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Does a breadboard supply the same amount of power to everything connected

Rushmoore

Jun 21, 2015
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I have a 9v battery hooked up to 2 joysticks which need about 4v each. I have the power wires connected to the breadboard positive strip which is connected to the 9v battery's positive terminal and both ground wires connected to the breadboard negative strip which is connected to the negative battery terminal. Will the joysticks receive the full 9v (like in a parallel circuit) or will the volts be split between the joysticks?

Thanks :)
 

Martaine2005

May 12, 2015
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Hi Rushmore,
They will both get 9v. As in parallel.
You will need to supply them 4v.
Instead of the pp3 9v battery, use 3 AA batteries for about 4.5v with new cells.

You could also use either side of the breadboard power rails and power them individually.

Martin
 

Rushmoore

Jun 21, 2015
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Hi,

Thank you very much for your reply. I have two servos using a similar circuit. They are both hooked up to a 9v battery on the breadboard, their operating voltage is about 4.8v, if they are both getting 9v why don't they blow up?

Thanks,

Rushmoore
 

Martaine2005

May 12, 2015
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Maybe they have a wide voltage range. Or depending on the servo, the motor is more forgiving.
If it's pwm, they can handle more because it's pulsed.
Try that same servo on 4v. It may be slower than on 9v. Or you are just lucky?

It's not really good practice to hook something up to a higher voltage unless you want to blow it up!!.
Better to try and use the voltage it was designed for.
There are many things that will work on higher voltages, but for how long is the question. The components might be slowly cooking.

Martin
 

Rushmoore

Jun 21, 2015
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Are resistors for servos a bad idea? How would you work out what resistor is needed if you had a 9v battery and a servo that draws about 4.8v?
 

Martaine2005

May 12, 2015
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You could do that. But resistors are current limiting.
You would need to know current used by the devices. But I would assume a servo or joy sticks current draw would change as they are moved.
A voltage divider maybe better here. Or a 5v regulator.

Martin
 

BobK

Jan 5, 2010
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You could do that. But resistors are current limiting.
You would need to know current used by the devices. But I would assume a servo or joy sticks current draw would change as they are moved.
A voltage divider maybe better here. Or a 5v regulator.

Martin
Yes, you could do that, but it would not supply the correct voltage to the servo. Using a resistor to reduce voltage will work only if the device draws the same amount of current always, like an LED. A servo will draw much more current when the motor is running than when it is stopped. So, if you size the resistor to supply the correct voltage when the motor is running, it will see nearly 9V when the motor is not running.

Bob
 
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