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

Amplify current output?

  1. Jan 27, 2010 #1
    Does anyone have advice for how I can amplify a current output for low cost.
    Here are the details:
    I'd like to use a pulse generator to actuate a solenoid valve. The pulse generator has a variable voltage output (0-20V), and a current output of 0.2 - 0.22 A.
    The solenoid valve requires at least 12 V, and at least 0.32 A.

    I first thought I might simply be able to use a transistor, but I'm having a difficult time finding the right one.
    Does anyone know if this approach might work (and maybe able to recommend a transistor)?
    Or have a suggestion for a better approach?

    Thanks very much,
  2. jcsd
  3. Jan 27, 2010 #2
    If the solenoid requires 0.3 amps, you might consider using a small signal transistor like the PN2222A which is rated to handle 0.6 amps.

    Here is a possible schematic. The diode will protect the transistor from high voltage spikes coming from the solenoid when it is switched on/off.

    http://www.vlearnvshare.com/home/images/articles/NPN-DRIVER1.GIF [Broken]
    Last edited by a moderator: May 4, 2017
  4. Jan 27, 2010 #3
    Thanks very much! I'll give it a try.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook