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AS5311

Datasheet - D e t a il e d D es c r i pt io n

7.1 Incremental Outputs

Figure 4 shows the two-channel quadrature output of the AS5311. Output A leads output B when the magnet is moving from right to left and

output B leads output A when the magnet is moving from left to right(see Figure 14).

Figure 4. Incremental Outputs

7.1.1 Incremental Power-up Lock Option

After power-up, the incremental outputs can optionally be locked or unlocked, depending on the status of the CSn pin:

incremental outputs A, B and Index will be high until the internal offset compensation is finished. This unique state may be used as an indicator

for the external controller to shorten the waiting time at power-up. Instead of waiting for the specified maximum power up-time (see Electrical

System Specifications on page 8), the controller can start requesting data from the AS5311 as soon as the state (A= B= Index = high) is cleared.

CSn goes low or a low pulse is applied at CSn and internal offset compensation is finished. This mode allows intentional disabling of the

incremental outputs after power-up until for example the system microcontroller is ready to receive data.

Once the incremental outputs are unlocked they can not be disabled during operation.

Movement left to right

A

B

Incremental outputs

Index=0

1LSB

Index

Mechanical

Zero Position

Movement Direction

Change

CSn

Hyst =

2 LSB

Movement right to left

Mechanical

Zero Position