H-Bridge growing pains What MosFets to use

Discussion in 'Homework Help' started by howdoesthatworkguy, Jul 23, 2007.

  1. howdoesthatworkguy

    Thread Starter Active Member

    Jul 23, 2007
    I am building a decoder for my model railroad. It basically users a Microchip PIC and decodes a single from a power supply/command station. Which in turn allows me to control each train independently. This is all called Digital Command Control or DCC. The problem I have is trying to figure out what MosFets to use in the H-Bridge. Trains have a typical 12V CAN motor. Up to
    2A and should not have any noise from the motor. By what I have read I need to make sure it can switch above 20KHz right ? I have also noticed that I would not need to use drivers if I use Logic Level MosFets correct?. So if I use a typical H-Bridge then the high side is going to be P-Channel and low side will be N-Channel. But this is the hard part, the data specs from companies is where I get lost, I am unsure what type of MosFets to choice from. Also, I want them in a SOT3 package, or something in SMD because of space constraints. I was looking at the ZXMHC3A01T8 from Zetex because it was in a very small package as a basic H-Bridge. Others I had a look at were ZXMN2B14FH because it seems to have a low gate drive requriement. But the ZXMN2B14FH is an N channel, and I can't find its P Channel counterpart. Can anyone point me in the right direction ?
  2. nanovate

    Distinguished Member

    May 7, 2007