Version 4.1
SHEET 1 2152 896
WIRE 208 64 32 64
WIRE 256 64 208 64
WIRE 448 64 336 64
WIRE 464 64 448 64
WIRE 32 128 32 64
WIRE 464 144 464 64
WIRE 32 256 32 208
WIRE 464 256 464 208
WIRE 464 256 400 256
WIRE 400 272 400 256
WIRE 208 432 32 432
WIRE 256 432 208 432
WIRE 448 432 336 432
WIRE 464 432 448 432
WIRE 560 432 464 432
WIRE 560 448 560 432
WIRE 32 496 32 432
WIRE 464 512 464 432
WIRE 560 544 560 528
WIRE 32 624 32 576
WIRE 464 624 464 576
WIRE 464 624 400 624
WIRE 560 624 560 608
WIRE 560 624 464 624
WIRE 400 640 400 624
FLAG 32 256 0
FLAG 400 272 0
FLAG 208 64 Vin
FLAG 448 64 Vout
FLAG 32 624 0
FLAG 400 640 0
FLAG 208 432 Vin_D
FLAG 448 432 Vout_D
SYMBOL cap 480 144 M0
SYMATTR InstName C1
SYMATTR Value 1µ
SYMBOL ind 352 48 R90
WINDOW 0 5 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName L1
SYMATTR Value 10µH
SYMATTR SpiceLine Rser=100m
SYMBOL voltage 32 112 R0
WINDOW 3 -74 101 Left 2
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR Value PULSE(0 10 1u 10n 10n 5u 10u)
SYMATTR InstName V2
SYMBOL cap 480 512 M0
SYMATTR InstName C3
SYMATTR Value 1µ
SYMBOL ind 352 416 R90
WINDOW 0 5 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName L2
SYMATTR Value 10µH
SYMATTR SpiceLine Rser=100m
SYMBOL voltage 32 480 R0
WINDOW 3 -74 101 Left 2
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR Value PULSE(0 10 1u 10n 10n 5u 10u)
SYMATTR InstName V1
SYMBOL res 544 432 R0
SYMATTR InstName R2
SYMATTR Value 3R
SYMBOL cap 544 544 R0
SYMATTR InstName C4
SYMATTR Value 3µF
TEXT 0 296 Left 2 !.tran 0 500u 0 100n
TEXT 664 104 Left 2 ;click on run\nfor the undamped circuit\nclick on Vin to plot its voltage\nclick on Vout to plot its voltage\n \nnow for the damped circuit \nclick on the plot window, then on plot settings/add plot pane.\nclick on Vin_D to plot its voltage\nclick on Vout_D to plot its voltage
TEXT 656 56 Left 4 ;Instructions
TEXT 352 -80 Left 5 ;LC and LC with damper circuits
TEXT 64 -16 Left 4 ;undamped circuit
TEXT 96 352 Left 4 ;Damped circuit
TEXT 656 392 Left 4 ;Circuit description
TEXT 664 440 Left 2 ;the waveforms for the undamped circuit don't make a lot of sense.\nthe output is not even the same frequency as the input.\nthe problem is that this circuit has no dissipative elements,\nso the energy bounces around between the L and the C,\nand its difficult to know what will happen,\nthis not much use, so we move on to the damped circuit.\nthe below "calculations" is a description of how to calculate the damper.
TEXT 672 672 Left 4 ;Calculations
TEXT 680 712 Left 2 ;firstly calculate the resonant frequency of the circuit.\nres freq = 1 / (2 x pie sq root(LC)) = 50 khz.\nthen work out the characteristic impedance of the circuit(Z)\nZ = 2 pie f L = 3 ohms.\nthis is the resistor value for the damper.\nthe capacitor in the damper wants to be about 3 times the \nfilter capacitor value