AS5043 Programmable 360° Magnetic Angle Encoder

Revision 1.4, 04-Apr-06

www.austriamicrosystems.com

Page 6 of 26

AS5043

PROG

DO

CLK

CSn

CLK

µC

PROG

DO

CLK

CSn

PROG

DO

CLK

CSn

Data IN

CSn

AS5043

AS5043

Figure 6: Daisy Chain hardware configuration

9 Mode Input Pin

The absolute angular position is sampled at a rate of

10.4kHz (t=96µs) in fast mode and at a rate of 2.6kHz

(t=384µs) in slow mode.

These modes are selected by pin MODE (#2). The mode

input pin activates or deactivates an internal filter, which

is used to reduce the digital jitter and consequently the

analog output noise.

Activating the filter by pulling Mode = LOW or leaving it

open reduces the transition noise to <0.03° rms. At the

same time, the sampling rate is reduced to 2.6kHz and

the signal propagation delay is increased to 384µs. This

mode is recommended for high precision, low speed and

≤360° applications.

Deactivating the filter by setting Mode = HIGH increases

the sampling rate to 10.4kHz and reduces the signal

propagation delay to 96µs. The transition noise will

increase to <0.06° rms. This mode is recommended for

higher speed and full scale = 360° applications.

Switching

the

MODE

pin

affects

the

following

parameters:

Parameter

slow mode

(Pin MODE = 0 or

open)

fast mode

(Pin MODE = 1)

sampling rate

2.61 kHz

(383µs)

10.42 kHz

(95.9µs)

transition noise

(1 sigma)

≤ 0.03° rms

≤ 0.06° rms

propagation

delay

384µs

96µs

Startup time

20ms

80ms

Table 4: Mode pin settings

Pin MODE should be set at power-up. A mode change

during operation is not recommended.

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.

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)

Even

PAR

CSn

CLK

DO

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

18

16

CO F

LIN

OCF

Mag

INC

Mag

DEC

1

t

CLK FE

Angular Position Data

Status Bits

T

CLK/2

t

DO active

t

DO valid

D2

D9

D8

D7

3

Angular Position Data

Figure 7: Daisy Chain data transfer timing diagram