Data Sheet

MLX90614 family
Single and Dual Zone
Infra Red Thermometer in TO-39
3901090614 Page 41 of 52 Data Sheet
Rev 008 February 28, 2013
The MLX90614 can be configured in EEPROM to operate as a thermal relay. A non contact freezing or
boiling prevention with 1 mA quiescent current can be built with two components only – the MLX90614 and a
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.
2.2uF
1
Vdd
Vss
PW M
SDA
U1
5.7V
C*
+12V
J1
CON1
PWM
V+
GND
3
Equivalent schematics
Q1
Q1
U1
MLX90614
2
C1
SCL
Vz
MLX90614Axx: V=8...16V
+5V
4
R1
R1
Figure 40: 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).