UC3845 and DC DC Inverter question

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Hi!

I'm planing to make this inverter:
https://www.sportdevices.com/ignition/inverter.htm

And i have question about Pins 2 and 3 of UC3845. I'm interested do I need to connect anything to the pin 3 so that inverter works, and on wich turn(100% or 0%) this potentiometer which is connected to pin 2 needs to be set to have maximum voltage at output?

And for the last question, is this pot. be good for this application:
**broken link removed**

Thanks!
 

Pin 3 is the current sense, the main feature of this dc to dc is it is a current mode controller, so basically pin 2 senses a voltage representing the current through the inductor and opens the switches if the voltage is above a certain level(prevents killing your inductor), you could tie this to ground and disable the "watchdog" ability. pin 2 is used as a voltage divider to monitor its output and compensate for over voltage or under voltage ( think PID control). To be honest the datasheet for this part seems to be a bit lacking to me. but it seems to be optional. I am more familiar with the LT parts tbh.
 
Hmm, so then if I ground 3 pin it will work, or should I leave it just unconnected, on some examples of UC3845 I've seen it unconnected?

But still pin 2 remains as a problem.
Does anyone knows is this pot ok for this application, can it handle the power which is passing trough it:
**broken link removed**

- - - Updated - - -

Or does anyone know is there other simple scheme of inverter?
 

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