MLX90247 Datasheet, PDF (2/11 Pages) List of Unclassifed Manufacturers – Discrete Infrared Thermopile Detectors

40uV/K
60kOhm
Thermopile
1
OutIr+
3
OutIr-
2
Rsens
26kOhm _{ϑ +}
PTC
4
VSS
Socket
MLX90247DSA
2. Description
The MLX90247family sensors are thermopile
sensors IC which detects very small amounts of
heat radiation. The sensors consist of a
membrane with a thermopile on top of it.
The hot junctions of the thermopile are
positioned near the center of the membrane and
the cold junctions above the bulk silicon edge.
Due to the low thermal conductivity of the
membrane, absorbed heat will cause the
temperature to increase more at the center of
the membrane than at the edge above the bulk.
This temperature difference is converted to an
electric potential by the thermo-electric effect in
the thermopile junctions. No supply voltage is
needed.
sensor and thermistor can be used independent
of each other if desired, as the thermopile
potential is floating. This type of thermistor has
better sensitivity than the PTC types, but must
be used in smaller ambient ranges. Typical
applications are ear thermometers or other
medical equipment.
The MLX90247DSA sensor IC is integrated
together with a PTC thermistor. The sensor and
thermistor can be used independent of each
other if desired, as the thermopile potential is
floating.
The MLX90247DSG sensor IC is integrated
together with a PTC thermistor. The thermopile
sensor is grounded at the middle point, so that
the output common-mode voltage is at ground
potential. Using grounded thermopile sensor
gives improved EMC susceptibility in some
applications.
The MLX90247DSE sensor IC is packaged
together with a 100k NTC chip thermistor. The
3901090247
Rev. 002
Page 2-2 of 11
Data Sheet
Aug/02