Projects by members => Projects by members => Electrojolt => Topic started by: electrojolt on February 21, 2009, 17:38:25 pm
Title: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 17:38:25 pm
I'm working on a new stable Gated PWM.
We all know that Lawton's gated PWM has major flaws, including;
when one adjusts the frequency, the pulse width ratio also changes, for example you can have a 50% duty cycle, and as one changes the frequency, the duty cycle also changes.
my goal with this new circuit is to keep the duty cycle ratio the same as the frequency is adjusted for both, the main frequency and for the gating frequency. Also the pulse width can be changed and the freq stays the same.
I have done some progress and have the circuit almost done, just need to fine tune some components.
here are some shots:
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 17:42:26 pm
As soon as I have it fine-tuned I will post the schematic.
It will use two 555 and two LM311 chips.
I'm trying to get the circuit to operate in a very large range of freq.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 18:08:30 pm
Donaldwfc, to make you feel better, I'm no electronics expert, I'm also learning as I experiment. what helps me the most is that I'm a programmer so I apply my programing logic to electronics, it is very similar. each electronic component performs a function similar to functions in programs.
This circuit will be very easy for anyone to build.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 18:21:33 pm
I'm glad It helps.. and on the same idea, some IC chips can have several functions and others only one function.
For example the LM311 that I'm using, its function is to compare 2 volatges, once one voltage hits a threshold, it turns on an internal switch. below the threshold, the switch is off.
There are many ways of doing the same thing, just like in programing. we just have to get creative.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 18:34:07 pm
As soon as I have it fine-tuned I will post the schematic.
It will use two 555 and two LM311 chips.
I'm trying to get the circuit to operate in a very large range of freq.
Electrojolt , we dont need super high freq , something like 1khz to 150 khz sounds good .
Thx so much for this , we will pay you back.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 20:33:46 pm
dankie is correct.. technically we only need around 0-20 khz by what stan says but it would be nice you go a little further past that just to have it.. thank you for applying your expertise in fixing this problem..
outlawstc
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 20:38:28 pm
We all know that Lawton's gated PWM has major flaws, including;
when one adjusts the frequency, the pulse width ratio also changes, for example you can have a 50% duty cycle, and as one changes the frequency, the duty cycle also changes.
my goal with this new circuit is to keep the duty cycle ratio the same as the frequency is adjusted for both, the main frequency and for the gating frequency. Also the pulse width can be changed and the freq stays the same.
I have done some progress and have the circuit almost done, just need to fine tune some components.
here are some shots:
Great idea. The non synchrone adjusting of the DL circuit was always a problem!
br Steve
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 20:52:17 pm
Well, the 555 chip I'm using can go up to 2.4 Mhz. so we have plenty of room. now I just have to find out how far I can push the LM311.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 21:05:29 pm
Well, the 555 chip I'm using can go up to 2.4 Mhz. so we have plenty of room. now I just have to find out how far I can push the LM311.
Jolt I'm worried something will happen to you , plz release a quick draft to Stevie .
Not like this guy ..
http://hydrogencollective.com/
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 21, 2009, 21:44:53 pm
no need to worry.
and yeah, the circuit I'm working on works just like that.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 22, 2009, 16:16:18 pm
I tested how fast I can push the LM311 and I'm happy to say it can handle over 1.1 Mhz. so looks like this circuit will have a range from about 100 Hz to 1 Mhz.
There is a little problem at the high freq side, when adjusting the freq, the pulse width does change a little, but we can adjust the pulse width and maintain the same freq.
Maybe once in assembled in a PCB this issues will go away. test boards like the one I'm using has built in capacitance and they no good for high freq testing.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 22, 2009, 19:57:15 pm
I tested how fast I can push the LM311 and I'm happy to say it can handle over 1.1 Mhz. so looks like this circuit will have a range from about 100 Hz to 1 Mhz.
There is a little problem at the high freq side, when adjusting the freq, the pulse width does change a little, but we can adjust the pulse width and maintain the same freq.
Maybe once in assembled in a PCB this issues will go away. test boards like the one I'm using has built in capacitance and they no good for high freq testing.
Plz Electrojolt , the waiting is killing us .
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 22, 2009, 20:16:01 pm
patience dankie. lol let him get it right then we can see.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 22, 2009, 21:59:10 pm
I tested how fast I can push the LM311 and I'm happy to say it can handle over 1.1 Mhz. so looks like this circuit will have a range from about 100 Hz to 1 Mhz.
There is a little problem at the high freq side, when adjusting the freq, the pulse width does change a little, but we can adjust the pulse width and maintain the same freq.
Maybe once in assembled in a PCB this issues will go away. test boards like the one I'm using has built in capacitance and they no good for high freq testing.
Plz Electrojolt , the waiting is killing us .
Hey Dankie, just hang in there, Fortunatly I have a Full time Job and a Wife, I don't have much time to work on this, I have been working on it litle by litle and posting my progress. I think I have a stable circuit now and I'm starting to draw the schematic. I think I should have it ready by Mid week.
for those who want to build it will need two 555s, 2 LM311, 2 100K Pots, 2 10K pots, some 1K and 10K resistors, and some capacitors, 1 PNP and 1 NPN general purpose transistors, 2 fast switching diodes, those little red ones.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 22, 2009, 22:06:41 pm
I tested how fast I can push the LM311 and I'm happy to say it can handle over 1.1 Mhz. so looks like this circuit will have a range from about 100 Hz to 1 Mhz.
There is a little problem at the high freq side, when adjusting the freq, the pulse width does change a little, but we can adjust the pulse width and maintain the same freq.
Maybe once in assembled in a PCB this issues will go away. test boards like the one I'm using has built in capacitance and they no good for high freq testing.
Plz Electrojolt , the waiting is killing us .
hahahahahaha
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 23, 2009, 05:17:27 am
Donald,
I usualy get my stuff from mouser.com, newark.com, Ebay. I browse arround.
Title: Re: Stable Gated PWM Progress Working Circuit VIdeo
Post by: Login to see usernames on February 23, 2009, 05:18:47 am
I filmed my last circuit testing.
Title: Re: Stable Gated PWM Progress Schematic
Post by: Login to see usernames on February 23, 2009, 05:37:47 am
Ok, guys, here is my hard work.
Some resistors and capacitors may change once the circuit is mounted on a PCB. specificaly R1, R14, C2 and C6.
Also a few more capacitors will be added to extend the freq. range.
But for those that want to start testing the circuit, here it is:
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 23, 2009, 05:49:37 am
thank you
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 23, 2009, 06:11:16 am
I just noticed there is a 1k resistor missing from the base of the driver transistors to +12 volts.
I will update the circuit and add it.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 23, 2009, 07:22:39 am
I estimate about 30 bucks.
Here is the schematic with the missing resistor.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 23, 2009, 17:12:35 pm
OMG !!!!!!!!
Houston , we have no more problems .
Make those videos jolt , you deserve that fame .
Piss off Dave Lawton , its Electrojolt`s time to shine .
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 23, 2009, 17:28:57 pm
LOL!!!
Dankie, you are a funny guy.
Now get off the computer, get off your * , get some parts and go build a circuit.
I want to see it once you build it.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 23, 2009, 17:42:26 pm
Now get off the computer, get off your * , get some parts and go build a circuit.
I want to see it once you build it.
Lol I`m in class
At school I`m always on the computer .
Will be the first to try it .
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 23, 2009, 18:43:54 pm
Sorry,
the 2 driver transistors are general purpose PNP and NPN transistors, I used the ones from Radio Shack,
PNP = 2N2907
NPN = 2N4401
you can use almost any small switching transistor for this.
Now the Q is supposed to be Q3, is the Power Mosfet, here you have have a wide selection.
I use the IRF 640.
It all depends on the power you want and how fast you will be driving the circuit.
C1 .1uf C2 .1uf this is used to set the Gating frequency, other values needed for different freq range C3 1uf C4 .01uf C5 .1uf C6 3nf this is used to set the frequency. other values needed for different freq range C7 1uf C8 .01uf Q1 2N4401 Q2 2N2907 Q3 IRF640 R1 1k R2 100k R3 1k R4 1k R5 1k R6 2.2k R7 10k R8 1k R9 10k R10 2.2k R11 1k R12 10k R13 10k R14 1k R15 100k R16 1k U1 LM555C U2 LM555C U3 LM311 U4 LM311
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 24, 2009, 00:26:02 am
Sorry guys, I found another mistake.. It is all Dankie's fault for rushing me.. lol
R4 1k was connected to ground and needs to be connected to positive.
I updated the schematic above.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 24, 2009, 00:35:53 am
Ok,
I have build this circuit and i can confirm that Claudio made a nice circuit, again. :) :)
br Steve
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 24, 2009, 00:49:48 am
:) Ok do a vid to see :o
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 24, 2009, 01:33:26 am
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 25, 2009, 19:31:52 pm
Pochi,
That is my Video, not Stevie's...
If I remember right, on that video I was testing it at 500Khz.
it can operate at anything from 100Hz to 2.4Mhz., but to go up to 2.4Mhz you need a special 555 ship like: ALD1502
you just need to change the caps I mentioned.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 10, 2009, 16:35:37 pm
PCB
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 10, 2009, 18:02:31 pm
cool :)
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 13, 2009, 05:21:13 am
The PCBs are in.
Now is soldering time
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 13, 2009, 17:29:19 pm
I have been getting some PMs asking for the PCB file,
Let me tell a little story and why I will not be posting the file:
2 year ago +- , everyone wanted a good and reliable EFIE, so I designed one, tested it, proved it that it works, it took me 3 month working on it, I then published everyting so people could build it for them selfs. Well some guy stole all my stuff and started to sell it as if it was his circuit. I got very upset, I spent 3 month of hard work, and now that jerk was taking credit for my work.
this is the ASS: http://www.hhogear.com that stole my circuit.
I confronted him, and he said he never saw my circuit and that was his idea...... what a bunch of BS
Google: claudio cabete efie
So because of this I will never publish the PCB files, If someone is going to steal my work, they will have to spend time designing the PCB them selfs.
Now some of you here know that this post does not apply to you ;)
Claudio Cabete aka Electrojolt
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 13, 2009, 18:05:44 pm
Dam right claudio
Who is the member who asked for this ?
PCB is for sissy . good old pre-made board with holes and big jumper wires is the way to go .
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 13, 2009, 18:08:56 pm
Awesome! how many did you have made? i am going to want to buy at least 1
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 13, 2009, 18:13:08 pm
Awesome! how many did you have made? i am going to want to buy at least 1
This time around I only ordered 3 (minimum) just in-case I need to do some adjustments, after I assemble one and test it + any adjustments, I will ask who wants some and I will order accordingly.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 13, 2009, 21:57:23 pm
Very good Electrojolt. The Jolt circuit is a better one then the DL .
I also made a similair setup, but then with use of a clocked flipflop. It took me also weeks before i was happy. So you better protect the work well.
br Steve
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 14, 2009, 02:01:38 am
I have been getting some PMs asking for the PCB file,
Let me tell a little story and why I will not be posting the file:
2 year ago +- , everyone wanted a good and reliable EFIE, so I designed one, tested it, proved it that it works, it took me 3 month working on it, I then published everyting so people could build it for them selfs. Well some guy stole all my stuff and started to sell it as if it was his circuit. I got very upset, I spent 3 month of hard work, and now that jerk was taking credit for my work.
this is the * : http://www.hhogear.com that stole my circuit.
I confronted him, and he said he never saw my circuit and that was his idea...... what a bunch of *
Google: claudio cabete efie
So because of this I will never publish the PCB files, If someone is going to steal my work, they will have to spend time designing the PCB them selfs.
Now some of you here know that this post does not apply to you ;)
Claudio Cabete aka Electrojolt
Claudio is 100% correct that they stole his design and deny it. I built the circuit with Claudio's provided schematic and his invaluable help, way before it was even being legally sold on hydrogengarage.com The circuit works as said and is still in one of my cars.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 14, 2009, 16:15:09 pm
Thanks CowboyRX
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 16, 2009, 18:06:49 pm
1st Circuit almost done,
all 3 oshilators are working perfect.
need to mount the mosfets and some switches + wires.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 16, 2009, 21:36:10 pm
Beautiful
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 18, 2009, 03:36:18 am
Just make a video with Scope shots
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 18, 2009, 03:43:13 am
the video is unavailable ?
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 18, 2009, 04:02:22 am
Very well done! Is it safe to assume that this can be used instead of the Lawton and Bob Boyce PWM3G with no further modifications?
Thanks, and that is right.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 18, 2009, 06:34:04 am
Work of art circuit.
GREAT JOB ELECTROJOLT !!!
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 18, 2009, 06:45:46 am
Best pwm on the internet .
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on April 18, 2009, 14:37:46 pm
It seems that during my leave of absence to attend electronics school. That the bar has been raised higher and higher. It's very encouraging to see the progress on the site. It's also nice to see that some things don't change, But without disagreement, There is no progress. As long as you can prove your argument, And it's not just opinion.
It's also a lot less frustrating, To be able to look at diagrams, scope reading, ect and have a better understanding of what exactly is going on. Don't get me wrong, Class time is done, But the learning never stops ; ???
Spike ;D
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 02, 2009, 05:52:44 am
Alright, I'm happy with how this circuit works on the PCB.
I did have to make a small correction to the PCB.
If anyone here wants a PCB to assemble the Stable triple PWM, let me know.
It will cost $30.00 each.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 02, 2009, 06:16:01 am
I'm ready to buy!
What are you selling? just the PCB? do i need to find the parts separately or do they come too? or is it already assembled
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 02, 2009, 06:23:17 am
Just the PCB,
unfortunatly I don't have the time to asseemble them.
if you also need the parts, let me know and I see what I can do.
I'm thinking about making another small change, and that is to add an option to daisy chain the 3 PWMs,
so the 1st will gate the second, and the second will gate the 3rd.
Making it a little more flexible.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 02, 2009, 12:45:41 pm
i took apart a computer and a tv recently, i may have all the resistors and capacitors i need, how about i take a look around my radioshack and see how my luck is. if i think i can find what i need then i'll go with just the board, however i might just want to take the safe road for the first project and get the parts from you, or maybe some of them
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 02, 2009, 15:38:31 pm
I need at least 3 people to order the PCB, that is the minimum amount of PCBs I can order.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 02, 2009, 16:35:26 pm
Count me in for a PCB, with parts list and locations if possible.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 02, 2009, 16:53:19 pm
count me in for a pcb
I can get the parts on my own
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 04, 2009, 17:21:38 pm
If anyone else wants a PCB, make sure you let me know by the end of today. I will be placing the order tomorrow.
The PCBs are to facilitate the testing of the water cell project. Also will only provide the PCB for members of this Forum.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 05, 2009, 16:13:28 pm
I have my paypal account set up,
so the PCB is $30.00 including shipping.
also send me you mail address also.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 06, 2009, 01:32:40 am
I have a few questions, and i'll probably have a few more soon as well. I've never built a circuit before, but i learn quick ;)
Capacitors: you have them listed with capacitance, what about voltage? i was looking at some i pulled off a tv/computer/monitor, some are 50v, some are 160v, some i have to take a closer look at.
Resistors: they also have a wattage rating?
Looking at the radio shack web page i see IRF510 Mosfet, still do the job compared to IRF640? I'll have to check my local radio shack to compare as well.
I see the 2N4401 on the radio shack webpage, but not 2N2907... they have MPS2907, would that work?
What about the potentiometers, what kind of specs do they need?
Thanks for your help
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 06, 2009, 05:00:47 am
In electronic circuit the voltage rating of caps should be at least 25% more than the max voltage of the circuit. so 50 volts is fine
The schematic posted is the heart of the circuit, you can see that is has 2 oshilators.
when I designed the PCB, I added a 3rd oshilator.
all 3 oshilators are identical,
Here is the schematic with the 3 oshilators.
now you don't need to assemble all 3.
Now the IRF510 is no good, it will burn up on you very fast.
I like the IRF640, or FCPF11N60, this one is even better, Higher voltage, it will handle higher EMF.
now about the other little transistors, yes any small signal switching transistors will do. I usualy get the ones from radio shack, they have a box of variety of PNPs and NPNs 276-1604 and 276-1617
Resisitors, you can use 1/4 watt. I'm building mine using 1/8 watt, but it is the 1st time I'm building with 1/8. so not sure how well will work. so untill I report back, Use 1/4. those I know it works well.
Pots, well, here it is your choice, just get 100Ks and 10Ks. I have replaced a 100K with 50K, it works fine but that Freq range is not as wide.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 06, 2009, 19:05:33 pm
If you still need one for the order, count me in or if not, can you add me to the next batch ?
I'm leaving for work, let me know when you need the payment.
Nog.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 27, 2009, 01:18:11 am
ElectroJolt I am impressed.
I assembled my PWM, had a single problem and was the fact that I put in the wrong resistors for R6.
Once I installed the proper resistors 2.2k in those 3 positions this PWM worked better than I would have thought.
My signals are much clearer and accurate and think this is due to a combination of your circuit and the fact that I am using a couple 100k precision pots. I have to say the precision pots react with precision to the scope displayed waveform. Much more tighter tuning is available for me now.
This PWM blows the socks off my home brew Lawton pwm. I am running at a more controlled current now because of the duty cycle. Adjustments are much easier. Signals are cleaner for me.
Signaling options with 3 channel control are now possible. I really think this is a bonus, the options I now have with 3 channels of this PWM. Oh yah and the channel switchs can add control to the channel I'm currently using. An added extra. Don't think you need to because its pretty darn nice as it is. Great to have the added abilitys though.
The fact that the signals were very clean added to my inductors now I'm able to blend some harmonics. From the bounce factor of the inductors I get a clean scope display and can see how the waveform multiply's inside. Don't think I was able to see this before with such clarity on my scope. The clean signal and stabilty now allow me to actually see the waveform I'm making with the inductor harmonics and manipulate it.
I highly recomend this PWM to everybody that has a basic standard Lawton type or homebrew 555's type. This was definately a step up for me.
More options and clean signals. NICE!
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 27, 2009, 07:06:28 am
Thanks Komtek for the kind words,
I'm glad you like and using this circuit.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on May 28, 2009, 02:35:26 am
Board received, perfect condittion. also Highly recommended . Thank you very much :)
Nog.
Title: Re: Stable Gated PWM Progress
Post by: Login to see usernames on February 01, 2010, 05:50:20 am
I have been getting some PMs asking for the PCB file,
Let me tell a little story and why I will not be posting the file:
2 year ago +- , everyone wanted a good and reliable EFIE, so I designed one, tested it, proved it that it works, it took me 3 month working on it, I then published everyting so people could build it for them selfs. Well some guy stole all my stuff and started to sell it as if it was his circuit. I got very upset, I spent 3 month of hard work, and now that jerk was taking credit for my work.
this is the * : http://www.hhogear.com that stole my circuit.
I confronted him, and he said he never saw my circuit and that was his idea...... what a bunch of *
Google: claudio cabete efie
So because of this I will never publish the PCB files, If someone is going to steal my work, they will have to spend time designing the PCB them selfs.
Now some of you here know that this post does not apply to you ;)
Claudio Cabete aka Electrojolt
Dam those guys are crooks .
Gotta watch for em , they wont go far without the pcb file .