Device Status - Dynamic MOS Logic

Discussion in 'Homework Help' started by mau80, Oct 29, 2010.

  1. mau80

    Thread Starter New Member

    Oct 24, 2010
    Hi to all,

    I'd like to ask you help in resolving following exercises with Dynamic MOS Logic. I'm trying to follow solution provided by coursebook.

    In attachemnt file text.jpg that is the orignial text of exercise.

    For solve the exercise, the first operation that I've to do is find the operating state of each devices for any combination of value ( Hi or Low ) of input singnal.
    For this exercise my ( external ) input signal are Vi and Vck.

    So I split all the time of analysis, in varios part where my input signal take change.

    In attached file solution.jpg, I've drawn, with red mark, this istant of change.

    After that I compile a table where I write the state of each devices related to particuar input configuration Vi and Vck.

    Here I've found some problem, The solution provided by course book is in attached in file solution.jpg.
    Here I've marked with red the state where I have found problem to calculate the state of some devices.

    For istance:


    Time 1
    Solution says M4 is ON

    If Vy is Hi and M5 On
    For M4 Vgs = (Vy - Vy ) = 0 since M4 is nMos this must be OFF.


    Time 4
    Solution says M5 is ON

    If Ck = Low is Vy = Low
    For M5 Vsg = Low - Low ) = 0
    Since M5 is a pMos this must be OFF.


    I'd like to ask if you can help me to understand the result provided by solution.

    For the moment I'd like to understand the first step of determine operating state of devices.

    Thank you very much.