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AS5311

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

7 Detailed Description

The different types of outputs relative to the magnet position are outlined in Figure 3 below.

The absolute serial output counts from 0….4095 within one pole pair and repeats with each subsequent pole pair.

Likewise, the PWM output starts with a pulse width of 1µs, increases the pulse width with every step of 0.488µm and reaches a maximum pulse

width of 4097µs at the end of each pole pair.

An index pulse is generated once for every pole pair.

256 incremental pulses are generated at each output A and B for every pole pair. The outputs A and B are phase shifted by 90 electrical degrees,

which results in 1024 edges per pole pair. As the incremental outputs are also repeated with every pole pair, a constant train of pulses is

generated as the magnet moves over the chip.

Figure 3. AS5311 Outputs Relative to Magnet Position

S N S

N

S

N

S N S

N

S

N

0 … .. 4095 0 … .. 4095 0 … .. 4095 0 … .. 4095

absolute output : 0 … .. 4095

0 … .. 4095

Index : 1 pulse / polepair

A : 256 pulses / polepair

B : 256 pulses / polepair

A + B = 1024 steps / polepair

2mm

PWM output : 1 … . 4097µs