AS5261

Datasheet - Application In form atio n

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9.7 Programming Procedure

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Pull-up on out pin

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VDD=5V

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Wait 10ms (after the startup time device enters communication mode)

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Write command: Trimming bits are written in the OTP RAM

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Read command: All the trimming bits are read back to check the correctness of the writing procedure.

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Write AS5261KEY in the Fuse register: The OTP RAM content is permanently transferred into the Poly Fuse cells.

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Wait 10 ms (fuse time)

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Write command, R1K_10K<1:0>=(11)b: Poly Fuse cells are downloaded into the RAM memory using a 10K resistance as reference.

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Wait 5 ms (download time)

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Read R1K_10K register, the expected value is 00b

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Write command, R1K_10K<1:0>=(11)b

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Read R1K_10K register, the expected value is (11)b. NB: Step11 and Step12 have to be consecutive.

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Read command: all the fused bits downloaded with 10K resistance are read back.

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Write command, R1K_10K=<1:0>=(10)b: Poly Fuse cells are downloaded into the RAM memory using a 1K resistance as reference.

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Wait 5 ms (download time)

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Read R1K_10K register, the expected value is (00)b

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Write command register, R1K_10K<1:0>=(10)b

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Read R1K_10K register, the expected value is (10)b NB: Step18 and Step19 have to be consecutive.

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Read command: All the fused bits downloaded with 1K resistance are read back.

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Check that read commands at Steps 5, 13 and 19 are matching

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Write AS5261 KEY in the Pass2Func register: Device enters normal mode.