Will this psu work as intended?

[ronsimpson]

Good job. You will be an expert on LTSpice soon.

1) you should get 150 to 160 volts from the power line. (one diode or four) I though the LTC7138 could only take 140 voltage. The spice model will not burn out like a real part.
2) with only one diode the value of C2 must be much much bigger.
3) some plugs are wired backwards.

With the external MOSFET the circuit can handle 110 or 220vac/dc with out any changes. MOSFET and Diode are the limiting factor for current and voltage.

 

[ajrenzetti]

Thank you for this information. I have to say, it is a little intriguing that the IC isn't rated to handle the rectified voltage of the common 115AC line. I'm going to build a pcb layout of your circuit and see if i can indeed fit it into the small constraints of my enclosure.

I am curious about what to use for the VCC, which the datasheet says can go to 25V. I cant find out what the minimum input current is, though. I'm thinking of either a resistor divider or simple voltage regulator IC. Unfortunately, it's proving to be quite difficult finding the correct voltage regulator that will provide ample current for the IC, while also being small and compact and able to carry 170VDC from the rectified input.

Also, what's the wattage rating for R6?

 

[ronsimpson]

Also, what's the wattage rating for R6?

R6 could have across it, 1 volt for 80% of the time, worst case. (low line, high load near current limit)

Attached is a new file.
L2 is some turns around L1 to make a 15 volt supply.
Normally R12,13 slowly charges up C9 from the power line. When the Vcc>=16 volts the IC starts working and pulling power. Too much to get from the 160Volts. Normally it takes 1/3 of a second to start up. This is not much in human years but in SPICE time it is FOR EVER. There is a ".IC V(VCC)=15.95V" command. Initial Condition the voltage of VCC node starts out at 15.95 volts. This makes the supply start up in 3mS so you don't have to wait 30 minutes in SPICE time.

For some strange reason, today, the .IC command did not want to work all the time. I had to close the scope window and restart the simulation some times.

This is how the start up works in many power line supplies. If the output is shorted out the 15V supply (VCC) will also collapse and the IC will reset needing some fraction of a second to restart. This is good for shorts. The linear supply would supply power into a short all the time, creating heat. This power supply will wake up 3 to 5 times a second and test to see if the short is still there. If so it will go back to sleep for a short while.