Connect with us

Mosfet selection for switching a solenoid

Discussion in 'General Electronics Discussion' started by abuhafss, Jan 19, 2015.

  1. abuhafss

    abuhafss

    344
    10
    Aug 3, 2010
    Hi

    I need help for the selection of suitable mosfet (TO-220 package) for switching a solenoid with following parameters:

    Switching Frequency = 16 Hz
    On time = 20ms
    Off time = 41ms
    Duty Cycle = 32.78%
    Operating Voltage = 12V (for driver and solenoid)
    Solenoid Inductance = 1.2mH
    Current = 2.6 - 3.0A

    Also the value of the gate resistor for the mosfet.
     
    Last edited: Jan 19, 2015
  2. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,267
    Nov 28, 2011
    Do you want an N-channel or P-channel MOSFET?

    What supplier?

    There's a very wide range of MOSFETs that will be suitable.

    Here's a list of suitable N-channel devices from Digi-Key in order of ascending price. The main difference between them is RDSon and manufacturer.

    http://www.digikey.com/product-detail/en/PSMN022-30PL,127/568-7512-5-ND/2606361
    http://www.digikey.com/product-detail/en/PSMN017-30PL,127/568-9506-5-ND/3152043
    http://www.digikey.com/product-detail/en/FDP8880/FDP8880FS-ND/976840
    http://www.digikey.com/product-detail/en/IRFB7546PBF/IRFB7546PBF-ND/4772484
    http://www.digikey.com/product-detail/en/IPP065N03L G/IPP065N03LGIN-ND/1996760
     
  3. abuhafss

    abuhafss

    344
    10
    Aug 3, 2010
    Thanks for your response.

    Any N-Channel device from any supplier which match the parameters. I have tried 2SK1388 but it would get fairly warm. Next I am planning to try NB59N10D, IRF540, IRFZ24N, and IRFZ44 (which I already have with me).

    Keeping in view the operating voltage 12V and current 3A, actually I wanted to know what RDS(on) value would be the most suitable so that the heat dissipation is minimum.
     
    Last edited: Jan 19, 2015
  4. BobK

    BobK

    7,645
    1,663
    Jan 5, 2010
    The lowest one.

    Edit: When switching at 16Hz, the gate capacitance is not going to matter, at much higher frequencies it would.

    Bob
     
    abuhafss and Arouse1973 like this.
  5. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,267
    Nov 28, 2011
    Yeah, what Bob said.

    A TO-220 package doesn't need heatsinking if it's dissipating less than about 0.5W. You can calculate the maximum allowable RDSon from the power and the current:

    R = P / I2
    = 0.5 / 32
    = 56 mΩ

    All of the devices I suggested in post #2 have RDSon < 56 mΩ at VGS = 10V.
     
    abuhafss likes this.
  6. abuhafss

    abuhafss

    344
    10
    Aug 3, 2010
    Thanks all of you for your input.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-