MLX90320_12 Datasheet, PDF (10/33 Pages) Melexis Microelectronic Systems – Automotive sensor interface

6 Detailed Description
MLX90320
Automotive sensor interface
Figure 1: General block diagram of the MLX90320
The MLX90320 can be used with almost any type of resistive bridge sensor without the need of any additional
signal conditioning.
The differential input signal is offset compensated and amplified to achieve the desired output voltage. With a
coarse gain calibration the MLX90320 can easily accommodate sensor output spans in the 1.8mV/V to 63mV/V
range to achieve 4 V output span. Sensor output offsets until 97.2mV/V (depending on the sensor output span
and on the desired output offset, see table 3 for the details) can be compensated with the coarse offset
calibration to achieve an output offset in the 0.5V to 4.5V range. Figure 2 shows two typical output characteristics
that can be obtained with the MLX90320. The option of swapping the inputs by setting one bit in EEPROM and
the wide variation of the output offset with the coarse offset calibration allows calibrating a decreasing output
characteristic as shown in figure 2. All output characteristics between those described in figure 2 can be achieved
for a wide range of sensor output spans and offsets.
3901090320
Rev 007
Page 10 of 33
Data Sheet
Feb/12