Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Voltage Multiplier

  1. Apr 22, 2004 #1
    I was wondering if anyone know how to take the circuit from a throw away camera and make it increase the voltage in a 1.5V battery. I'm building a car right now and as u probably know 1.5V isn't enough to run it and i'm trying to get it too at least 5v.
  2. jcsd
  3. Apr 22, 2004 #2


    User Avatar
    Science Advisor

    wayne - you need more than just 5V, you need some power (voltage and current) to move a little car.

    the circuit for driving a flash might very well increase the voltage to 100V or more, but it will have only a small amount of current and for a VERY SHORT period of time.

    why not just use a 9V battery or 4 AA batteries?

  4. Apr 23, 2004 #3
    Thanks for responding cliff but it's a project for school and we are only allowed to use a 1.5V batery to: Make the car go up a 10 and 25 degree ramp with a trailer that has wight in it, and have working head lights. All this has to be run off of a 1.5V battery.
  5. Apr 23, 2004 #4


    User Avatar
    Staff Emeritus

    How much weight are we talking about? I think you should be more concerned over the gearing and the weight of the car than trying to double or triple the voltage. The power output is always going to be the same no matter if have a voltage multiplier. Remember P=IV and V=IR. If the resistance is constant and you double the voltage, the current is reduced by the same magnitude. Also when you introduce more circuitry you are going to end up wasting energy in the process. Just stick wih the 1.5V battery and use a 1.5V DC motor. You can get one here (http://scientificsonline.com/product.asp_Q_pn_E_3037590), your local hobby store or radio shack.
  6. Apr 23, 2004 #5


    User Avatar
    Science Advisor

    ^ Agreed.

    LEDs too.

    An o-ring as a belt might be an idea for a low-loss gearing system too.

  7. Apr 23, 2004 #6
    Years ago I used a batery contained in a Polaroid film pack to power a small motor for my son's grade school project; to demonstrate perpetual motion, a scam but he fessed up. Unfortunately I cannot recall its voltage, but I think it was 1 1/2volt. It was about 2" X 3.5", and perhaps 1/32" in thickness. I believe I cut it to size with a scissors, but it's been so long I hardly remember. I used it because it was easy to hide. But it turned out to have a good deal of punch compared to the carbon-zinc battery of the day. I don't know if the energy would be comparable to a modern exotic metal battery, but it may have a greater reactive surface area, lesser internal impedance, and a weight advantage. Might be worth investigating if they're still being made.

    As an aside, I also used the sonic focusing circuitry of a cheap Polariod camera in another of his projects.
    Last edited by a moderator: Apr 23, 2004
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook