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PLL DRIVER CIRCUIT QUESTIONS *EDIT*

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StormInABottle

Sun Nov 24 2013, 06:19PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

Dr.DarkCurrent. With bridge leg. You mean the gate that goes to the GDT? And will this cap do? MKP4J041506F00KYSD. Also all the volts i have are 220V AC. Somewhere near 320V DC. I want the coil to only run CW.
And this datasheet

only covers up to 6 volts. I will run 12. So i still need the R1-R2-C1 values

XD. I am excited.

Dr. Dark Current

Sun Nov 24 2013, 07:24PM

Registered Member #152 Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384

A bridge leg is a combination of 2 switches, so 2 transistors and 2 diodes, a "half bridge".

Use the CD4046BE, not the 74HC version.

StormInABottle

Mon Nov 25 2013, 01:53PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

Will this cap work as a decoupling cap in the power section?

Here is a heavily modified schematic

Pay attention the control part. Specially C1 , R2 and the input voltages. And are the decoupling caps in their place?

I think this circuit is close to perfection

Dr. Dark Current

Mon Nov 25 2013, 06:31PM

Registered Member #152 Joined: Sun Feb 12 2006, 03:36PM
Location: Czech Rep.
Posts: 3384

You should use both R1 and R2 to set the range of the VCO so that the coil's resonant frequency lies somewhere in the middle. The UCCs need a somewhat larger decoupling caps, I would use 2.2 uF ceramics.

And yes, the cap from your first link will work. But you have them connected wrong in your diagram.

StormInABottle

Mon Nov 25 2013, 07:48PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

What i can't understand is how can a resistor be infinite ohms? And which would be better in terms of CW fire length. 5 regulated smexy volts from a computer psu. or 12 UNregulated volts from the same PSU. Or a weird combination of two weird PSUs combining the 12V and 3.3V X_X.. Also 10 Kohm would make my minimum frequency 300 khz. If i use 20 KOhm i should get 150 khz. 40 Kohm should give 75 khz. 80Kohm should give 37.5 KHz. So i guess i am supposed to leave out pin 11? Cause it asks for infinite ohms. Or give pin 11 1 Mohm? (I can get 500GOhm resistors but those are damn expensive X_X) Or can anyone just spoon feed me the values? I would really appreciate it :P
I will get to editing the values soon.
And can you please specify where the power section caps would be connected exactly X_X?. Sorry.

twist2b

Mon Nov 25 2013, 07:50PM

Registered Member #2086 Joined: Tue Apr 21 2009, 02:33AM
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Posts: 117

He's saying caps from source to ground as close to the mosfets as possible. And you only need 2, one for the top two because of how H bridge works. OK OK, here is an example of Steve's:

Notice the 10u Polypropylene caps.... For your's I don't think you would need D14-D18 as they are just for safety and energy dissipation control but IGBT's have built in diodes.... just need a larger heat sink I guess. Also the diodes across the resistors are unnecessary kind of... just another safety feature. Really all of them are because you might be driving the IGBT's at their limitations and don't want to damage them.

Than again I think the design I just linked is literally as good and safe as you are going to get... but whatever, price is a constituent.

StormInABottle

Mon Nov 25 2013, 08:15PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

I will get to editing later. As i am tired currently. What about the control part? Also. steve's circuit does not seem as simple as mine at the first look. I am sure my circuit would make an extraordinary instructable.
Also thanks for letting me understand decoupling. You always have something new to learn when you waste 6+ month trying to make a zvs eat as much power as possible.

R1 and R2 are driving me crazy.

TwirlyWhirly555

Mon Nov 25 2013, 08:40PM

Registered Member #4104 Joined: Fri Sept 23 2011, 06:54PM
Location: Uk .
Posts: 122

Put a resistor on both pins 12 and 11 but to get away with smaller resistor values use a larger timing capacitor on pins 6-7 such as 500pF or something

From what iver gather the idea is is one resistor sets the max range from 0 Hz and the the second resistor offsets the range

so using one resistor and the capacitor say you get 20Khz max VOC frequency . When you add the second timing resistor and for example offsets it by 5Kz , then the VOC with have a range from 5Kz to 25Khz ( still a 20Khz window ) The ratio between the 2 resistors I believe is to be around 1:1.5

To work it out I think its something like ( not so great example ) - find the max range you need so say for 40 KHz resonant find a resistor to give this max frequency then use the second resistor to off set it say by 20Khz then the VOC range becomes 20 to 60 KHz , thus the resonant frequency is in this range .

( actual resistors values will depend on the supply voltage and timing capacitor size )

This is how I believe it works , but don't hold me to it :P , I've only based this from what i've read / seen .

StormInABottle

Tue Nov 26 2013, 02:32AM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

50 pf is c1 , 10kohm is R1 1Megaohm is R2. At 5 volts Input. The range should be from 20 kHz, up to 300 kHz
Meow?

StormInABottle

Tue Nov 26 2013, 07:25PM

Registered Member #9252 Joined: Fri Jan 04 2013, 06:27AM
Location: Andromeda
Posts: 253

Here is an edited schematic.
I hope i wired the capacitors right. And i hope i got the values right.

If i didn't. Can someone modify them for me X_X. I use pixlr editor to edit. It's an online editor :P

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