I got a problem with some iPhone 4 vibration motors. I ordered four of them at ebay and connected them like shown at the Arduino page. And the connection is definitely done the right way.
But they make me crazy. At the beginning they work sometimes fine but after a few seconds or after moving them (movement will be needed for our project) they stop or work stagnant. We already ordered two different kinds but non of them works quite fine.
Can someone help me or give me an advise which motors are both compatibel to Arduino and powerful as much as possible (you need to feel them quite well on your skin)? That would be so great!
In the text you can find that it's the same for vibration motors. So do you think I need a transistor in between? What am I doing wrong? We've also shown it to our lecturer and he said it's okay.
Which page (and it better show a transistor or other driver/buffer in there somewhere)...?
The first ones were ordered at ebay. We thought it's maybe a bad quality but the second vibration motors were ordered at watterott a quite good electronic store in germany.
NO! You cannot drive a DC motor direct from an Arduino pin.... These motors may take 60mA or more on startup at their rated voltage of 1.8 or 3V... So at 5V that's more likely to be 100mA at start-up. The intermitant behaviour will probably be the Arduino pin output transistors burning up.
You must drive motors via a suitably rated transistor or MOSFET and must use a backwards diode across the motor to prevent inductive voltage spikes from destroying the circuit.
Arduino pin absolute maximum current for a pin 40mA - 80mA is too large, but also the motor may burn out if over-voltage itself. Run it at its rated voltage using a driving circuit that can deliver the goods, not from a logic signal.
