.

The attached is an ltspice for an inverter circuit which i copied from the internet. However there are no models for the diodes( 1N4007) and the transistors (tip41 and tip42). Does anyone know of equivalent components in ltspice I could use instead?
Furthermore I know the 555 tim(er is producing a square wave OK bit it is all postive (from 0 volt to 12volts). Does the npn amplify from 6 to 12 volt range and the pnp amplify from 0 to 6 volt range?

 

hi ntetlow,
We need to know the specification of the circuit.?
E

If that image is a LTSpice asc file , the Base of the top transistor Q1 is not connected.

 

hi ntetlow,
We need to know the specification of the circuit.?
E

If that image is a LTSpice asc file , the Base of the top transistor Q1 is not connected.

Thanks. I hadn't noticed that.

 

Did you see the questions along with the ltspice?

 

hi ntetlow,
We need to know the specification of the circuit.?
E

If that image is a LTSpice asc file , the Base of the top transistor Q1 is not connected.

Forgive my ignorance. I don't know what you mean by that. I got the circuit from
https://www.electronicshub.org/12v-dc-220v-ac-converter-circuit/.

 

hi,
Replace your standard.dio in the 'cmp folder of LTS., it has all the diodes.
To upload this file I have had to change it to .txt, change it back to.dio

I will look for the TIP's.
E

Update:
Edit the standardbjt.txt to standard.bjt
Replace your standard.bjt in the 'cmp' folder with this one, all the BJTs

 

Note: When posting questions involving a simulation, it helps us if you also post your asc file.

 

hi,
Replace your standard.dio in the 'cmp folder of LTS., it has all the diodes.
To upload this file I have had to change it to .txt, change it back to.dio

I will look for the TIP's.
E

Update:
Edit the standardbjt.txt to standard.bjt
Replace your standard.bjt in the 'cmp' folder with this one, all the BJTs

 

Thank you Eric for the diode and bjt parts. I wonder at your thoughts on the second question i asked. The circuit uses 2 resistors, one for the postive part of the square wave and the other for the negative. The trouble is the square wave out of the 555 timer is all positive, from 0 to 12 volts. This is copied from something that's supposed to work, how come it doesn't?

 

hi nt,
Do you have an LTS asc file you could post.?
E

 

The circuit uses 2 resistors, one for the postive part of the square wave and the other for the negative. The trouble is the square wave out of the 555 timer is all positive,

When the pulse is high (12V), the NPN conducts, the PNP is off, and when low (0V), the PNP conducts, theres no negative involved here

 

hi,
Replace your standard.dio in the 'cmp folder of LTS., it has all the diodes.
To upload this file I have had to change it to .txt, change it back to.dio

I will look for the TIP's.
E

Update:
Edit the standardbjt.txt to standard.bjt
Replace your standard.bjt in the 'cmp' folder with this one, all the BJTs

 

Thanks Eric. Attached is the asc file.

 

hi nt,
Ran your sim, that circuit is a poor design.
What voltage and current do you expect across the 1k output load.?
E

EDIT:
You do not have L1 and L2 K coupling factor. !!

Try this it works , but its still awful.!

 

Tony VanRoon invented that horrible circuit ages ago:
1) Its output is a squarewave that is OK for low power old fashioned and obsolete incandescent light bulbs. Modern electronic products rely on the higher peak voltage of a sinewave.

2) It has very poor voltage regulation when loaded because of all its voltage losses:
a) With a 12.0V supply and no load, the output of the 555 is from 0V to 10.7V. The output of the diodes is 10.7V - 1.3V= 9.4V, the output of the resistors is the same and the output of the transistors is 9.4V - 1.3V= 8.1V peak to peak. The 12V to 220V transformer steps up the output voltage to only 148.5V which is too low.

b) With a 12V supply and a 35W load, the output of the 555 is 12V - 4V= 8V p-p, the output of the diodes is 6.6V p-p, the output of the resistors is 3.1V p-p, the output of the transistors is 0.5V p-p and the output of the transformer is only 9.2V which is WAY TOO LOW!