Bi-Directional Switch using MOSFETS

Discussion in 'General Electronics Chat' started by sonar_abhi, Mar 30, 2016.

  1. sonar_abhi

    Thread Starter New Member

    Mar 19, 2016
    Hi Guys,

    Can anybody explain me the concept behind a bidirectional switch used commonly in battery chargers? Why are Mosfets not used in regular connection instead of a bidirectional configuration?

  2. Bordodynov

    Active Member

    May 20, 2015
    I'm in such cases, use two MOS transistor (p-channel). Enable consistent, connect the sources. Connect the valves. Between the gate and the source resistor (eg 10 kohms). Control gate open collector or drain. At high voltages have to add a resistor and zener diode.
    The battery protection circuit board using two n-channel transistor.
  3. sonar_abhi

    Thread Starter New Member

    Mar 19, 2016
    Actually what I want to ask is why do we use this configuration in battery chargers. If we normally connect N channel Mosfet's gate to a microcontroller (asuming we are using a Logic level Mosfet), connect the negative of the battery to the drain of the MOSFET and source to the ground, would it not work? This way only one MOSFET would work instead of two.
  4. AnalogKid

    Distinguished Member

    Aug 1, 2013
    Your circuit description does not make sense. You seem to have a specific circuit in mind. Please sketch it ans post it. There are many ways to use a MOSFET as a switch, and referring to an unknown battery charger does not give us any information.