Battery charger circuit simulation

I have design this below circuit for 6v bat. charge

how could i simulate this in Kicad.
Test.sch (4.6 KB)

This is a general procedure for starting a simulation:

  • Install KiCad including ngspice.
  • Create the circuit in Eeschema.

— Both seems to be done already —

  • Find suitable device models for all active (transistors) and some passive (diodes) elements. Here Google is your friend, KiCad/ngspice do not provide these model data. You also will need a model for the battery!
  • Attach all models to the respective symbols in the circuit diagram.
  • Set the simulation conditions
  • Run the simulation.

A tutorial how to set-up and run simulations is http://ngspice.sourceforge.net/ngspice-eeschema.html. Especially you might have a look at chapter http://ngspice.sourceforge.net/ngspice-eeschema.html#BipAmp

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Just to remark that 20mA through the power indicator LED is far more than you need. 2k resistor would be more like it. Simulation won’t tell you this.

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This is going to be the hardest one, mainly because you need to first know exactly what you want to simulate in that circuit…instead of just saying “simulate this”.

Also, to clarify @kenyapcomau 's statement, the simulation can give you how much current is going through the LED, but there is nothing to warn you that it is too much or that it’s unnecessarily bright (as you would be able to easily see in real life). For example, if you are dissipating 500mW in a 250mW rated resistor, SPICE will not throw up a little animation for you showing it smoking and you won’t be able to smell it either.

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