infinitee00
Newbie level 3
Hello designers,
I was trying to derive the equations for threshold values of a Schmitt trigger from the CMOS circuit design and layout book by Jacob Baker.
https://books.google.com/books?id=N...ox-a&cd=8#v=onepage&q=schmitt trigger&f=false
However, on page 525, Equation 18.3, Baker assumes that the transistor M1 is in saturation when the Schmitt switches. But for M1 to be in saturation,
Vx > Vin-Vth1
or
Vx > Vx+Vth2-Vth1 (since Vin = Vx+Vth2 when M2 starts turning on)
or
Vth1 > Vth2
But due to body bias we know that Vth2 > Vth1. So is Baker's assumption incorrect or am I missing something.
Any insight would be great..
Thanks
I was trying to derive the equations for threshold values of a Schmitt trigger from the CMOS circuit design and layout book by Jacob Baker.
https://books.google.com/books?id=N...ox-a&cd=8#v=onepage&q=schmitt trigger&f=false
However, on page 525, Equation 18.3, Baker assumes that the transistor M1 is in saturation when the Schmitt switches. But for M1 to be in saturation,
Vx > Vin-Vth1
or
Vx > Vx+Vth2-Vth1 (since Vin = Vx+Vth2 when M2 starts turning on)
or
Vth1 > Vth2
But due to body bias we know that Vth2 > Vth1. So is Baker's assumption incorrect or am I missing something.
Any insight would be great..
Thanks