PIR Sensor troubleshooting
I'm an electronics newb, hoping someone can help me.
I'm trying to trigger a 1.5-3 volt DC motor using a PIR sensor, without using a microcontroller.
I have the PIR sensor's output connected to an npn transmitter which triggers a 5v spdt relay to switch on the motor. When testing the circuit with an LED, it works perfectly, turning the LED on when motion is detected.
When I swap the LED for the motor, the relay turns on the motor repeatedly every 6 seconds no matter whether there is motion or not.
(it also may have killed the relay after about a minute or two)
I tried a different circuit, using a transistor as a switch instead of a relay, which also works perfectly with an LED, but when the motor is connected instead, again the motor is turned on every 6 seconds without a care for the PIR output.
What could I be doing wrong here? I'm assuming that perhaps it has something to do with kickback from the motor...maybe?
Anybody have any advice? (Remember, no microcontroller! As much as I'd love to try my hand at using arduino or the like, I can't afford to use a microcontroller for this particular project.)