* Z:\tmp\asc_mix_bvbm4pog\mix_303.asc
* Generated by LTspice 26.0.1 for Windows.
M1 N003 VG 0 0 nch l='Ltab' w='Wtab'
Vgs VG 0 0.5
VDS N003 0 1.8
V1 +V 0 3.3
V2 -V 0 -3.3
C1 N002 N005 47p
R1 N005 N001 2.67K
R2 N001 N007 909
R3 N002 N001 909
C2 N001 0 220p
V3 N007 0 AC 1
C3 OUT N006 22p
R4 N006 N004 2.21K
R5 N004 N002 1.1K
R6 OUT N004 1.1K
C4 N004 0 470p
XU1 0 N005 +V -V N002 LT6220 ;pnba IN+)IN-)VCC)VEE)OUT
XU2 0 N006 +V -V OUT LT6220 ;pnba IN+)IN-)VCC)VEE)OUT
.model NMOS NMOS
.model PMOS PMOS
.lib C:\users\khalils\AppData\Local\LTspice\lib\cmp\standard.mos
.lib modely/cmos018.txt
.PARAM Ltab = table(n, 1,0.18u, 2,0.5u, 3,0.5u, 4,1u, 5,1u, 6,2u, 7,5u, 8,10u, 9,10u)
.PARAM Wtab = table(n, 1,0.22u, 2,1u, 3,2u, 4,2u, 5,5u, 6,5u, 7,10u, 8,10u, 9,40u)
.STEP param n 1 9 1
.MEAS DC VTH FIND V(VG) WHEN Id(m1)=1e-7*{Wtab/Ltab}
.dc VGS 0 1 1m
* 1MHz, 4th Order Butterworth Filter
* Library below included based on ModelFile attribute of instance XU1, XU2 (C:\users\khalils\AppData\Local\LTspice\lib\sym\OpAmps\LT6222.asy)
.lib LTC4.lib
.backanno
.end

* LTspice schematic (.asc):
Version 4.1
SHEET 1 1872 672
WIRE 224 64 -192 64
WIRE 224 144 224 64
WIRE 128 160 0 160
WIRE -192 192 -192 64
WIRE 0 192 0 160
WIRE 320 192 224 192
WIRE 128 224 128 160
WIRE 176 224 128 224
WIRE 224 256 224 240
WIRE 320 256 320 192
WIRE 320 256 224 256
WIRE 224 272 224 256
WIRE 912 48 800 48
WIRE 1088 48 992 48
WIRE 1328 64 1216 64
WIRE 1504 64 1408 64
WIRE 576 80 576 64
WIRE 688 80 688 64
WIRE 992 128 976 128
WIRE 1088 128 1088 48
WIRE 1088 128 1056 128
WIRE 1408 144 1392 144
WIRE 1504 144 1504 64
WIRE 1504 144 1472 144
WIRE 576 176 576 160
WIRE 688 176 688 160
WIRE 704 240 624 240
WIRE 800 240 800 48
WIRE 800 240 784 240
WIRE 848 240 800 240
WIRE 976 240 976 128
WIRE 976 240 928 240
WIRE 992 240 976 240
WIRE 624 256 624 240
WIRE 800 256 800 240
WIRE 1088 256 1088 128
WIRE 1088 256 1056 256
WIRE 1120 256 1088 256
WIRE 1216 256 1216 64
WIRE 1216 256 1200 256
WIRE 1264 256 1216 256
WIRE 1392 256 1392 144
WIRE 1392 256 1344 256
WIRE 1408 256 1392 256
WIRE 992 272 976 272
WIRE 1216 272 1216 256
WIRE 1504 272 1504 144
WIRE 1504 272 1472 272
WIRE 1536 272 1504 272
WIRE 1408 288 1392 288
WIRE 800 336 800 320
WIRE 624 352 624 336
WIRE 1216 352 1216 336
SYMBOL nmos4 176 144 R0
WINDOW 123 55 3 Left 2
SYMATTR Value2 l='Ltab' w='Wtab'
SYMATTR InstName M1
SYMATTR Value nch
SYMBOL voltage 0 176 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName Vgs
SYMATTR Value 0.5
SYMBOL voltage -192 176 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName VDS
SYMATTR Value 1.8
SYMBOL voltage 576 64 R0
WINDOW 123 44 91 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value 3.3
SYMBOL voltage 688 64 R0
WINDOW 123 44 91 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V2
SYMATTR Value -3.3
SYMBOL cap 1056 112 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C1
SYMATTR Value 47p
SYMBOL res 944 224 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 2.67K
SYMBOL res 800 224 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value 909
SYMBOL res 1008 32 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 909
SYMBOL cap 784 256 R0
SYMATTR InstName C2
SYMATTR Value 220p
SYMBOL voltage 624 240 R0
WINDOW 123 44 91 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V3
SYMATTR Value AC 1
SYMBOL cap 1472 128 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C3
SYMATTR Value 22p
SYMBOL res 1360 240 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R4
SYMATTR Value 2.21K
SYMBOL res 1216 240 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R5
SYMATTR Value 1.1K
SYMBOL res 1424 48 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R6
SYMATTR Value 1.1K
SYMBOL cap 1200 272 R0
SYMATTR InstName C4
SYMATTR Value 470p
SYMBOL opamps\\LT6222 1024 256 R0
SYMATTR InstName U1
SYMBOL opamps\\LT6222 1440 272 R0
SYMATTR InstName U2
FLAG 224 272 0
FLAG -192 272 0
FLAG 0 272 0
FLAG 128 160 VG
FLAG 576 176 0
FLAG 1536 272 OUT
FLAG 1024 224 +V
FLAG 1024 288 -V
FLAG 576 64 +V
FLAG 688 176 0
FLAG 688 64 -V
FLAG 976 272 0
FLAG 800 336 0
FLAG 624 352 0
FLAG 1440 240 +V
FLAG 1440 304 -V
FLAG 1392 288 0
FLAG 1216 352 0
TEXT -200 -168 Left 2 !.lib modely/cmos018.txt
TEXT -200 -120 Left 2 !.PARAM Ltab = table(n, 1,0.18u, 2,0.5u, 3,0.5u, 4,1u, 5,1u, 6,2u, 7,5u, 8,10u, 9,10u)
TEXT -200 -96 Left 2 !.PARAM Wtab = table(n, 1,0.22u, 2,1u, 3,2u, 4,2u, 5,5u, 6,5u, 7,10u, 8,10u, 9,40u)
TEXT -200 -72 Left 2 !.STEP param n 1 9 1
TEXT -200 -48 Left 2 !.MEAS DC VTH FIND V(VG) WHEN Id(m1)=1e-7*{Wtab/Ltab}
TEXT -200 -144 Left 2 !.dc VGS 0 1 1m
TEXT 552 376 Left 2 !.ac oct 10 10K 10Meg
TEXT 336 -24 Bottom 2 ;1MHz, 4th Order Butterworth Filter