MLX90215_12 Datasheet, PDF (5/14 Pages) Melexis Microelectronic Systems – Position Programmable Linear Hall Effect Sensor

MLX90215
Position Programmable
Linear Hall Effect Sensor
Temperature Compensation
Temperature compensation (TC) is defined as thechange in sensitivity over temperature. Expressed in
(Parts Per Million per Degree Celcius) ppm/oC.
SensT1 = Sensitivity measured at Temperature 1 (T1)
SensT2 = Sensitivity measured at Temperature 2 (T2)
Sens25 = Initial Sensitivity measured at 25oC
Programming the Temperature Compensation
The MLX90215 has a 5-bit (32 step) programmable adjustment that changes it’s sensitivity drift over a given
temperature range. By adjusting the TC code the sensitivity can be programmed to increase as
temperature increases to counteract the decrease in magnetic flux most magnets display over temperature.
For example a SmCo (Samarium Cobalt) magnet has a temperature coefficient of approximately -300 ppm/oC.
The MLX90215 can be programmed with a TC of 300 ppm/oC to counteract the TC of the magnet and greatly
improve linearity in the application over temperature.
3901090215
Rev 008
Page 5 of 14
Nov/12