AS5261

Datasheet - Application In form atio n

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Revision 1.1

15 - 32

9 Application Information

9.1 Recommended Application Schematic

Figure 10 shows the recommended schematic in the application. All components marked with (*) are optional and can be used to further

increase the EMC.

Figure 10. AS5261 6-Wire Connection with Pull-Up Resistors

9.2 Programming the AS5261

The AS5261 programming is a one-time-programming (OTP) method, based on polysilicon fuses. The advantage of this method is that no

additional programming voltage is needed. The internal LDO provides the current for programming.

The OTP consists of 128 bits; several bits are available for user programming. In addition factory settings are stored in the OTP memory. Both

regions are independently lockable by build in lock bits.

A single OTP cell can be programmed only once. Per default, the cell is “0”; a programmed cell will contain a “1”. While it is not possible to reset

a programmed bit from “1” to “0”, multiple OTP writes are possible, as long as only unprogrammed “0”-bits are programmed to “1”.

Independent of the OTP programming, it is possible to overwrite the OTP register temporarily with an OTP write command. This is possible only

if the user lock bit is not programmed.

Table 10. External Components

Symbol

Parameter

Min

Typ

Max

Unit

Note

VDD buffer capacitor

0.8

1

1.2

µF

Low ESR 0.3

Ω

VDD3V3 regulator capacitor

0.8

1

1.2

µF

Low ESR 0.3

Ω

OUT load capacitor (sensor PCB)

0

4.7

nF

*

VDD capacitor (optional)

4.7

nF

Do not increase due to

programming over output.

*

VDD serial resistor (optional)

10

Ω

OUT load capacitor (ECU)

0

33

nF

*

OUT serial resistor (optional)

50

Ω

OUT pull-up resistance

4

10

k

Ω

Electric Control Unit

TP1_T

TP1_B

16

13

14

15

5

8

7

6

1

4

3

2

12

9

10

11

S_B

S_T

TP3_B

TP3_T

AS5261

VDD3V3_T

VDD3V3_B

Sensor PCB

VDD1

VDD2

GND1

GND2

OUT2

OUT1