Gentlemen,
Setting up voltage-controlled resistors is easy: R=(V(X)+0.01) or whatever. Works, always did. Doing the same with a capacitor fails with this error message:
Error on line 6 : c1 n002 0 c=(v(x)+0.01) Unable to find definition of model "c" * Unknown parameter "x" WARNING: Less than two connections to node X. This node is used by V4. Fatal Error: Missing capacitance value for "C1"
Both sims attached. What gives? Ideas how to make it work? Disregard the values that wouldn't make sense for the cap here, this is just to find the principal reason why the control method doesn't work with capacitors.
Variable resistor:
Version 4 SHEET 1 880 680 WIRE -80 -32 -256 -32 WIRE 64 -32 0 -32 WIRE 320 -32 64 -32 WIRE 64 0 64 -32 WIRE -640 16 -640 -48 WIRE -256 16 -256 -32 WIRE 320 16 320 -32 WIRE -640 112 -640 96 WIRE -256 112 -256 96 WIRE 64 112 64 80 WIRE 320 112 320 80 FLAG -256 112 0 FLAG -640 112 0 FLAG -640 -48 X FLAG 64 112 0 FLAG 320 112 0 SYMBOL voltage -256 0 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V2 SYMATTR Value 2.048 SYMBOL res 48 -16 R0 SYMATTR InstName R1 SYMATTR Value R=(V(X)+0.01) SYMBOL res -96 -16 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 0 56 VBottom 2 SYMATTR InstName R2 SYMATTR Value 2.49k SYMBOL voltage -640 0 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V4 SYMATTR Value PULSE(0 1 1n 1m 2m 1m 5m 1) SYMBOL cap 304 16 R0 SYMATTR InstName C1 SYMATTR Value 1p TEXT -472 -96 Left 2 !.tran 5m
Variable capacitor:
Version 4 SHEET 1 880 680 WIRE -80 -32 -256 -32 WIRE 64 -32 0 -32 WIRE 320 -32 64 -32 WIRE 64 0 64 -32 WIRE -640 16 -640 -48 WIRE -256 16 -256 -32 WIRE 320 16 320 -32 WIRE -640 112 -640 96 WIRE -256 112 -256 96 WIRE 64 112 64 80 WIRE 320 112 320 80 FLAG -256 112 0 FLAG -640 112 0 FLAG -640 -48 X FLAG 64 112 0 FLAG 320 112 0 SYMBOL voltage -256 0 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V2 SYMATTR Value 2.048 SYMBOL res 48 -16 R0 SYMATTR InstName R1 SYMATTR Value 100k SYMBOL res -96 -16 R270 WINDOW 0 32 56 VTop 2 WINDOW 3 0 56 VBottom 2 SYMATTR InstName R2 SYMATTR Value 2.49k SYMBOL voltage -640 0 R0 WINDOW 123 0 0 Left 2 WINDOW 39 0 0 Left 2 SYMATTR InstName V4 SYMATTR Value PULSE(0 1 1n 1m 2m 1m 5m 1) SYMBOL cap 304 16 R0 SYMATTR InstName C1 SYMATTR Value C=(V(X)+0.01) TEXT -472 -96 Left 2 !.tran 5m