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AS5140H

Data Sheet - D e t a i l e d D e s c r i p t i o n

7.12.6 Temperature

sensitive to temperature. While linear Hall sensors require a compensation of the magnet’s temperature coefficient, the AS5140H automatically

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

AS5140H 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 +150º = 190K. The magnetic field change is: 190 x -0.12% = -22.8%, which corresponds to 75mT at -40ºC and 57.9mT at 150ºC.

In the above described scenario, the AS5140H can automatically compensate for the change in temperature related field strength. No user

adjustment is required.

temperature, it may increase 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 (see Internal Timing Tolerance on page 30).