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Series RLC driver with PWM control

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Free_Will

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Hi friends,

I am sending you a schematic , I can drive a series rlc circuit directly with a microcontroller.However I need more current to drive it.I can not design a switching circuit or driver for it.I use a power n cahnnel mosfet but system is not working!Can you command on why it is not working.All I know is if gate-source voltage is greater than threshold voltage then drain-source will be short circuit or in other words mosfet will act as a switch and allow current flow from darain to source.But it is not working why?

Thanks.
 

flatulent

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There is no bias on the FET

Try this. Move the FET to the point between the battery and the resistor with the drain at the battery end. This will act like a source follower. If you want even more output swing, use a PFET with the source at the battery end.
 

marcosax

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Hi
The solution is: the circuit always have to draw current.
Try put a driver with 2 FETs
See a microchip driver TC4422
Need more current? Change source voltage.

Good luck! :)
 

Free_Will

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Hi,

Thank you very much for your responses.In conclusion I have discovered and experinced that this system can be drawn by a push-pull driver.System is working with push-pull manner.(See attachment)

By the way ,dear bunalmis the schematic sent by you is not working.I finally decided that series RLC must sent its energy back to ground.It could not do this in my first schematic and even in yours

Anyone who wants to test the schematics in real life or in elec. workbench should know that voltage across the capacitor is large(Greater than Vcc!Ex:30V) and sinusoidal.Otherwise system can not work properly.

Thanks...
 

bunalmis

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Hello,

My schematics works, simple induction oven uses this method.
(I used fast tristor instead of power mos.)

Your mistake is mos input signal indepentend from output.
capacitor will charge the power suplly voltage and system dont works If the gate signal not scyronize by series RLC current or Capacitor voltage.

Therefore pushpull system works well. Because capacitor find a discharge way. But pushpull system expensive.





Free_Will said:
Hi,

Thank you very much for your responses.In conclusion I have discovered and experinced that this system can be drawn by a push-pull driver.System is working with push-pull manner.(See attachment)

By the way ,dear bunalmis the schematic sent by you is not working.I finally decided that series RLC must sent its energy back to ground.It could not do this in my first schematic and even in yours

Anyone who wants to test the schematics in real life or in elec. workbench should know that voltage across the capacitor is large(Greater than Vcc!Ex:30V) and sinusoidal.Otherwise system can not work properly.

Thanks...
 

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