is it possible to change a NOT gate into a BUFFER?

[tzviel]

Hi Guys,

I have a small nice question:

If you take a CMOS inverter (NOT gate) that is constructed from a N-MOS at the
bottom and a P-MOS at the top, and you exchage between the two transistors- will it work as a buffer?

I have attached a picture for visual understanding.

Thanks
Tzviel

 

[IanP]

Unfortunately it won't work ..
To make a buffer you just cascade two NOTs: see picture below ..

Regards,
IanP

 

[wwfeda]

the size of the mos can be different too. the first set of cmos can be smaller than the 2nd set. It gives better driving capability.

You can think of a Not gate as a negative buffer.

 

[tzviel]

I am not sure...

If you put '1' to the gate of the N-MOS that is on the top it will open and the output will be '1'.
Same for '0' on the bottom.

Is it right or wrong?
(I can't attach a file for some reason so I rtied to draw)

--- vcc
|
|
--
-----0|
| --
---| |--------------------------- out
| -- |
------| ---- C
-- ----
| |
---- GND ----

CHANGED TO:

--- vcc
|
|
--
------|
| --
---| |----------------------- out
| -- |
------o| ----C
-- ----
| |
---- GND ----

 

[Davood Amerion]

If you take a CMOS inverter (NOT gate) that is constructed from a N-MOS at the
bottom and a P-MOS at the top, and you exchage between the two transistors- will it work as a buffer?

yes but output will not be full swing.
because of Vth NMOS and PMOS.

Regards,
Davood.