MLX90313KDF ETC [List of Unclassifed Manufacturers], MLX90313KDF Datasheet - Page 31

• Manufacturer Part Number: MLX90313KDF
• Description: Programmable IR Sensor Interface
• Manufacturer: ETC [List of Unclassifed Manufacturers]

Applications Information
In the above application diagram, a simple thermometer with alarm function is depicted. As external
components there are only a thermopile (like the MLX90247x) and a current setting resistor is used.
Because the current needs to be constant over temperature and time, it is advised to use a precision
resistor. The tempout pin is the output of a comparator which compares the measured object temperature
with the threshold set by the external potentiometer. The second comparator operates the relay. It
compares the ambient temperature with a fixed threshold programmed in eeprom. Both ambient and
object temperatures can be read continously by the microprocessor using the SPI interface.
For more application examples, take a look at our MLX90601 Infrared thermometer module, which
incorporates a MLX90247 thermopile sensor and the MLX90313 IR sensor interface.
MLX90313 Programmable IR sensor Interface
3901090313
MLX9024
7
Thermisto
IR sensor
r
high prec.
Rbias
100k
IR+
IR-
Rsens
VSS
10u
AGND
IRINP
IRINN
CREF
TINP
TINN
VDD
VSS
Typical application diagram
OPA
OPA
Control and Support Blocks
Page 31
A/D
A/D D/A
Digital
D/A
Ta
Programmable IR Sensor Interface
12
To
Ta
COMP
12
MLX90313
COMP
SPI
IROUT
TEMPOUT
VREFP
VDD1
REL1
Micro-controller I/O-port
MLX90313
Rev 1.0 21-July-2001
SW1
SW2
Vref