How to convert 5 volts to 12 volts for a USB Motor

[Summit07]

Hi everyone,
What I am wondering is if there is a way to convert 5 volts to 12 volts. The application I will be using this for is a USB driven motor. The USB cable can only handle 5 volts and the motor is 12 volts. So I am wondering if there is a device or something simple to build that can bridge the gap between the voltages. Thank you for your advice!
Sincerely
Chris

 

[mgb_phys]

Look up dc-dc converter (or boost converter)
But remember that USB can only supply 500mA and the converter will waste some power

 

[brewnog]

Summit, your USB cable isn't limited by voltage, but by current.

 

[russ_watters]

...and therefore it is probably better to find a suitable 5V motor.

 

[Summit07]

Thank you for the advice, much appreciated. Would the same apply if I replaced the USB cable with a Parallel port cable?

 

[brewnog]

Yes the same would apply. The problem is nothing to do with the cable, but your understanding of electrics.

Depending on what you're trying to do (let us know!), I'd go forward with your USB idea with a suitable 5V motor, making sure that you're not going to exceed the relevant current limits.

 

[NoTime]

Unlike USB, which has a designated power connection, Parallel Ports are not designed to provide any power.
Parallel Ports have only signal level outputs.

 

[isly ilwott]

Unlike USB, which has a designated power connection, Parallel Ports are not designed to provide any power.
Parallel Ports have only signal level outputs.

More information is required regarding the motor you are trying to drive. Simply describing it as a 12 volt motor is not sufficient. The kw rating, or horsepower rating, full load current rating is required to determine the power needed to run the motor. Can you describe the motor with more specificity?

I am thinking you may need a separate 12 volt power supply that allows for voltage driven input control.

 

[Summit07]

Thank you again for the advice here are the technical specs of the motor.
HP: 1/10
RPM: 2300
Rotation: Reversible
Torque (oz-in): 40
Field Volts: 12
Diameter: 3in
Shaft Dimension (inches): 5/16 x 2

 

[mgb_phys]

1/10 of a horsepower is 75W
At 12V that is 6.5A, USB can supply 5v at 500ma = 2.5W = 1/300 HP
I think you are slightly out of luck!

You could use a car battery to power the motor and a USB device to control a relay to turn it on/off.

 

[Summit07]

I was crunching the numbers as well and came to that same conclusion. Back to the drawing board it seems...