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AS5134

Datasheet - Detailed Descr i pti on

7.3 Serial 3-Wire Read-only Connection

This connection is possible when the AS5134 is only used to provide the angular data (no power down or OTP access). The Chip Select (CS)

and Clock (DCLK) 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 AS5134, both the microcontroller and the AS5134 are configured as digital

inputs during this phase. Therefore, a pull-down resistor must be added to make sure that the AS5134 reads “00000” as the first 5 bits, which

sets the Read_Angle command.

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

Figure 5. SSI Read-only Serial Data Transmission

Table 6. 2-or 3-wire Read-only Serial Bit Sequence (21bit read)

Command

Read Data

C4

C3

C2

C1

C0

D15 D14 D13 D12 D11 D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

0

0

0

0

0

lock

AGC

Angle

+5V

VDD

VDD

CS

DCLK

DIO

VSS

VSS

C2

100nF

VSS

VDD

Input

Output

Output

10k…

100k

1

2

3

4

5

6

7

21

20

D15

D14

D1

D0

DCLK

DIO

CS

DIO

command phase

data phase

t1

t9

t10

DIO read

DIO write

8

D13

D12