MLX90247_04

MLX90247 family Discrete Infrared Thermopile Detectors Features and Benefits Solid state thermopile sensor On-chip thermistor for ambient temperature compensation High reliability and long-term stability Very high ESD protection – 7 kV on all pins (only for MLX90247BAA and MLX90247BAL) Low cost, small size Ordering Information Part No MLX90247 MLX90247 MLX90247 MLX90247 Ta Suffix Package code SF(TO-39) SF(TO-39) SF(TO-39) SF(TO-39) Type Description Large aperture (3.5mm) thermopile detector with on-chip PTC DSA thermistor, floating thermopile outputs. Small aperture (2.5mm) thermopile detector with on-chip PTC DSL thermistor, floating thermopile outputs. Large aperture (3.5mm) thermopile detector with on-chip PTC BAA thermistor, floating thermopile outputs. Excellent ESD Small aperture (2.5mm) thermopile detector with on-chip PTC BAL thermistor, floating thermopile outputs. Excellent ESD E (-40C to +85C) E (-40C to +85C) E (-40C to +85C) E (-40C to +85C) Notice: In case sensor is used in automotive applications, Melexis must be informed. Applications Automotive contactless temperature sensing. IR thermometers Gas analysis equipment Occupancy detection 1. Functional Diagram 2. Description At the heart of the MLX90247 thermopile sensors is a silicon die with a central micromachined membrane surrounded by a bulk silicon edge. The hot junctions of the thermopile are positioned near the center of the membrane and the cold junctions are located above the bulk silicon edge. Infrared irradiation of the low thermal conductivity membrane creates a temperature difference between the membrane and the surrounding bulk silicon. The resulting thermopile voltage is a function of the temperature difference between the object and the sensor. Measurement of the absolute temperature of the object is possible by relating the thermopile signal to the temperature of the sensor. The exact temperature of the sensor is measured by a PTC thermistor integrated in the bulk silicon edge. No supply voltage is needed for the thermopile. The sensor and thermistor can be used independently of each other if desired, as the thermopile potential is floating. The MLX90247DSL (BAL) sensor IC is similar to MLX90247DSA (BAA) but with smaller aperture, thus resulting in narrower field of view (FOV). 60 kOhm 1 Out IR+ 40 uV/K 3 Out IRThermopile 2 Rsense 24 kOhm PTC Socket 4 VSS 3901090247 Rev. 003 Page 1 of 10 Data Sheet Jun/04 MLX90247 family Discrete Infrared Thermopile Detectors Table of contents 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. FUNCTIONAL DIAGRAM ............................................................................................................. 1 DESCRIPTION............................................................................................................................... 1 GLOSSARY OF TERMS ............................................................................................................... 3 PIN DEFINITIONS AND DESCRIPTIONS .................................................................................... 3 MLX90247 SPECIFICATIONS ...................................................................................................... 3 UNIQUE FEATURES..................................................................................................................... 5 APPLICATIONS INFORMATION.................................................................................................. 6 RELIABILITY INFORMATION ...................................................................................................... 7 ESD PRECAUTIONS .................................................................................................................... 7 PACKAGE INFORMATION........................................................................................................... 8 DISCLAIMER............................................................................................................................... 10 3901090247 Rev. 003 Page 2 of 10 Data Sheet Jun/04 MLX90247 family Discrete Infrared Thermopile Detectors 3. Glossary of Terms IR: Infrared. Every object emits infrared radiation in relation to its temperature. This effect can be used to measure the temperature without the need for physical contact. PTC: On-chip thermistor which resistance increases with rising temperature (Positive Thermal Coefficient) 4. Pin Definitions and Descriptions TO-39 package - connections 1 Pin 1 2 4 Symbol OutIr+ Rsens OutIrVss Description Infrared Thermopile positive output Thermistor for sensor ambient temperature measurement Infrared Thermopile negative output Thermistor ground / case potential 2 3 4 3 Top view = pins down 5. MLX90247 Specifications Operating temperature range: Ta = -40 to 125 ˚C unless otherwise noted Parameter Sensitive Area DC membrane responsitivity Sensitivity Window aperture size Field of view Spectral sensitivity Thermopile Resistance Noise 3901090247 Rev. 003 Type All All DSA and BAA DSL and BAL DSA and BAA DSL and BAL DSA and BAA DSL and BAL All All All Typical 1.2 x 1.2 12 46 34 ±25% ±25% Units mm2 V/W µV/˚C µV/˚C mm mm deg deg % % kΩ nV / √Hz Condition Tbb = 25˚C Full FOV Full FOV 3.5 2.5 100 85 > 70