Variables gat7e voltage for MOSFETs

Discussion in 'The Projects Forum' started by nuripaizail, Aug 5, 2008.

  1. nuripaizail

    Thread Starter New Member

    Jul 29, 2008
    MOSFETs require pulses at its gate terminal in order to work and the amount of current going through the source and drain terminals is depend on their characteristics and controlled by magnitude of the gate pulses. Normally, the magnitude of gate pulses is fixed and set to a nearly maximum allowable current can go through it.
    The problem with fixed type gate pulses is whenever overload or switching occurs; the MOSFETs will experience high current and may working beyond their safe operating area (SOA) which might destroy the MOSFETs.

    The objective of the project is to find a method on how the variable magnitude pulses gate could be implemented.
    The project should be able to adjust the amount of current flowing through the MOSFETs from 0A to maximum.
    The project will use PIC 16F84A

    Did any one have the idea to share regarding this project???
    let share it.......;)
    Last edited: Aug 5, 2008
  2. Tahmid

    Active Member

    Jul 2, 2008
    Do you have any idea regarding pwm? You can implement it with software pwm routine in pic 16f84a as this pic does not have hardware pwm module. With pwm routine as lookup table in program memory, and using 2 switches- one for increasing and another for decreasing, you can easily implement it. But you require thorough knowledge regarding programming,software pwm routine,lookup table and software switch debouncer routine etc. Nothing is impossible in this world, but most of us don't have the patience, energy and urge to learn through hardwork. You can try.
  3. nuripaizail

    Thread Starter New Member

    Jul 29, 2008
    I think, I can cope with the programming of pic 16f84a. The problem is i am still in dilemma with the hardware to be use.

    Do you have any suggestion?