Version 3
SHEET 1 928 700
WIRE 268 384 268 380
WIRE 236 328 276 328
WIRE 300 348 300 380
WIRE 300 380 268 380
WIRE 312 352 312 380
WIRE 312 380 300 380
WIRE 312 332 312 312
WIRE 312 312 340 312
WIRE 340 312 344 312
WIRE 276 328 300 328
WIRE 268 380 236 380
WIRE 300 336 300 328
WIRE 236 332 236 328
WIRE 268 520 268 516
WIRE 236 464 276 464
WIRE 300 484 300 516
WIRE 300 516 268 516
WIRE 312 488 312 516
WIRE 312 516 300 516
WIRE 312 468 312 448
WIRE 312 448 340 448
WIRE 340 448 540 448
WIRE 276 464 300 464
WIRE 268 516 236 516
WIRE 300 472 300 464
WIRE 236 468 236 464
WIRE 212 384 212 356
WIRE 540 448 540 464
WIRE 540 484 540 504
WIRE 236 488 236 496
WIRE 212 356 236 356
WIRE 236 356 236 352
WIRE 564 480 564 504
WIRE 540 504 540 528
WIRE 564 468 564 448
WIRE 564 448 540 448
WIRE 576 484 576 504
WIRE 564 504 540 504
WIRE 576 464 576 448
WIRE 576 448 616 448
WIRE 616 448 664 448
WIRE 696 504 696 520
WIRE 664 504 696 504
WIRE 664 504 664 484
WIRE 664 448 664 464
WIRE 664 504 576 504
WIRE 664 448 684 448
WIRE 752 452 752 448
WIRE 752 448 700 448
WIRE 752 472 752 476
WIRE 752 496 752 504
WIRE 752 504 696 504
FLAG 696 520 GND
FLAG 268 384 GND
FLAG 340 312 e_noise
FLAG 276 328 white_noise_1
FLAG 268 520 GND
FLAG 340 448 i_noise
FLAG 276 464 white_noise_2
FLAG 540 528 GND
FLAG 212 384 GND
FLAG 616 448 i_noise_input
SYMBOL cap 684 452 R270
WINDOW 0 -12 8 Left 0
WINDOW 3 13 8 Left 0
SYMATTR InstName C1
SYMATTR Value {CVAR}
SYMBOL RES 668 488 R180
WINDOW 0 -16 14 Left 0
WINDOW 3 -30 4 Left 0
SYMATTR InstName R1
SYMATTR Value 10meg
SYMBOL E 312 328 R0
WINDOW 0 6 4 Left 0
WINDOW 3 6 26 Left 0
SYMATTR InstName E1
SYMATTR Value Laplace=sqrt( (9)**2 + ( (20.5)**2 * (1Hz) *2*pi / s) )
SYMBOL voltage 236 492 R0
WINDOW 0 10 14 Left 0
WINDOW 3 6 26 Left 0
WINDOW 39 -29 39 Left 0
WINDOW 123 9 5 Left 0
SYMATTR InstName V1
SYMATTR Value ""
SYMATTR Value2 AC 1V
SYMATTR SpiceLine Rser=0.01u Cpar=0.01pF
SYMBOL RES 240 356 R180
WINDOW 0 13 14 Left 0
WINDOW 3 -21 14 Left 0
SYMATTR InstName Rne
SYMATTR Value 60.5
SYMBOL RES 240 492 R180
WINDOW 0 13 14 Left 0
WINDOW 3 -21 14 Left 0
SYMATTR InstName Rni
SYMATTR Value 60.5
SYMBOL G 312 464 R0
WINDOW 0 6 4 Left 0
WINDOW 3 6 26 Left 0
SYMATTR InstName G1
SYMATTR Value Laplace=sqrt( (100)**2 + ( (620)**2 * (1Hz) *2*pi / s) )
SYMBOL RES 544 488 R180
WINDOW 0 7 26 Left 0
WINDOW 3 12 15 Left 0
SYMATTR InstName R5
SYMATTR Value 1
SYMBOL g 576 460 R0
WINDOW 0 6 4 Left 0
WINDOW 3 6 26 Left 0
SYMATTR InstName G2
SYMATTR Value 1
SYMBOL RES 756 476 R180
WINDOW 0 -53 21 Left 0
WINDOW 3 -19 11 Left 0
SYMATTR InstName R_electrode
SYMATTR Value 10k
SYMBOL voltage 752 472 R0
WINDOW 0 13 22 Left 0
WINDOW 3 6 26 Left 0
WINDOW 39 -29 39 Left 0
WINDOW 123 13 12 Left 0
SYMATTR InstName V_brain
SYMATTR Value ""
SYMATTR Value2 AC 10uV
text 608 332 Left 0 !;.noise V(e_noise) v1 dec 100 1000mHz 10kHz\n;.noise V(i_noise) v1 dec 100 1000mHz 10kHz\n.noise V(i_noise_input) v1 dec 100 100mHz 100Hz
text 608 316 Left 0 ;.temp 20 100 200
text 608 308 Left 0 ;.op
text 324 314 Left 0 ;1/f + white noise voltage source
text 608 324 Left 0 ;.ac dec 100 1000mHz 100kHz
text 318 362 Left 0 ;From AD620 datasheet:\neni at 1khz, g=100..1000 = 9nV/sqrt(Hz)\neni at 1Hz, g=100..1000 = 20.5nV/sqrt(Hz)\nrti 0.1Hz..10Hz = 0.28uVp-p\ncalculation:\nfnc=4.18827Hz
text 254 308 Left 0 ;1nV/sqrt(Hz)
text 314 450 Left 0 ;1/f + white noise current source
text 318 498 Left 0 ;From AD620 datasheet:\nini at 1khz, = 100 fA/sqrt(Hz)\nini at 1Hz, = 620 fA/sqrt(Hz)\nrti 0.1Hz..10Hz = 10 pAp-p\ncalculation:\nfnc=??? Hz
text 254 444 Left 0 ;1nV/sqrt(Hz)
text 606 392 Left 0 ;.PARAM CVAR=10nF
text 608 402 Left 0 !.step param CVAR LIST 10n 100n 1u 10u
text 492 536 Left 0 ;AD620 input noise current model
text 468 396 Left 0 ;At this point i_noise\nis factor 1e6 too big.\nTo compensate this \nscale the display down\nby factor 1e6
text 636 526 Left 0 ;1/2 brainmaster input \nhigh pass
text 744 526 Left 0 ;patient