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AS5045B

Datasheet - Application In form atio n

ulation (PWM) Output on page 15)

9.6.6 Temperature

sensitive to temperature. While linear Hall sensors require a compensation of the magnet’s temperature coefficients, the AS5045B automatically

compensates for the varying magnetic field strength over temperature. The magnet’s temperature drift does not need to be considered, as the

AS5045B operates with magnetic field strengths from ±45…±75mT.

Example: A NdFeB magnet has a field strength of 75mT @ –40ºC and a temperature coefficient of -0.12% per Kelvin. The temperature change

is from -40º to +125º = 165K.The magnetic field change is: 165 x -0.12% = -19.8%, which corresponds to 75mT at -40ºC and 60mT at 125ºC.

The AS5045B can compensate for this temperature related field strength change automatically, no user adjustment is required.

9.6.7 Accuracy over Temperature

The influence of temperature in the absolute accuracy is very low. While the accuracy is less than or equal to ±0.5º at room temperature, it can

increase to less than or equal to ±0.9º due to increasing noise at high temperatures.

to ±10%. Generally, the timing tolerance has no influence in the accuracy or resolution of the system, as it is used mainly for internal clock

generation.

The only concern to the user is the width of the PWM output pulse, which relates directly to the timing tolerance of the internal oscillator. This

influence however can be cancelled by measuring the complete PWM duty cycle instead of just the PWM pulse.