MLX90614 family
Single and Dual Zone
Infra Red Thermometer in TO-39
capacitor. The PWM/SDA pin can be programmed as a push-pull or open drain NMOS, which can trigger an
external device, such as a relay (refer to electrical specifications for load capability), buzzer, RF transmitter or
a LED. This feature allows very simple thermostats to be built without the need of any MCU and zero design
overhead required for firmware development. In conjunction with a MCU, this function can operate as a
system alert that wakes up the MCU. Both object temperature and sensor die temperature can also be read
in this configuration.
11.5 High voltage source operation
As a standard, the module MLX90614Axx works with a supply voltage of 5Volt. In addition, thanks to the
integrated internal reference regulator available at pin SCL/Vz, this module can easily be powered from
higher voltage source (like VDD=8…16V). Only a few external components as depicted in the diagram below
are required to achieve this.
R1
Q1
C*
Q1
+12V
+5V
J1
R1
1
MLX90614
SCL
Vz
U1
V+
PWM
SDA
4
Vss
PWM
GND
2
U1
5.7V
Vdd
3
C1
CON1
2.2uF
Equivalent schematics
Figure 27: 12V regulator implementation
With the second (synthesized Zener diode) function of the SCL/Vz pin used, the 2-wire interface function is
available only if the voltage regulator is overdriven (5V regulated power is forced to Vdd pin).
3901090614
Rev 003
Page 32 of 40
Data Sheet
03/Oct/2007
MELEXIS [ Melexis Microelectronic Systems ]
