Thanks. So it doesn't work with resistive loads? I just tested it out by using a calculator and tried different loads of 11 ohms, 25 ohms and 1.1k ohms, it worked but it was pretty arduous. I used RMS power calculations to get the readings.It's covered in the LTSpice Help files, but basically...
Your circuit must have:
1) Exactly ONE voltage source.
2) Exactly ONE current source set up as a load for the output.
3) One or more of Linear Technology's provided IC models (I haven't figured a way around this yet).
4) On "Edit Simulation Command", you must check the "Stop simulating if steady state is detected". Optionally, check the "Don't reset T=0 when steady state is detected" box; I find this useful.
[eta]
Check out the attached simulation; it's a 1.5v to 30v buck supply using an LT1171 2.5A 100kHz switcher. Tile the panes vertically. After the simulation finishes running, click on View -> Efficiency Report -> Show on Schematic.
Then click View -> Zoom to fit.
by Jake Hertz
by Duane Benson
by Jake Hertz