I have a circuit that has either a ADA4625-1 or the AD8671 opamps at the input. With the 4625 as U1 it can find the dc operating point quickly however when I swap the opamp U1 for the for the AD8671 it gets hung up and rarely converges. Any tips would be very much appreciated. Im relatively new to using LTSpice.
Attached is the asc file for the circuit.
Version 4 SHEET 1 1608 680 WIRE -32 -112 -48 -112 WIRE 496 -112 48 -112 WIRE 192 -48 160 -48 WIRE 272 -48 256 -48 WIRE -352 32 -352 0 WIRE 32 32 0 32 WIRE 160 32 160 -48 WIRE 160 32 112 32 WIRE 192 32 160 32 WIRE 272 32 272 -48 WIRE 464 32 448 32 WIRE -144 80 -192 80 WIRE -48 80 -48 -112 WIRE -48 80 -64 80 WIRE -192 96 -192 80 WIRE -48 96 -48 80 WIRE 16 112 0 112 WIRE 160 112 160 32 WIRE 160 112 128 112 WIRE 208 112 160 112 WIRE 272 112 272 32 WIRE 288 112 272 112 WIRE 368 112 368 32 WIRE 384 112 368 112 WIRE -352 128 -352 112 WIRE -352 128 -384 128 WIRE 272 128 272 112 WIRE 464 128 464 32 WIRE 464 128 448 128 WIRE 496 128 496 -112 WIRE 496 128 464 128 WIRE 592 128 496 128 WIRE 704 128 672 128 WIRE 208 144 160 144 WIRE 384 144 368 144 WIRE -384 160 -384 128 WIRE 16 176 0 176 WIRE 128 176 128 112 WIRE 128 176 96 176 WIRE 368 176 368 144 WIRE -352 192 -352 128 WIRE 0 192 0 176 WIRE -192 208 -192 176 WIRE -48 208 -48 176 WIRE 0 288 0 272 WIRE 32 288 0 288 WIRE 160 288 112 288 WIRE -352 304 -352 272 FLAG -48 208 0 FLAG 368 176 0 FLAG -192 208 0 FLAG -384 160 0 FLAG -352 0 V+ FLAG 416 96 V+ FLAG -352 304 V- FLAG 416 160 V- FLAG 240 96 V+ FLAG 240 160 V- FLAG 160 224 0 FLAG 160 288 0 FLAG 96 112 0 FLAG 704 128 Vout SYMBOL Opamps\\ADA4625-1 416 64 R0 SYMATTR InstName U2 SYMBOL ind2 -64 80 R0 WINDOW 3 -65 96 Left 2 SYMATTR Value 300µH SYMATTR InstName Lp SYMATTR Type ind SYMATTR SpiceLine Rser=0.1R SYMBOL res 288 16 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 28 68 VTop 2 SYMATTR InstName R2 SYMATTR Value 3.3Meg SYMBOL res 464 16 R90 WINDOW 0 -2 58 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R5 SYMATTR Value 22k SYMBOL res 384 96 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R4 SYMATTR Value 2.2k SYMBOL res -48 64 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R7 SYMATTR Value 2K SYMBOL res 64 -128 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R6 SYMATTR Value 2k SYMBOL cap 256 -64 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 40pF SYMBOL voltage -192 80 R0 WINDOW 123 24 124 Left 2 WINDOW 39 -271 334 Left 2 WINDOW 3 -271 306 Left 2 SYMATTR Value2 AC 1 SYMATTR SpiceLine Rser=1R Cpar=1p SYMATTR Value SINE(0 0.01 1000 0 0 0 60) SYMATTR InstName V1 SYMBOL voltage -352 176 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value 16v SYMBOL voltage -352 16 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V3 SYMATTR Value 16v SYMBOL res 112 160 R90 WINDOW 0 22 66 VBottom 2 WINDOW 3 21 65 VTop 2 SYMATTR InstName R10 SYMATTR Value 30R SYMBOL res 112 96 R90 WINDOW 0 10 56 VBottom 2 WINDOW 3 14 58 VTop 2 SYMATTR InstName R11 SYMATTR Value 30R SYMBOL res 128 16 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 3 55 VTop 2 SYMATTR InstName R17 SYMATTR Value 245R SYMBOL res 128 272 R90 WINDOW 0 32 52 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R18 SYMATTR Value 245R SYMBOL ind2 16 128 R180 WINDOW 0 36 80 Left 2 WINDOW 3 36 40 Left 2 SYMATTR InstName LS1 SYMATTR Value 9H SYMATTR Type ind SYMBOL ind2 16 288 R180 WINDOW 0 36 80 Left 2 WINDOW 3 36 40 Left 2 SYMATTR InstName LS2 SYMATTR Value 9H SYMATTR Type ind SYMBOL res 688 112 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R14 SYMATTR Value 1k SYMBOL OpAmps\\AD8671 240 64 R0 SYMATTR InstName U1 SYMBOL res 144 128 R0 SYMATTR InstName R1 SYMATTR Value 1R TEXT -264 -32 Left 2 !K Lp Ls1 Ls2 1.0 TEXT 648 344 Left 2 !.tran 0 1 0.0001 0.001 uic TEXT 640 296 Left 2 !;noise v(Vout) V1 dec 100 0.1 100000 TEXT 640 256 Left 2 !;ac dec 100 0.1 100000 TEXT 632 208 Left 2 !.options cshunt=1.0e-15 TEXT 656 384 Left 2 !.options gmin=1.0e-12 TEXT 680 176 Left 2 !.options cshuntintern=1.0e-15
