AS5030 8-bit Programmable Magnetic Rotary Encoder

Rev. 1.8

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Page 17 of 33

5.2.4

18-bit OTP Write Commands

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

Command

Bin

Hex

D17

D16

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

WRITE

OTP

11111

1F

copy factory settings

obtained from READ OTP command

sens

1:0

zero position

7:0

PROG

OTP

11001

19

00000000

reserved for factory settings,

sens

1:0

zero position

7:0

WRITE OTP:

non-permanent (“soft write”) modification of the OTP register. To set the reserved factory settings area

properly, a preceding READ OTP command must be made to receive the correct setting for bits D17:D10.

The WRITE OTP command must then set these bits in exactly the same way. Improper setting of the factory

settings by a WRITE OTP command may cause malfunction of the chip. The OTP register, including the

factory settings can be restored to default by a power-up cycle.

For non-permanent writing, a programming voltage at pin PROG (#2) is not required.

PROG OTP:

permanent modification of the OTP register. An unprogrammed OTP bit contains a ‘0, programmed bits are

1’s. It is possible to program the OTP in several sequences. However, only a 0 can be programmed to 1.

Once programmed, an OTP bit cannot be set back to 0. For subsequent programming, bits that are already

programmed should be set to 0 to avoid double programming.

During permanent programming, the factory settings D17:D10 should always be set to zero to avoid

modification of the factory settings.

Modifying the factory settings may cause irreversible malfunction of the chip.

For permanent programming, a static programming voltage of 8.0-8.5V must be applied at pin PROG (#2)

sens

sets the sensitivity setting of the Hall elements :

00: gain factor = 1.65 (low sensitivity)

01: gain factor = 1.75

10: gain factor = 1.86

11: gain factor = 2.00 (high sensitivity)

zero position

sets the user programmable zero position; the actual angle of the magnet which is displayed as 000

Figure 21: Timing diagram in OTP 18bit read/write mode

5.3

OTP Programming Connection

Programming of the AS5030 OTP memory does not require a

dedicated programming hardware. The programming can be

simply accomplished over the serial 3-wire interface (shown in

Figure 22) or the optional 2-wire interface (shown in Figure 8).

constant DC voltage of 8.0V ~ 8.5V (≥100mA) must be

connected to pin #2 (PROG).

For temporary OTP write (“soft write”; command WRITE OTP,

To secure unintentional programming, any modification of the

OTP memory is only enabled after a special password (command

Figure 22: OTP programming connection

AS5030

Micro

Controller

100n

CS

CLK

DIO

+5V

VDD

VSS

VSS

C2

VDD

VDD

13

11

10

12

15

C1

VSS

3

14

I/O

Output

Output

8.0 – 8.5V

PROG

2

10µF 100n