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I am new in LTSpice simulation .I have prepared the schematic of the following DC to DC buck converter design in folder i.e. C:\Program Files\LTC\LTspiceIV\Rough\ . My aim is to make a charger for a smartphone that has 110Vdc input and {5Vdc, 2A} output.

I don't know which commands are required to be inserted in the schematic using simulate-> Edit simulation cmd option to see the results. I want to check the output voltage at the Vout node and Iout value using tester . Also I want to see the waveforms but don't know how to do it . So what changes should I do in schematic ?

Edit: By looking at one LTSpice Buck Converter tutorial on youtube, I added simulate->Edit simulation cmd->Transient->Stop time=100usec. When I click on RUN option, it is not showing any error but there is no waveform window. In the bottom of window of schematic,it is just showing stepping source 100% and iterations are changing continuously.

enter image description here enter image description here

.asc file
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  • \$\begingroup\$ Let us continue this discussion in chat. \$\endgroup\$ – a concerned citizen Nov 9 '16 at 7:15
  • \$\begingroup\$ Also, change to Alternate solver under Settings->SPICE if your models and schematic is sound and it still doesn't solve. \$\endgroup\$ – winny Nov 9 '16 at 10:06
  • \$\begingroup\$ @winny but where I am getting wrong? please see zip file in the schematic \$\endgroup\$ – user3559780 Nov 9 '16 at 10:42
  • \$\begingroup\$ @user3559780 Difficult to say but you approach the "limit" where simulations usually start to fail or nor converge. Vendor-supplied subcircuits can also be a culprit. Did you try the alternate solver? Can you replace the PWM is with just a voltage source PWM pattern and see if the simulation start? \$\endgroup\$ – winny Nov 9 '16 at 11:38
  • \$\begingroup\$ @winny No I didn't try any other design. I am new in designing the circuit for buck converter and operating the LTSpice software too. I don't know how to replace the PWM is with just a voltage source PWM pattern \$\endgroup\$ – user3559780 Nov 9 '16 at 11:51

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