MLX90320
Automotive small sensor interface
Features and Benefits
Applications Examples
Suited cost optimized sensors: gain and
offset correction by programmable
coefficients
Higher order temperature compensation
provided for both gain and offset
External or internal temperature sensor
for compensation of temperature errors
Over-voltage protection
Pressure transducers, strain gauges,
accelerometers, position sensors, etc.
Steering systems (e.g. torque sensors)
Safety restraints systems (e.g. seat
occupant detection)
Braking systems (e.g. ABS, force)
Comfort systems (e.g. air conditioning)
Engine management (e.g. injection)
Any bridge type sensor
Fault detection and clamping levels
Ratio-metric output: 0 to 5V
Single Pin Digital Programming
Fully analog signal path
Ordering Information
Part No.
Temperature Code
Package Code
MLX90320LFR
L (-40°C to 150°C)
FR (SSOP 209 mil)
1 Functional diagram
2 General description
The MLX90320 covers the most typical resistive
type of Wheatstone bridge applications for use in an
automotive environment. It is a monolithic silicon
analog integrated sensor interface that converts
small changes in resistors, configured in a full
Wheatstone bridge on a sensing element, to large
output voltage variations.
VDD
7bits
Over- & Reverse
Voltage Protection
POR
Optional clamping
levels and fault
detections
DAC
CSOF
Ratiometric
Chopping
Chopping
Oscillator: 4 MHz (+/-
15%) -> 250kHz dig
+
INM
INP
Gdido
Gdts
-
Gcs
IINV
VDD
DAC
FLT
1
2
10bits
VDD
TMP
Select
Application
mode Output
Programming
mode I/O
10bits
DAC
Fine Offset
=
Fine Gain
+
=
Oo
+
O1.(T-T1) + O2.(T-T1)×
X2.117
X(-1.667)
Go
+
G1.(T-T1) G2.(T-T1)×
Fine Offset
Fine Gain
VDD
The signal conditioning includes gain adjustment,
offset control and second order temperature
compensation in order to accommodate variations of
the different resistive sensing elements.
Go,G1,G2
EEPROM
TMP
T
Oo,O1,O2
T1
TMP
Gain
ALU
ADC
Go,G1,G2,Oo,O1,O2,T1, Gcs,
Gdido, Gdts, IINV, TMP_Select,
TMP_Offset, TMP_Gain,
10bits
TMP
Offset
CSOF, CLKAdj, Clamp_settings
Compensation values are stored in EEPROM and
can be reprogrammed with an interface circuit and a
provided software. The MLX90320 is programmed
with a single wire serial interface through the output
pin.
The user can specify on chip clamping levels thus
creating fault detection bands. By intercepting
various fault modes the MLX90320 is able to inform
about the reliability of its analog output signal.
3901090320
Rev 004
Page 1 of 32
Data Sheet
Mar/05