* SPICE netlist
XU1 0 IN1+ +V -V Sin+ AD8675 ;pnba In+)In-)V+)V-)OUT
V1 +V 0 5
V2 -V 0 -5
R1 Sin+ IN1+ 60.4k
C1 Sin+ IN1+ 12p
I1 IN1+ 0 PULSE(0 50u 0 10p 10p 10u 20u) AC 0.5
C2 IN1+ 0 100p
R2 IN1+ 0 1G
XU2 0 IN1- +V -V Sin- AD8675 ;pnba In+)In-)V+)V-)OUT
R3 Sin- IN1- 60.4k
C3 Sin- IN1- 12p
I2 IN1- 0 PULSE(0 50u 10u 10p 10p 10u 20u) AC 0.5 180
C4 IN1- 0 100p
R4 IN1- 0 1G
XU3 0 IN2+ +V -V Cos+ AD8675 ;pnba In+)In-)V+)V-)OUT
R5 Cos+ IN2+ 60.4k
C5 Cos+ IN2+ 12p
I3 IN2+ 0 PULSE(0 50u 5u 10p 10p 10u 20u) AC 0.5
C6 IN2+ 0 100p
R6 IN2+ 0 1G
XU4 0 IN2- +V -V Cos- AD8675 ;pnba In+)In-)V+)V-)OUT
R7 Cos- IN2- 60.4k
C7 Cos- IN2- 12p
I4 IN2- 0 PULSE(0 50u 15u 10p 10p 10u 20u) AC 0.5 180
C8 IN2- 0 100p
R8 IN2- 0 1G
XU5 N001 NC_01 Sin+ N002 N003 Sin- NC_02 N004 +V 0 +V 0 +V +V VCC VCC CNV SDOA SDOB N005 NC_03 Cos+ N006 N007 Cos- NC_04 N008 ADAQ4380 ;pnba OUTA-)IN2A+)IN1A+)SJA+)SJA-)IN1A-)IN2A-)OUTA+)VS+)VS-)REFIN)GND)IN_LDO)EN_LDO)OUT_LDO)VCC)CNV)SDOA)SDOB)OUTB-)IN2B+)IN1B+)SJB+)SJB-)IN1B-)IN2B-)OUTB+
V3 CNV 0 PULSE(3.3 0 50n 0.1n 0.1n 200n {1/fs})
C13 SDOA 0 10p
C14 SDOB 0 10p
XU6 Sin+ Sin- +V 0 Sine LTC6702 ;pnba In+)In-)V+)GND)OUT
XU7 Cos+ Cos- +V 0 Cosine LTC6702 ;pnba In+)In-)V+)GND)OUT
C9 N001 N002 82p
C10 N004 N003 82p
C11 N005 N006 82p
C12 N008 N007 82p
.tran 0 120u 20u
;ac dec 201 1k 1g
;noise V(SDOA) V1 dec 201 1 1g
.param fs 4e6

* LTspice schematic (.asc)
Version 4
SHEET 1 2448 1744
WIRE 136 -872 104 -872
WIRE 184 -872 136 -872
WIRE 424 -872 184 -872
WIRE 792 -872 424 -872
WIRE 952 -872 792 -872
WIRE -824 -808 -888 -808
WIRE -696 -808 -760 -808
WIRE 184 -808 184 -872
WIRE 424 -808 424 -872
WIRE 792 -808 792 -872
WIRE 952 -808 952 -872
WIRE -888 -744 -888 -808
WIRE -840 -744 -888 -744
WIRE -696 -744 -696 -808
WIRE -696 -744 -760 -744
WIRE -1160 -664 -1224 -664
WIRE -1128 -664 -1160 -664
WIRE -1016 -664 -1128 -664
WIRE -888 -664 -888 -744
WIRE -888 -664 -1016 -664
WIRE -824 -664 -888 -664
WIRE 1144 -664 1080 -664
WIRE -696 -648 -696 -744
WIRE -696 -648 -760 -648
WIRE -600 -648 -696 -648
WIRE -1128 -632 -1128 -664
WIRE -1016 -632 -1016 -664
WIRE -824 -632 -872 -632
WIRE -232 -632 -296 -632
WIRE -1224 -616 -1224 -664
WIRE -872 -600 -872 -632
WIRE -376 -568 -408 -568
WIRE -232 -568 -376 -568
WIRE 1144 -568 1144 -664
WIRE 1144 -568 1080 -568
WIRE 1192 -568 1144 -568
WIRE 1224 -568 1192 -568
WIRE -1224 -520 -1224 -536
WIRE -1128 -520 -1128 -568
WIRE -1016 -520 -1016 -552
WIRE -296 -520 -296 -632
WIRE -824 -456 -888 -456
WIRE -696 -456 -760 -456
WIRE -296 -440 -296 -456
WIRE -232 -440 -296 -440
WIRE 1128 -408 1080 -408
WIRE 1176 -408 1128 -408
WIRE -888 -392 -888 -456
WIRE -840 -392 -888 -392
WIRE -696 -392 -696 -456
WIRE -696 -392 -760 -392
WIRE 1176 -376 1176 -408
WIRE -232 -360 -296 -360
WIRE -296 -344 -296 -360
WIRE -1160 -312 -1224 -312
WIRE -1128 -312 -1160 -312
WIRE -1016 -312 -1128 -312
WIRE -888 -312 -888 -392
WIRE -888 -312 -1016 -312
WIRE -824 -312 -888 -312
WIRE -696 -296 -696 -392
WIRE -696 -296 -760 -296
WIRE -600 -296 -696 -296
WIRE -1128 -280 -1128 -312
WIRE -1016 -280 -1016 -312
WIRE -824 -280 -872 -280
WIRE 1176 -280 1176 -312
WIRE -1224 -264 -1224 -312
WIRE -872 -248 -872 -280
WIRE -376 -232 -408 -232
WIRE -232 -232 -376 -232
WIRE -1224 -168 -1224 -184
WIRE -1128 -168 -1128 -216
WIRE -1016 -168 -1016 -200
WIRE -296 -168 -296 -280
WIRE -232 -168 -296 -168
WIRE 1128 -120 1080 -120
WIRE 1176 -120 1128 -120
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WIRE -696 -88 -760 -88
WIRE 1176 -88 1176 -120
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WIRE -696 -24 -760 -24
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WIRE -232 -8 -376 -8
WIRE 1176 24 1176 -8
WIRE -296 40 -296 -72
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WIRE -1128 56 -1160 56
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WIRE -888 56 -888 -24
WIRE -888 56 -1016 56
WIRE -824 56 -888 56
WIRE -696 72 -696 -24
WIRE -696 72 -760 72
WIRE -600 72 -696 72
WIRE -1128 88 -1128 56
WIRE -1016 88 -1016 56
WIRE -824 88 -872 88
WIRE -1224 104 -1224 56
WIRE -872 120 -872 88
WIRE -296 120 -296 104
WIRE -232 120 -296 120
WIRE 1128 152 1080 152
WIRE 1176 152 1128 152
WIRE 1176 184 1176 152
WIRE -1224 200 -1224 184
WIRE -1128 200 -1128 152
WIRE -1016 200 -1016 168
WIRE -232 200 -296 200
WIRE -296 216 -296 200
WIRE -824 264 -888 264
WIRE -696 264 -760 264
WIRE 1176 280 1176 248
WIRE -888 328 -888 264
WIRE -840 328 -888 328
WIRE -696 328 -696 264
WIRE -696 328 -760 328
WIRE -376 328 -408 328
WIRE -232 328 -376 328
WIRE -296 392 -296 280
WIRE -232 392 -296 392
WIRE -1160 408 -1224 408
WIRE -1128 408 -1160 408
WIRE -1016 408 -1128 408
WIRE -888 408 -888 328
WIRE -888 408 -1016 408
WIRE -824 408 -888 408
WIRE -696 424 -696 328
WIRE -696 424 -760 424
WIRE -600 424 -696 424
WIRE -1128 440 -1128 408
WIRE -1016 440 -1016 408
WIRE -824 440 -872 440
WIRE -1224 456 -1224 408
WIRE -872 472 -872 440
WIRE 184 536 184 488
WIRE 424 536 424 488
WIRE -1224 552 -1224 536
WIRE -1128 552 -1128 504
WIRE -1016 552 -1016 520
WIRE -1032 728 -1032 712
WIRE -584 728 -584 712
WIRE -104 728 -104 696
WIRE 104 728 104 696
WIRE -1032 744 -1032 728
WIRE -584 744 -584 728
WIRE -1128 776 -1160 776
WIRE -1064 776 -1128 776
WIRE -680 776 -712 776
WIRE -616 776 -680 776
WIRE -920 792 -984 792
WIRE -904 792 -920 792
WIRE -472 792 -536 792
WIRE -456 792 -472 792
WIRE -1128 808 -1160 808
WIRE -1064 808 -1128 808
WIRE -680 808 -712 808
WIRE -616 808 -680 808
WIRE -104 856 -104 808
WIRE 104 856 104 808
WIRE -1032 872 -1032 840
WIRE -584 872 -584 840
FLAG -1224 -520 0
FLAG -600 -648 Sin+
FLAG -1160 -664 IN1+
FLAG -792 -680 +V
FLAG -792 -616 -V
FLAG -104 696 +V
FLAG -104 856 0
FLAG 104 696 -V
FLAG 104 856 0
FLAG -872 -600 0
FLAG -1128 -520 0
FLAG -1016 -520 0
FLAG -1224 -168 0
FLAG -600 -296 Sin-
FLAG -1160 -312 IN1-
FLAG -792 -328 +V
FLAG -792 -264 -V
FLAG -872 -248 0
FLAG -1128 -168 0
FLAG -1016 -168 0
FLAG -1224 200 0
FLAG -600 72 Cos+
FLAG -1160 56 IN2+
FLAG -792 40 +V
FLAG -792 104 -V
FLAG -872 120 0
FLAG -1128 200 0
FLAG -1016 200 0
FLAG -1224 552 0
FLAG -600 424 Cos-
FLAG -1160 408 IN2-
FLAG -792 392 +V
FLAG -792 456 -V
FLAG -872 472 0
FLAG -1128 552 0
FLAG -1016 552 0
FLAG 1176 24 0
FLAG 1176 -280 0
FLAG 1176 280 0
FLAG 1128 152 SDOB
FLAG 1128 -408 SDOA
FLAG 1128 -120 CNV
FLAG 184 536 0
FLAG 1192 -568 VCC
FLAG 136 -872 +V
FLAG -1032 872 0
FLAG -1128 808 Sin+
FLAG -1128 776 Sin-
FLAG -1032 728 +V
FLAG -920 792 Sine
FLAG -584 872 0
FLAG -680 808 Cos+
FLAG -680 776 Cos-
FLAG -584 728 +V
FLAG -472 792 Cosine
FLAG 424 536 0
FLAG -376 -8 Cos+
FLAG -376 328 Cos-
FLAG -376 -232 Sin-
FLAG -376 -568 Sin+
SYMBOL Opamps\\AD8675 -792 -712 R0
SYMATTR InstName U1
SYMBOL voltage -104 712 R0
SYMATTR InstName V1
SYMATTR Value 5
SYMBOL voltage 104 712 R0
SYMATTR InstName V2
SYMATTR Value -5
SYMBOL res -744 -760 R90
SYMATTR InstName R1
SYMATTR Value 60.4k
SYMBOL cap -760 -824 R90
SYMATTR InstName C1
SYMATTR Value 12p
SYMBOL current -1224 -616 M0
SYMATTR InstName I1
SYMATTR Value PULSE(0 50u 0 10p 10p 10u 20u)
SYMATTR Value2 AC 0.5
SYMBOL cap -1144 -632 R0
SYMATTR InstName C2
SYMATTR Value 100p
SYMBOL res -1032 -648 R0
SYMATTR InstName R2
SYMATTR Value 1G
SYMBOL Opamps\\AD8675 -792 -360 R0
SYMATTR InstName U2
SYMBOL res -744 -408 R90
SYMATTR InstName R3
SYMATTR Value 60.4k
SYMBOL cap -760 -472 R90
SYMATTR InstName C3
SYMATTR Value 12p
SYMBOL current -1224 -264 M0
SYMATTR InstName I2
SYMATTR Value PULSE(0 50u 10u 10p 10p 10u 20u)
SYMATTR Value2 AC 0.5 180
SYMBOL cap -1144 -280 R0
SYMATTR InstName C4
SYMATTR Value 100p
SYMBOL res -1032 -296 R0
SYMATTR InstName R4
SYMATTR Value 1G
SYMBOL Opamps\\AD8675 -792 8 R0
SYMATTR InstName U3
SYMBOL res -744 -40 R90
SYMATTR InstName R5
SYMATTR Value 60.4k
SYMBOL cap -760 -104 R90
SYMATTR InstName C5
SYMATTR Value 12p
SYMBOL current -1224 104 M0
SYMATTR InstName I3
SYMATTR Value PULSE(0 50u 5u 10p 10p 10u 20u)
SYMATTR Value2 AC 0.5
SYMBOL cap -1144 88 R0
SYMATTR InstName C6
SYMATTR Value 100p
SYMBOL res -1032 72 R0
SYMATTR InstName R6
SYMATTR Value 1G
SYMBOL Opamps\\AD8675 -792 360 R0
SYMATTR InstName U4
SYMBOL res -744 312 R90
SYMATTR InstName R7
SYMATTR Value 60.4k
SYMBOL cap -760 248 R90
SYMATTR InstName C7
SYMATTR Value 12p
SYMBOL current -1224 456 M0
SYMATTR InstName I4
SYMATTR Value PULSE(0 50u 15u 10p 10p 10u 20u)
SYMATTR Value2 AC 0.5 180
SYMBOL cap -1144 440 R0
SYMATTR InstName C8
SYMATTR Value 100p
SYMBOL res -1032 424 R0
SYMATTR InstName R8
SYMATTR Value 1G
SYMBOL ADAQ4380 456 -120 R0
SYMATTR InstName U5
SYMBOL voltage 1176 -104 R0
SYMATTR InstName V3
SYMATTR Value PULSE(3.3 0 50n 0.1n 0.1n 200n {1/fs})
SYMBOL cap 1160 -376 R0
SYMATTR InstName C13
SYMATTR Value 10p
SYMBOL cap 1160 184 R0
SYMATTR InstName C14
SYMATTR Value 10p
SYMBOL Comparators\\LTC6702 -1032 792 R0
SYMATTR InstName U6
SYMBOL Comparators\\LTC6702 -584 792 R0
SYMATTR InstName U7
SYMBOL cap -280 -520 M0
SYMATTR InstName C9
SYMATTR Value 82p
SYMBOL cap -280 -280 R180
SYMATTR InstName C10
SYMATTR Value 82p
SYMBOL cap -280 40 M0
SYMATTR InstName C11
SYMATTR Value 82p
SYMBOL cap -280 280 R180
SYMATTR InstName C12
SYMATTR Value 82p