NgSpice Simulation Errors with linear regulator

Drawn in KICAD 8, this circuit is planned to provide a 3.6V (maximum current of 1.2A) by V2 before reaching to linear regulator to level down the voltage to 3.3V.
I expect the voltage out of the battery have a gradual growth from zero to 3.6V in nodes n1 and n2 . as well as the current across the capactiors to ultimately get a 3.3V output of the MCP1700.

My problem is that while I don’t get any particular errors by ERC (Electrical Rules Checker), I don’t get anything like what I expect to see in simulation. Can anyone spot problems with this circuit? or initial conditions? or even time values?

Thank you.

Pin 1 of U1 is connected with nothing.
V2 ‘-’ pin is connected to the rest of circuit only by capacitors - you will certainly not get any DC current from it.
If you expect 1.2A flowing through 1k resistor than you assume voltage drop of 1200V at this resistor.

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Thank you for your comment.
Do you recommend any connection other than GND for Pin 1 of U1? Do you also have any recommendation for V2 connection other than through circuit? I will also lower down the resistor value as you mentioned.
Thank you again for your help.

Do you understand that if something is connected to GND and nothing else is connected to GND than this something is connected with nothing because GND is only a name of net and not gives automagically any connection?

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I understand it :slight_smile: but because I was following the data sheet of the LDO I’m using MCP1700-3302 then this configuration happened which obviously not working :slight_smile: that’s why I’m asking for your help.

What @Piotr is subtly pointing out is the only part of your circuit that is grounded in the IC. The rest of the circuit needs a ground. Maybe the bottom of V2?

awesome, thank you. Do you think this updated version looks better? I didn’t get any ERC error regarding V2, but what can I do for the GND connection of C2, MCP1700, and C3?

Why not join all the gnds together?

Something like this arrangement (with your additional symbols) is a lot clearer.

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Awesome, thank you. I created the circuit you propose, but still have the error for GND connection, can you point me to a probable issue? Thank you for your help :slight_smile:

The warning should have a message in the dialogue box. What does that message read?

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I changed it abit again but still get the same error - “Input power pin not driven by any output power pins”.

You probably missed:

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Thank you, I read it through. Apparently as long as the simulation makes sense the errors can be igonored. cheers.