AS5043 Programmable 360° Magnetic Angle Encoder

Revision 1.4, 04-Apr-06

www.austriamicrosystems.com

Page 10 of 26

AS5043 Demoboard

+

7

2

3

4

5

6

1

10n

1µF

µC

only required for

OTP programming

OTP: keep these wires as

short as possible

max. length = 2 inches (5cm)

GND

PROG

CSN

DO

CLK

5VUSB

VDD3V3

VSS

+

10µF

2

3

1

GND

VSS

VPROG

7.5 … 8.0V

only required for

OTP programming

connect to USB

interface on PC

VOUT_EXT

8

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

1

MagRngn

Mode

CSn

CLK

NC

DO

VSS

Prog_DI

DACref

DACout

FB

Vout

NC

NC

VDD3V3

VDD5V

AS5043

IC1

Figure 12: OTP programming hardware connection of AS5043 (shown with AS5043 demoboard)

12.1 Zero Position Programming

The AS5043 allows easy assembly of the system, as the

actual angle of the magnet does not need to be

considered. By OTP programming, any position can be

assigned as the new permanent zero position with an

accuracy of 0.35° (all modes).

Using the same procedure, the AS5043 can be calibrated

to assign a given output voltage to a given angle. With

this approach, all offset errors (DAC + OPAMP) are also

compensated for the calibrated position.

Essentially, for a given mechanical position, the angular

measurement system is electrically rotated (by changing

the Zero Position value in the OTP register), until the

output matches the desired mechanical position.

The example in Figure 13 below shows a configuration

for 5V supply voltage and 10%-90% output voltage

range. It adjusted by Zero Position Programming to

provide an analog output voltage of 2.0 Volts at an angle

of 180°. The slope of the curve may be further adjusted

by changing the gain of the OPAMP output stage and by

selecting the desired angular range (360°/180°/90°/45°).

Figure 13: Zero position programming (shown for 360° mode)

VDD5V

0°

90°

180°

270°

360°

analog

output

voltage

mechanical

angle

5V

2V

the output can be electrically rotated to

match

a given output voltage to any

mechanical position

0V