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    sg3525 pwm problem for 50hz 12v to 220v pwm....

    i have the following schematic for 50hz 12v to 220v dc. i have foud it from internet but not yet tested it. The problem is that how i can adjust pin no.2 the duty cycle by giving feed back from output 220 to obtain pwm? does it only require modification on the pin 2 or whole circuit needs to be changed?
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    Re: sg3525 pwm problem for 50hz 12v to 220v pwm....

    A feedback amplifier and compensation circuit involving pins 1,2 and 9 should be supplemented. The 230 VAC output needs to be rectified for the feedback.


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    Re: sg3525 pwm problem for 50hz 12v to 220v pwm....

    Please can u provide me a schematic ? i also have download the following diagrame
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    thanking you in anticipation



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    Re: sg3525 pwm problem for 50hz 12v to 220v pwm....

    I don't have a schematic, but the feedback circuit of your example can basically work. The feedback amplifier should probably have a PI rather than a pure I characteristic for faster response.



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    Re: sg3525 pwm problem for 50hz 12v to 220v pwm....

    please tell me which schematic i used i post 3 schematics. which one should i use



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    Re: sg3525 pwm problem for 50hz 12v to 220v pwm....

    Hi,you can simply used step down transformer let's say 6-9volt from your final output and rectified it,use simple pot and control pin 1 of your SG3525.



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    Re: sg3525 pwm problem for 50hz 12v to 220v pwm....

    You have only posted one schematic with AC voltage feedback, it's almost similar to what kabiru suggested.



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    Re: sg3525 pwm problem for 50hz 12v to 220v pwm....

    refer the circuit at SG3525 DC Converter 12V to +35V,-35V | Circuit Project Electronic
    This has PI feedback loop, Refer Pin 9,1, 2 connections.


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    Re: sg3525 pwm problem for 50hz 12v to 220v pwm....

    This has PI feedback loop, Refer Pin 9,1, 2 connections.
    Yes. The time constants would be however scaled by a factor > 100 according to the 60 Hz operating frequency of your inverter.


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