Sinewave inverter prototype...

[ulywae]

Can I change the totem pole with uc3842/3 from scheme #324?
for drive dc dc stage.

thanks

 

[naseerak]

hi
can 3842 drive more than 1 fets?

 

[DeepOne]

change the totem pole with uc3842/3 from scheme #324?

possible try such change with STM8, but in scheme with ATMega8 some part of dead-times is formed by means of transistor inertias so can be not. And for UC3842 the uvlo tresholds is 16V_on/10V_off (8,5/7,9V for 3843).

can 3842 drive more than 1 fets?

this depends from fet gate charge and required switching speed.

 

[naseerak]

the frequency is 31khz

 

[DeepOne]

IRF3205 is around 150nC gate charge so may be one or two fets per 3842.
but this microcircuit is comparable on price with cheap mosfet and possible to put it with 1:1 proportions.

 

[naseerak]

and what if the frequency is halved to 15khz and the mosfet is 75n75

 

[DeepOne]

not so much important frequencies but how much time of the switching. if time of the switching will beside 300 nanoseconds the UC3842 is handle 3 75N75 mosfets, 500ns - five and so on. For UC3842 microcircuit it is necessary not to exceed pulsed current 1А and average 200mA.

 

[naseerak]

what about 4-- 75n75
and what about pc817 driving 4 mosfets (75n75)

 

[DeepOne]

what about pc817 driving 4 mosfets (75n75)

with max output current <50mA - this is joke, yes?

what about 4-- 75n75

i think you a capable to calculate this by themselfs )

 

[ulywae]

with ATMega8 i have preferred to do scheme like that (not tested) -

Sir do you have a full version for this? I want to try it but it is impossible if there is no voltage correction or feedback. Thank

 

[DeepOne]

Sorry, i have no full version for this scheme.

 

[DeepOne]

Worked version of converter already mentioned at message #378.
Tested only with small ACIM load.

 

[DeepOne]

final version. tested with "Kress WS710" angle grinder.

i think it is possible to double output power

 

[DeepOne]

Something similar, but with high frequency DC_DC stage

 

[schmitt trigger]

Congratulations on a very nice and challenging project. :thumbsup: :thumbsup:

I have a question: what schematic drawing program did you use? It looks very nice, and I specially like the fact that you can color-code the signals. It makes the schematic much easier to follow.

 

[DeepOne]

Congratulations on a very nice and challenging project.

Thank's, Schmitt trigger but last project is not ready (because radio-shops is locked on vacation)

drawing program did you use?

- that is "sPlan v7".

 

[DeepOne]

worked version (tested with 100W ACIM load)

 

[Mnt]

i have better idea, look at my thread here -> https://forum.allaboutcircuits.com/threads/mystery-strange-issue-class-d-amplifier.122460/

this is class d amplifier, but with attached small hf ATX trafo at the and before the filter this makes good inverter, powerfull with small transformer and 50hz sine out

 

[DeepOne]

apropos - a 1,5kW project with switchable (depends on load) DC_DC channels in step_up stage. not ready yet )

 

[Mnt]

i shared an external link in my post #398 and im warned, there you need registration.
sorry for that, here is my sch and idea but i realized that its possible only with HV PWM.
First boosting the voltage to 220-30-440-60 and then PWM that to 50Hz.

the ic used is tl494 and the mosfet driver is ir2111