12v to 15 v 7 amp

Discussion in 'General Electronics Chat' started by aac9876, May 8, 2011.

  1. aac9876

    Thread Starter Active Member

    Dec 9, 2006
    where can I find retail a 12v convert to 15 volt 5-8 amp cigarette adaptor
    in the SE USA??? will a 12 volt run a 15v computer,Toshiba??
  2. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    Hard to say. It is not a common item and would probably be expensive. Easiest way to run a computer in the car is with a DC to AC INVERTER. Then you just use your AC adapter like you would in the house with 120VAC outlet. Computer uses small amount of current so anything 200W down to 80-100Watt would work.
  3. Adjuster

    Well-Known Member

    Dec 26, 2010
  4. iONic

    AAC Fanatic!

    Nov 16, 2007
    You need a automotive power inverter that converts 12VDC(Cig. Lighter) to 110VAC, then plug in the laptop to the inverter.
  5. Jaguarjoe

    Active Member

    Apr 7, 2010
    The electrical system in my Ford F150 runs at 14.75 volts while the engine is running. Light load, heavy load, low speed, high speed, it doesn't matter. 14.75 v +/- 10mv. This is so close to 15 that your lap top probably won't know the difference. The challenge now would be filtering out the noise and potential upsets that could cause damage.
    You may want to measure your car and see what you have.
  6. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    It might be a 'close enough' voltage to work, but the voltage spikes and sags and other noise in automotive DC circuits might be the end of your computer in short time. Better off running the AC inverter and letting a power adapter deal with the noise.
  7. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    There are a number of commercial and kit projects that generate 15v or 17v from a 12v auto supply. There are sold as "laptop automotive power" devices.
  8. #12


    Nov 30, 2010
    I recently approched a similar problem and found the answer at National Semiconductor's simple switcher page. I only needed one amp, but National's simple switcher page will calculate one for you. I think I just attached the answer I got. Take a peek and see if it is what you want.
  9. k7elp60

    Distinguished Member

    Nov 4, 2008
    You might try connecting a isolated DC to DC power supply in series with the 12V from the cigaretter lighter socket. Here is on @ mouser electronics. 418-EC9BW-24S33 this is a mouser sk#. I have done similiar before. The input is not isolated so it can be connected in parallel the the 12V from the plug. The output is isolated so the - output is connected to the + of the plug, and the +output of the powersupply and the - of the the ciagarette jack produces the 15V for the load.
  10. iONic

    AAC Fanatic!

    Nov 16, 2007
    @ #12 and k7elp60,

    both solutions do not seem to come close to the current requirements.