AS5030 8-bit Programmable Magnetic Rotary Encoder

Rev. 1.8

www.austriamicrosystems.com

Page 16 of 33

5.2

AS5030 Read / Write Commands

Data transmission with the AS5030 is handled over the 2-wire or 3-wire interface. The transmission protocol begins with sending

a 5-bit command to the AS5030, followed by reading or writing 16 or 18 bits of data:

5.2.1

16-bit Read Command

Command

Bin

Hex

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

RD

ANGLE

00000

00

C2

lock

AGC 5:0

Angle 7:0

C2

displays status of hardware pin C2 (pin #15)

Lock

indicates that the AGC is locked. Data is invalid when this bit is 0

AGC

6-bit AGC register. Indicates the strength of the magnet (e.g. for pushbutton applications)

ideally, the vertical distance of the magnet should be chosen such that the AGC value is in the middle (around

100000b)

Angle

8-bit Angle value; represents the rotation angle of the magnet. One step = 360°/256 = 1.4°

5.2.2

16-bit Write Command

These settings are temporary; they cannot be programmed permanently. The settings will be lost when the power supply is

removed.

Command

Bin

Hex

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

EN PROG

10000

10

1

0

0

0

1

1

0

0

1

0

1

0

1

1

1

0

SET PWR

MODE

10001

11

ULP/

LPn

PSM

0

DIS HYST

10011

13

HYS

0

DIS AGC

10101

15

0

0

0

0

0

rst

0

0

0

AGC 5:0

FA

EN PROG

ULP/LPn

selects the Ultra Low Power Mode, when bit PSM is set: 0 = Low Power Mode, 1 = Ultra Low Power Mode

PSM

enables power saving modes: 0 = normal operation, 1 = reduced power mode selected by bit ULP/LPn

HYS

disables the hysteresis of the digital serial and PWM outputs:

0 (default) = 1-bit hysteresis, 1 = no hysteresis

DIS AGC

disables the automatic gain control. The AGC will be frozen to a gain setting written in bits AGC 5:0 (D6:D1),

bit FA must be set.

rst

General Reset: 0 = normal operation, 1 = perform general reset (required after return from reduced power

modes)

FA

Freeze AGC; 0 = normal operation, 1= freeze AGC with the values stored in bits AGC 5:0. The PWM output

will be invalid when bit FA is set.

5.2.3

18-bit OTP Read Commands

Note: to prohibit unintentional access to the OTP register, OTP PROG/write access is only enabled after the EN PROG

command (see 5.2.2) has been sent. OTP access is locked again by sending a RD ANGLE or SET PWR MODE command.

EN PROG has not to be sent before a READ OTP.

During the 18bit OTP read/write transfer, each bit needs 4 clock pulses to be validated.

Command

Bin

D16

D15

D14

D13

D12 D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

READ

OTP

01111

0F

reserved for factory settings

sens

1:0

zero position

7:0

ANALOG

OTP RD

01001

09

reserved for factory settings

sens

1:0

zero position

7:0

READ OTP

reads the contents of the OTP register in digital form. The reserved area may contain any value

ANALOG OTP RD reads the contents of the OTP register as an analog voltage at pin PROG (see 5.4)

sens

reads the sensitivity setting of the Hall elements : 00 = high sensitivity, 11 = low sensitivity

zero position

reads the programmed zero position; the actual angle of the magnet which is displayed as 000