Version 4
SHEET 1 1656 984
WIRE 368 -16 352 -16
WIRE 480 -16 416 -16
WIRE 416 16 416 -16
WIRE 368 32 368 -16
WIRE -16 80 -80 80
WIRE 48 80 -16 80
WIRE 160 80 96 80
WIRE -80 112 -80 80
WIRE 368 112 368 80
WIRE 416 112 416 96
WIRE 96 128 96 80
WIRE 48 144 48 80
WIRE -80 224 -80 192
WIRE 48 224 48 192
WIRE 96 224 96 208
WIRE 448 336 80 336
WIRE 80 368 80 336
WIRE 448 416 448 336
WIRE 448 416 352 416
WIRE 352 464 352 416
WIRE 368 464 352 464
WIRE 448 480 448 416
WIRE 448 480 432 480
WIRE 512 480 448 480
WIRE -48 496 -80 496
WIRE 80 496 80 432
WIRE 80 496 32 496
WIRE 112 496 80 496
WIRE 128 496 112 496
WIRE 256 496 208 496
WIRE 288 496 256 496
WIRE 368 496 288 496
WIRE 256 528 256 496
WIRE 256 624 256 592
FLAG -80 224 0
FLAG 48 224 0
FLAG 96 224 0
FLAG -16 80 in
FLAG 160 80 test
FLAG -80 496 in
FLAG 512 480 LP
FLAG 256 624 0
FLAG 112 496 1
FLAG 288 496 2
FLAG 368 112 0
FLAG 416 112 0
FLAG 480 -16 testab
FLAG 352 -16 in
SYMBOL voltage -80 96 R0
SYMATTR InstName V1
SYMATTR Value AC 1
SYMBOL e 96 112 R0
SYMATTR InstName E1
SYMATTR Value Laplace=1/(1+s*(R1+R2)*C2+s*s*R1*R2*C1*C2)
SYMBOL Opamps\\opamp 400 416 R0
SYMATTR InstName U1
SYMBOL Misc\\EuropeanResistor -64 512 R270
WINDOW 0 27 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName R1
SYMATTR Value {R1}
SYMBOL Misc\\EuropeanResistor 112 512 R270
WINDOW 0 27 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName R2
SYMATTR Value {R2}
SYMBOL cap 64 368 R0
SYMATTR InstName C1
SYMATTR Value {C1}
SYMBOL cap 240 528 R0
SYMATTR InstName C2
SYMATTR Value {C2}
SYMBOL e 416 0 R0
SYMATTR InstName E3
SYMATTR Value Laplace=1/(1+a*s/wg+b*s*s/(wg*wg))
TEXT -80 -48 Left 2 !.lib opamp.sub
TEXT -80 -8 Left 2 !.ac dec 100 100 10k
TEXT -80 -320 Left 2 !.param fg=1000\n.param wg=2*pi*fg\n.param a=1.3617 b=0.618\n.param C=10n\n.param C1=2*C \n.param C2=C\n.param R1=a/(2*wg*C2)+sqrt( (a/(2*wg*C2))**2-b/(wg*wg*C1*C2) )\n.param R2=b/(wg*wg*C1*C2*R1)
TEXT 32 -1008 Left 4 ;Lowpass F(s) = 1/(1+a*P + b*P^2)
TEXT -64 -768 Left 2 ;Bessel\n \nOrdnung i ai bi\n \n1 1 1,0000 0,0000\n \n2 1 1,3617 0,6180\n \n3 1 0,7560 0,0000 \n- 2 0,9996 0,4772\n \n4 1 1,3397 0,4889\n- 2 0,7743 0,3890
TEXT 200 -768 Left 2 ;Butterworth\n \nOrdnung i ai bi\n \n1 1 1,0000 0,0000\n \n2 1 1,4142 1,0000\n \n3 1 1,0000 0,0000\n- 2 1,0000 1,0000\n \n4 1 1,8478 1,0000\n- 2 0,7654 1,0000
TEXT 448 -792 Left 2 ;Tschebyscheff\n(0,5 dB Welligkeit)\n \nOrdnung i ai bi\n \n1 1 1,0000 0,0000\n \n2 1 1,3614 1,3827\n \n3 1 1,8626 0,0000\n- 2 0,6402 1,1931\n \n4 1 2,6282 3,4341\n- 2 0,3648 1,1509
TEXT 704 -792 Left 2 ;Tschebyscheff\n(3 dB Welligkeit)\n \nOrdnung i ai bi\n \n1 1 1,0000 0,0000\n \n2 1 1,0650 1,9305\n \n3 1 3,3496 0,0000\n- 2 0,3559 1,1923\n \n4 1 2,1853 5,5339\n- 2 0,1964 1,2009
TEXT -56 -944 Left 2 ;Literatur: http://www.fbeit.htwk-leipzig.de/~reinhold/Elektronik_Uni_Lpz/EL2_Kap_3.pdf\nProf. Dr. Wolfgang Reinhold 24/24\nHTWK Leipzig\nFakultät Elektrotechnik und Informationstechnik Kap_3_Filter.docx, 20.05.2011
TEXT 584 392 Left 2 ;View -> SPICE Error Log\nr1 in 1 17093.0344265151 \nr2 1 2 4579.09417430826 \nc1 lp 1 2e-008 \nc2 2 0 1e-008
TEXT 272 -272 Left 4 ;C1 > C2*4*b/a^2