AS5043

Data Sheet – Daisy Chain Mode

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Revision 1.80

9 – 36

10 Daisy Chain Mode

The Daisy Chain Mode allows connection of several AS5043’s in series, while still keeping just one digital input for data

transfer (see “Data IN” in Figure 6 ). This mode is accomplished by connecting the data output (DO; pin 9) to the data

input (PROG; pin 8) of the subsequent device. An RC filter must be implemented between each PROG pin of device n

and DO pin of device n+1, to prevent then encoders to enter the alignment mode, in case of ESD discharge, long cables,

not conform signal levels or shape. Using the values R=100R and C=1nF allow a max. CLK frequency of 1MHz on the

whole chain. 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 * (16+1) bits:

e.g. 34 bit for two devices, 51 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 (D9),

etc… (see Figure 7).

Figure 6: Daisy Chain Hardware Configuration

CSn

PROG

DI

CLK

CSn

DO

CLK

CSn

DO

CLK

PROG

CSn

DO

CLK

PROG

100R

100R

1nF

1nF

GND

GND

GND

MCU

AS5043

AS5043

AS5043

Figure 7: Daisy Chain Data Transfer Timing Diagram

Even

PAR

CSn

CLK

DO

D 9

D8

D7

D6

D 5

D 4

D 3

D 2

D1

D0

18

16

COF

LIN

OCF

Mag

IN C

Mag

DEC

1

A ngular Position D ata

Status Bits

D

2

D9

D8 D7

3

A ngular Position D ata