Do you need an empty ashtray in front of you? Not a problem: every time you put debris in the container, the KEMET’s pyroelectric infrared sensor will trigger the self cleaning process.
The main focus, after you position the sensor, is to try different materials to encapsulate the sensor, until you reach the desired angle and establish a maximum length of the detection.
When the sensor detect the approach of the hand, it generates positive pulses on pin 4.
I noticed that if you lower the Vin of the sensor, there is a different behavior... so in my case, with the help of 2 diodes, I went to the lower limit:
I used a monostable circuit that generate a delay until the motor is turn on. Note that, once triggered, this circuit cannot respond to additional triggering until the timing sequence is complete:
My designed is around the popular standard bipolar 555 IC but, in most cases, will work equally well (or better) with a 7555 or similar CMOS version of the timer IC.
The final result: