wesspower
Junior Member level 1
To Analog IC helper :
I recently design OP-AMP , and got very big issue with current mirror in OP-AMP circuit. Please download the circuit ( that is attachment) , Within the white square, that is the simple current mirror to provider current for different AMP (1st stage) .
My problem is that I set 40u A in i1 , because of M10 and M5 has the same width and length. i2 must be 40u as well by the theory of current mirror , but in my simulation , i2 actually is 900u . how does this happen to that circuit ?
Please help me with your expertise
Thank you guys.
The model file I use during the simulation
simulator lang=spice
.model nmos nmos
+ level=1 vto=1 kp=16u gamma=1.3 lambda=0.01
+ phi=0.7 pb=0.80 mj=0.5 mjsw=0.3 cgbo=200p cgso=350p cgdo=350p
+ cj=300u cjsw=500p ld=0.8u tox=80n
.model pmos pmos
+ level=1 vto=-1 kp=8u gamma=0.6 lambda=0.02
+ phi=0.6 pb=0.50 mj=0.5 mjsw=0.25 cgbo=200p cgso=350p cgdo=350p
+ cj=150u cjsw=400p ld=0.8u tox=80n
I recently design OP-AMP , and got very big issue with current mirror in OP-AMP circuit. Please download the circuit ( that is attachment) , Within the white square, that is the simple current mirror to provider current for different AMP (1st stage) .
My problem is that I set 40u A in i1 , because of M10 and M5 has the same width and length. i2 must be 40u as well by the theory of current mirror , but in my simulation , i2 actually is 900u . how does this happen to that circuit ?
Please help me with your expertise
Thank you guys.
The model file I use during the simulation
simulator lang=spice
.model nmos nmos
+ level=1 vto=1 kp=16u gamma=1.3 lambda=0.01
+ phi=0.7 pb=0.80 mj=0.5 mjsw=0.3 cgbo=200p cgso=350p cgdo=350p
+ cj=300u cjsw=500p ld=0.8u tox=80n
.model pmos pmos
+ level=1 vto=-1 kp=8u gamma=0.6 lambda=0.02
+ phi=0.6 pb=0.50 mj=0.5 mjsw=0.25 cgbo=200p cgso=350p cgdo=350p
+ cj=150u cjsw=400p ld=0.8u tox=80n
