AS5171 datasheet(12/42 Pages) AMSCO

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ams Datasheet

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[v1-01] 2016-Feb-17

AS5171 − Detailed Description

The AS5171 is a Hall-based rotary magnetic position sensor

using a CMOS technology. The lateral Hall sensor array converts

the magnetic field component perpendicular to the surface of

the chip into a voltage.

The signals coming from the Hall sensors are first amplified and

filtered before being converted by the analog-to-digital

converter (ADC). The output of the ADC is processed by the

CORDIC block (Coordinate-Rotation Digital Computer) to

compute the angule and magnitude of the magnetic field

vector. The sensor and analog front-end (AFE) section works in

a closed loop alongside an AGC to compensate for temperature

and magnetic field variations. The calculated magnetic field

strength (MAG), the automatic gain control (AGC) and the angle

can be read through the output pin (OUT) in UART mode.

The magnetic field coordinates provided by the CORDIC block

are fed to a digital filter which reduces noise. A linearization

block generates the transfer function, including linearization.

The AS5171 is available with two different output interfaces:

analog ratiometric (AS5171A) or digital PWM (AS5171B).

The output of the AS5171 can be programmed to define a

starting position (zero angle) and a stop position (maximum

angle). An embedded linearization algorithm allows reducing

the system INL error due, for example, to mechanical

misalignment, magnet imperfections, etc.

The AS5171 can be programmed through the OUTpin with a

UART interface which allows writing an on-chip non-volatile

memory (OTP) where the specific settings are stored. The

AS5171 can be programmed by the ams programming tool,

both at the component and board level.

Detailed Description

AS5171 Datasheet(PDF) 12 Page - ams AG