Paul R gray / Meyere
analysis & design of analog IC
chap 11
active Load mos is M3 M4
input nmos ise M1 M2
1/f noise =>
2kp/(fW1L1Cox) * [1+ { ( kn *un* (L1)^2) / ( kp up (L3)^2) }
if L3> 3* L1 noise is small
Thermal_noise => 4Kt *4 /(3* (2up*Cow (W1/L1) *Id)^0.5 ) *
[ 1+ { ( un *(W3/L3)) /(up * (W1/L1) ) } ^0.5 ]
if W1/L1 > W3/L3 noise small
another parameter is mos input Rg (gate impedance) , even thou mos have very high impedance , but I forget equation about Rg
Added after 37 minutes:
for MOS outut noise
v^2 = (4KT Rg) /3 * [ (gm* ro )^2 ]
Rg is gate impedance , if mos gate impedance is large
thermal noise is Large
V^2 (flicker) = K / (Cox *W*L*f)