netduino Motor not working via transistor


Posted on Feb 5, 2014

When the motor is connected in this fashion, the netduino activates the transistor, but nothing happens. If i swap the motor with an LED, the LED does light up, so that incidates that the motor isnt getting enough power. So i connect the motor direct to power and gnd, and it spins. Does this mean that the transistor is drawing so much current that


netduino Motor not working via transistor
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it is stopping the motor working Also, I don`t see why the 100ohm resistor is there - it would be better if it were connected between netduino and base of the transistor. pjc50 Apr 27 `13 at 17:29 Updated schematic. Removed unnessecary resistor, and even tried replacing the transistor with a darlinton pair, but in this case there was even less power, as a LED shows even less brightness in place of the motor. Wayneio Apr 27 `13 at 17:48 I believe the netduino IO to be 3V3 and this means the emitter of the transistor can never be higher than about 2. 7V with any load connected. This is realistically the problem you have - the motor is only receiving about half of the 5V it needs and is therefore stalling. The led works because it only needs a couple of volts (more than likely). You need to have the motor and diode (same way round as drawing shows) from the collector up to +5V. The emitter needs grounding and the input to the base (from the netduino) goes via a 1k resistor. Okay, that makes sense. I have swapped the motor and diode to the collector side of the transistor, but am still not seeing the motor move. Could it just be that the output from the netduino IO is not enough Wayneio Apr 27 `13 at 18:17 Have you used a 1kohm resistor in the base As a quick test if you disconnect the resistor from the IO pin and link that point up to +5V does the motor turn If yes, then maybe you haven`t programmed the IO pin correctly. If...




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