Is anyone using QSpice yet and if so can they tell me why a simulation of this simple jfet astable looks different in QSpice?
In LTSpice the simulated cycles (when it starts after about 40 seconds) look fine at the drain of each FET and repeat almost exactly.
With exactly the same circuit in QSpice there seems to be some kind of simulation granularity issue. Maybe there's a simulation parameter I need to adjust.
I'll try posting the QSpice schematic if anyone is interested but not sure how successful that will be.
QSpice includes the UF3C170400K3S which may be of use to those people wanting to simulate similar things.
Version 4.1 SHEET 1 1396 772 WIRE -16 -512 -240 -512 WIRE 496 -512 -16 -512 WIRE -16 -432 -16 -512 WIRE 496 -432 496 -512 WIRE -16 -272 -16 -352 WIRE 32 -272 -16 -272 WIRE 64 -272 32 -272 WIRE 176 -272 128 -272 WIRE 352 -272 304 -272 WIRE 496 -272 496 -352 WIRE 496 -272 416 -272 WIRE -240 -256 -240 -512 WIRE -16 -192 -16 -272 WIRE 496 -192 496 -272 WIRE 176 -128 304 -272 WIRE 176 -128 32 -128 WIRE 304 -128 176 -272 WIRE 448 -128 304 -128 WIRE 176 16 176 -128 WIRE 304 16 304 -128 WIRE -16 32 -16 -96 WIRE 496 32 496 -96 WIRE -240 208 -240 -176 WIRE -16 208 -16 112 WIRE -16 208 -240 208 WIRE 176 208 176 96 WIRE 176 208 -16 208 WIRE 304 208 304 96 WIRE 304 208 176 208 WIRE 496 208 496 112 WIRE 496 208 304 208 WIRE -240 240 -240 208 FLAG -240 240 0 FLAG 32 -272 D1 SYMBOL njf 448 -192 R0 WINDOW 0 0 -11 Left 2 WINDOW 3 -59 98 Left 2 SYMATTR InstName J1 SYMATTR Value 2N3819 SYMBOL njf 32 -192 M0 WINDOW 0 7 -9 Left 2 WINDOW 3 -64 100 Left 2 SYMATTR InstName J2 SYMATTR Value 2N3819 SYMBOL res -32 -448 R0 SYMATTR InstName R1 SYMATTR Value 3.3k SYMBOL res 480 -448 R0 SYMATTR InstName R2 SYMATTR Value 3.3k SYMBOL voltage -240 -272 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 12 SYMBOL res 480 16 R0 SYMATTR InstName R7 SYMATTR Value 1k SYMBOL res -32 16 R0 SYMATTR InstName R3 SYMATTR Value 1k SYMBOL res 160 0 R0 SYMATTR InstName R4 SYMATTR Value 10Meg SYMBOL res 288 0 R0 SYMATTR InstName R5 SYMATTR Value 10Meg SYMBOL cap 128 -288 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 100n SYMBOL cap 416 -288 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C4 SYMATTR Value 100n TEXT -200 240 Left 2 !.tran 100