bit read/write)

Read

D20 D19 D18 D17 D16 D15 D14 D13 D12 D11 D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

C2

lock

AGC

Angle

D5

D4

D3

D2

D1

D0

D7

D6

D5

D4

D3

D2

D1

D0

100 n

CS

CLK

DI O

+5 V

VDD

VSS

VSS

C 2

VDD

VDD

13

11

10

12

15

C1

VSS

3

14

Input

10 k ...

100 k

Output

Output

Micro

Controller

AS5030

CLK

CS

DIO

D15

t9

command phase

data phase

t10

DIO

DIO write

t1

DIO read

12

3

4

5

6

7

21

8

D12

20

D14

D13

D0

D1