Version 4 SHEET 1 2536 1752 WIRE 1264 1136 1152 1136 WIRE 1632 1136 1264 1136 WIRE 1824 1136 1632 1136 WIRE 1888 1136 1824 1136 WIRE 2160 1136 2080 1136 WIRE 2208 1136 2160 1136 WIRE 2080 1152 2080 1136 WIRE 2208 1152 2208 1136 WIRE 1152 1168 1152 1136 WIRE 1264 1168 1264 1136 WIRE 1632 1184 1632 1136 WIRE 1888 1184 1888 1136 WIRE 1392 1232 1376 1232 WIRE 1472 1232 1456 1232 WIRE 1824 1232 1824 1136 WIRE 1824 1232 1792 1232 WIRE 2208 1248 2208 1216 WIRE 1152 1280 1152 1248 WIRE 1264 1280 1264 1232 WIRE 1472 1328 1456 1328 WIRE 1888 1328 1888 1264 WIRE 1888 1328 1792 1328 WIRE 1968 1328 1888 1328 WIRE 2080 1328 2080 1232 WIRE 2080 1328 2032 1328 WIRE 2208 1328 2080 1328 WIRE 2336 1328 2208 1328 WIRE 1888 1344 1888 1328 WIRE 2336 1344 2336 1328 WIRE 2208 1360 2208 1328 WIRE 2080 1376 2080 1328 WIRE 1168 1424 1120 1424 WIRE 1280 1424 1248 1424 WIRE 1472 1424 1280 1424 WIRE 1840 1424 1792 1424 WIRE 1120 1440 1120 1424 WIRE 1280 1440 1280 1424 WIRE 2208 1440 2208 1424 WIRE 2336 1440 2336 1424 WIRE 1888 1456 1888 1440 WIRE 1120 1520 1120 1504 WIRE 1280 1520 1280 1504 WIRE 1376 1520 1360 1520 WIRE 1472 1520 1456 1520 WIRE 1904 1520 1792 1520 WIRE 1936 1520 1904 1520 WIRE 2048 1520 2016 1520 WIRE 2080 1520 2080 1456 WIRE 2080 1520 2048 1520 WIRE 2080 1536 2080 1520 WIRE 1632 1584 1632 1568 WIRE 2080 1632 2080 1616 FLAG 1888 1456 0 FLAG 1360 1520 0 FLAG 2080 1632 0 FLAG 1632 1584 0 FLAG 2208 1440 0 FLAG 1280 1520 0 FLAG 1120 1520 0 FLAG 2336 1440 0 FLAG 1152 1280 0 FLAG 1456 1328 0 FLAG 1376 1232 0 FLAG 2336 1328 OUT FLAG 1264 1280 0 FLAG 1152 1136 IN FLAG 2208 1248 0 FLAG 2160 1136 test FLAG 1904 1520 fb1 FLAG 2048 1520 fb2 SYMBOL NMOS 1840 1344 R0 SYMATTR InstName Q1 SYMATTR Value IRF7811 SYMBOL RES 1472 1504 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R1 SYMATTR Value 80.6K SYMBOL res 2064 1520 R0 SYMATTR InstName R2 SYMATTR Value 4K SYMBOL res 2064 1360 R0 SYMATTR InstName R3 SYMATTR Value 36.8K SYMBOL ind 1872 1168 R0 SYMATTR InstName L1 SYMATTR Value 1µ SYMBOL schottky 1968 1344 R270 WINDOW 0 32 32 VTop 0 WINDOW 3 0 32 VBottom 0 SYMATTR InstName D1 SYMATTR Value MBR735 SYMBOL polcap 2192 1360 R0 WINDOW 40 28 62 Left 0 WINDOW 3 40 38 Left 0 SYMATTR SpiceLine2 x2 SYMATTR Value 150µ SYMATTR InstName C1 SYMATTR SpiceLine Rser=.05 SYMBOL res 1264 1408 R90 WINDOW 0 0 56 VBottom 0 WINDOW 3 32 56 VTop 0 SYMATTR InstName R4 SYMATTR Value 22K SYMBOL cap 1104 1440 R0 SYMATTR InstName C2 SYMATTR Value 6800p SYMBOL cap 1264 1440 R0 SYMATTR InstName C3 SYMATTR Value 50p SYMBOL VOLTAGE 1152 1152 R0 SYMATTR InstName V1 SYMATTR Value 8 SYMBOL polcap 1456 1216 R90 WINDOW 0 0 32 VBottom 0 WINDOW 3 32 32 VTop 0 SYMATTR InstName C4 SYMATTR Value 4.7µ SYMBOL polcap 1248 1168 R0 SYMATTR InstName C5 SYMATTR Value 100µ SYMBOL PowerProducts\\LTC1871-7 1632 1376 R0 SYMATTR InstName U1 SYMBOL res 2320 1328 R0 SYMATTR InstName Rload SYMATTR Value 10 SYMBOL voltage 2032 1520 R90 WINDOW 0 -32 56 VBottom 0 WINDOW 3 49 80 VTop 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName VBode SYMATTR Value SINE(0 5m {Fmeas}) SYMBOL cap 2192 1152 R0 SYMATTR InstName C6 SYMATTR Value 20p SYMBOL res 2064 1136 R0 SYMATTR InstName R5 SYMATTR Value 100k TEXT 1624 1008 Left 0 !.tran 0 {Ttot} {Tset} TEXT 1528 1632 Left 0 ;PWL(0 0 1m 0 1.001m 0.01 1.5m 0.01 1.501m 0) TEXT 1624 760 Left 0 !.param Fmeas=5k ; actual frequency\n*\n.param N=10 ; 10 periods for FFT\n.param Tmeas=N*1/Fmeas ; simulation time for FFT\n.param Tset=1m ; setling time\n.param Ttot=Tset+Tmeas TEXT 1624 952 Left 0 !.FOUR {Fmeas} 5 -1 V(fb1) V(fb2) ; used for loop gain calculation TEXT 1144 560 Left 0 ;How BODEPLOT works\n \nRepeat the following two steps for \nevery frequency value of interest.\n \n1. Setup and run simulation\nApply a small sine voltage with \nthe frequency of interest to \nthe voltage source "Vbode".\nRun a transient simulation.\n \n2. Calculate Loop Gain (LG)\nOpen the Error-Log-file\nLook in the row harmonic number 1\nfor "Fourier component" and "Phase"\nLG-Magnitude=mag(V(fb2)/mag(V(fb1)\nLG Phase= phase(V(fb2))-phase(V(fb1))