Re[2]: Nonmonotonic Pulldown I-V curves

They are different, because the ON transistor adds a parallel (resistive) path
with its channel to the calmping diode.

Arpad

Jon,

It is my understanding that you were attempting to separate the bulk
diode currents from the pulldown I-V curves.

Therfore, I'm assuming that the one CMOS transistor in the report must
have the parasitic diodes internal to its model. Is this correct? This
would explain the huge (Amp range) bulk currents.

If it is, then isn't the test circuit I have drawn representative of
what you were modeling in the report(ignoring the parasitic diode from
source to bulk since it is shorted). My Id is the same as your Id etc.

I guess my question still is, given that you agree with everything I
have said above, how can the bulk currents between the "on" and "off"
cases be different?

I'm assuming that Ib = i_parasitic_diode and the diode current is a
function of the sweep voltage.

                                    Id ---------
                                  <--- | |
          -------------------------------------|Ammeter| SWEEP
          | | | |
          | | |i_parasitic ---------
          | | | diode |
       ---- --- V |
     | | ^ |
   --| | |-------- / \ |
   | | | | --- |
  / \ ---- | | |
 ( + ) | | ------------| |
 ( - ) | |Is ------- | |
  \ / | V |Ammeter| | Ib |
   | | ------- V |
  --- --- | ---
   - - --- -
                             -

Barry Katz-
Received on Wed Apr 20 13:45:51 1994