3V DC Micro Vibration Motor and Arduino Uno

Other Hardware Motors, Mechanics, Power and CNC
1

Newbie Question-

I know the Arduino Uno can output either 3.3 or 5 Volts.

I have a 3.3V DC Micro Vibration Motor that I want to turn on when a button is pushed.

Is it necessary to step-down the voltage output by the Arduino from 3.3v to 3v? And if so, how can I do that?

THANKS!

2

Uno outputs 5V, and current limited to 30 / 40 mA only. To drive a 3V motor, you should use a simple circuit with one transistor and diode.

motor.png
motor.png800×600 9.68 KB

3

Hi, Where will the 3.3V come from? Arduino has a 3.3V output but with little current available.

How much current does the motor draw??

4

@Magician- Thank you so much for the diagram. I'm still trying to find out how to read those diagrams and what the symbols mean, I'll research that online.

@Terry- The current is 95mA. Maybe the motor won't work at all, or just slower than normal.

Thanks!!!

5

OK, the Arduino 3.3V Output:
3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.

So, How about using the 5V supply.

You need a switching transistor. An NPN with Emitter to ground, Base to Arduino output through 470 ohm resistor, collector to motor through A RESISTOR, other motor connection to +5.

So you have the motor (should be 3.3V) at 95 ma (0.095 amps) and a 5.0V supply.
So you need to "lose" 5.0V - 3.3V = 1.7 volts
You calculate the resistor as R=E/I or R= 1.7/0.095 = 16 ohms. So, find a standard value, like 15 ohms.
How much power must the resistor dissipate? P=EI = 1.7.095 = .16 watts. so a 1/4 watt resistor would be OK.

Let us know if it works!