IAQ Air Quality Sensor + Arduino ProMini + I2C

Update 03.04.2018: It looks like you can buy a newer better chip with 3.3V here: link

For my first Helike® Robot I needed an Air Quality Sensor and I’ve found one: IAQ Engine in form of an USB component: YOCTO-VOC . This is a VOC Air Sensor. The YOCTO-VOC has an USB connection only, so I’ve disassabled the VOC Sensor to connect the sensor  via the I2C interface  (IAQ document). Because all of my sensors are using the I2C interface. 20150605_182506 But be careful, it’s not allowed to send (write) commands to the IAQ Sensor, because this will change the I2C address from 0x5A to 0x40 …and after the 3rd try to write some data… the IAQ Sensor is dead, like mine. This is the reason why I’ve ordered again two pieces. With the 2nd sensor I’ve did the same mistake, because any written byte on the I2C bus, also its a different I2C address, will destroy the IAQ Sensor! So what is now to do? To isolate the whole IAQ Sensor and still using the I2C interface, is to use an Arduino ProMini 5V/16Mhz Board and the analog output value of the IAQ Sensor (Pin 1). Then I’ve connected the I2C Arduino Pro Mini Pins with my Robot. I’ve soldered the IAQ sensor on the Arduino Pro Mini (IAQ Sensor Pin 1 => Arduino Analog A0)  and I’ve used the I2C Connector “5V” as Input Voltage for the Arduino “RAW In” Pin and IAQ Sensor “5V” Pin 6. Voila, I’ve uploaded the Arduino Sketch, connected the I2C 4 wire connector to my robot… and can request the IAQ Sensor value (450-2000 ppm).

VOC_Arduino_Circuit_diagram

20150606_000119

Download: <In order to finance everything that belongs to it, the downloads will be activated after a donation>

Thanks for your support!