I looked at 7 low-cost air quality sensors using the setup described below. Most of these require a 48hour preheating period, so I kept them on for a few days before testing the output. You can check out what the preliminary sensor output looks like in several different locations.
I ordered a 6-pin connector (Tyco Part #2058943-5) to avoid the fragile soldering
In the diagram the pins are ardered from left to right as shown in the photograph
The LED pin has to be modulated with a cycle of 1ms as discussed in the datasheet.
The LED seems to use a PNP transistor so to power on, the LED pin must actually recieve a lower voltage.
Sample Arduino code:
digitalWrite(ledPower,LOW); // Power on the LED // ledPower is any digital pin on the arduino connected to Pin 3 on the sensor
dustVal = analogRead(dustPin); // read the dust value via pin 5 on the sensor
digitalWrite(ledPower, HIGH); // turn the LED off