Mc33025p
Luka
Take a look at the appnote for this IC ,I think you will have all protection you need with a very simple current monitoring circuit simple diode bridge with two resistors and cap.Check Marty Browns 280 watt HB while book has many errors for this circuit idea is same.Have a good one as an after thought I see a few of the SG3525 supplies with SS cap value larger than needed.
Luka
Take a look at the appnote for this IC ,I think you will have all protection you need with a very simple current monitoring circuit simple diode bridge with two resistors and cap.Check Marty Browns 280 watt HB while book has many errors for this circuit idea is same.Have a good one as an after thought I see a few of the SG3525 supplies with SS cap value larger than needed.
new supply
Luka
I have a new fullbridge that can supply up to 2kW by changing a couple of small daughter boards,pcb layout almost ready for pcb house,double sided and will use smd devices.The simulations in LTspice look ok so I don't expect any major problems.After test I will send you info to your PM if you like and I will post some here.
Luka
I have a new fullbridge that can supply up to 2kW by changing a couple of small daughter boards,pcb layout almost ready for pcb house,double sided and will use smd devices.The simulations in LTspice look ok so I don't expect any major problems.After test I will send you info to your PM if you like and I will post some here.
Dear Char1 ...
Can you please send me the libs and simulation of that smps?
I am desperatley searching for switchmode ic models and transformer models for LT Spice.
Right now i am trying to make a lib (.asy) for IRFH5020 transistor and irf do not have the model on their site.
I will be in dept forever if you could help me.
my email is:
savu_silviu@hotmail.com
best regards,
Savu Silviu
Can you please send me the libs and simulation of that smps?
I am desperatley searching for switchmode ic models and transformer models for LT Spice.
Right now i am trying to make a lib (.asy) for IRFH5020 transistor and irf do not have the model on their site.
I will be in dept forever if you could help me.
my email is:
savu_silviu@hotmail.com
best regards,
Savu Silviu
I have been waithing a long time for this, can't wait to see build, test's,...
And I also agree mc3x025 are great, I just won't use it where I don't need current limiting among other things
LTspice
Savu
In LTspice you can create your own models for inductors,transformers and other parts I have a zip file on that forum with models and simulations of Forward and HB supplies.I might be able to help further if you describe what topology you are working with as I have many files and models.Also a very good book is Christophe Basso's "Switch-Mode Power Supplies Spice Simulations and practical designs" all models and files with minor modifications can be used with LTspice as well as other spice software.
Savu
In LTspice you can create your own models for inductors,transformers and other parts I have a zip file on that forum with models and simulations of Forward and HB supplies.I might be able to help further if you describe what topology you are working with as I have many files and models.Also a very good book is Christophe Basso's "Switch-Mode Power Supplies Spice Simulations and practical designs" all models and files with minor modifications can be used with LTspice as well as other spice software.
2kW FB
As with custom of DIY Audio when finished I will post it on forum but don't expect much of a difference from other {hard switchers} (basic full bridge)will have fsw of 200kHz,DSS PCB,IGBT's,regulated and hopefully will supply 2kW ....but first testing(time) if needed you supply pfc.
As with custom of DIY Audio when finished I will post it on forum but don't expect much of a difference from other {hard switchers} (basic full bridge)will have fsw of 200kHz,DSS PCB,IGBT's,regulated and hopefully will supply 2kW ....but first testing(time) if needed you supply pfc.
Hello Chas1,
At the moment I am currently designing an off line full bridge smps with another member on this forum.
The smps will be built around SG3525 chip and will have hick-up current protection and over current protection, optical isolated voltage feedback, ETD 44 core wound with homemade litzwire and we intend to make it run at 1KW constant output.
Our intention is to post this project on this forum with details regarding everything:
- formulas used for the number of turns in the transformer
- formulas used for the number of turns in the current transformer
- formulas used for the TL431 voltage feedback
- formulas used for the choke inductors and capacitors at the output
- a small tutorial on how to make litzwire in you're home and the winding technique chosen for the power transformer
- PCB layout tips for smps
- snubber design and calculations
- EMI friendly techniques used for PCB and also enclosures of the power transformer and other EMI generating parts like the chokes
- scope readings in the critical parts (gates of the power fets, input and output of the power transformer, etc)
As we are not professional smps designers (all that we know about smps started on this forum), I was interested in LT Spice simulation for some parts of this circuit like inrush current and others in order, to limit the amount of money spent while building this (mosfets, chips, caps, etc cost money and I want to keep this project in a tight budget as much as possible).
best regards,
Savu Silviu
At the moment I am currently designing an off line full bridge smps with another member on this forum.
The smps will be built around SG3525 chip and will have hick-up current protection and over current protection, optical isolated voltage feedback, ETD 44 core wound with homemade litzwire and we intend to make it run at 1KW constant output.
Our intention is to post this project on this forum with details regarding everything:
- formulas used for the number of turns in the transformer
- formulas used for the number of turns in the current transformer
- formulas used for the TL431 voltage feedback
- formulas used for the choke inductors and capacitors at the output
- a small tutorial on how to make litzwire in you're home and the winding technique chosen for the power transformer
- PCB layout tips for smps
- snubber design and calculations
- EMI friendly techniques used for PCB and also enclosures of the power transformer and other EMI generating parts like the chokes
- scope readings in the critical parts (gates of the power fets, input and output of the power transformer, etc)
As we are not professional smps designers (all that we know about smps started on this forum), I was interested in LT Spice simulation for some parts of this circuit like inrush current and others in order, to limit the amount of money spent while building this (mosfets, chips, caps, etc cost money and I want to keep this project in a tight budget as much as possible).
best regards,
Savu Silviu
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project
Savu
What is thread number or have you started yet? I would suggest before you start you should define the parameters for your supply in detail(design goals)The output requirements are the important one's as they will determine the rest.The load...the load...the load(1kw has many definitions(output current and voltage) and this is detemined by load which will determine the size of the output inductor and filter cap and that will be determined also by your output ripple requirements and also your crossover frequency,the type of feedback used(if you use voltage or current mode)and as far as your control IC selection I would suggest that you consider the MC33025 part as it has features that will lower your parts count resulting in lower cost,easier design of protection circuits,smaller pcb footprint and lower cost even though it cost more than the SG3525..less parts more robust supply.I will monitor thread and supply any reference that I have if you like as far as LTspice I will post here the simulation of a FB supply along with the models and info I used.I am sure members of the forum can improve it.I need a couple of days.
Savu
What is thread number or have you started yet? I would suggest before you start you should define the parameters for your supply in detail(design goals)The output requirements are the important one's as they will determine the rest.The load...the load...the load(1kw has many definitions(output current and voltage) and this is detemined by load which will determine the size of the output inductor and filter cap and that will be determined also by your output ripple requirements and also your crossover frequency,the type of feedback used(if you use voltage or current mode)and as far as your control IC selection I would suggest that you consider the MC33025 part as it has features that will lower your parts count resulting in lower cost,easier design of protection circuits,smaller pcb footprint and lower cost even though it cost more than the SG3525..less parts more robust supply.I will monitor thread and supply any reference that I have if you like as far as LTspice I will post here the simulation of a FB supply along with the models and info I used.I am sure members of the forum can improve it.I need a couple of days.
If you use the ETD44 core set your osc freq will be ~200kHz,transfomer freq 100kHz anything lower will be a strech to reach 1kW in mho.There have been claims of ETD44 @50kHz with output power of 1kW but if you do the math it is very unlikely (~600 to 700watts).Also you can get 1kw from HB limitations will be current of mosfets used but you should consider IGBT's easier to use,cheaper.Simpler gate drive..there are some on ebay that might work.
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I had 730w, with over 1kw, 100Hz peaks (too low primary capacitance), 1kw with pfc no problem, no core heating, but I'm not saying this would be best for constant power
hello chas1.
the thread is not started now.
it will be started after we build the smps.
we are planing to use mosfets, full bridge topology, voltage feedback, output will be +/- 90Vdc (180v diferential output), constant power ~1kw at ~ 80KHz.
as we go along we will maby retake some decisions regarding the build. for the moment we are aiming to build it and make it stable somewhere arround 800W.
regards,
savu silviu
the thread is not started now.
it will be started after we build the smps.
we are planing to use mosfets, full bridge topology, voltage feedback, output will be +/- 90Vdc (180v diferential output), constant power ~1kw at ~ 80KHz.
as we go along we will maby retake some decisions regarding the build. for the moment we are aiming to build it and make it stable somewhere arround 800W.
regards,
savu silviu
I have two(2) ETD49's I just purchased. Can They be used?
I am willing HELP the new project as much as I can. I have only got a 100 mhz scope, is that OK?
Thanks, I like the entire IDEA, Concept and GOALS...
I am willing HELP the new project as much as I can. I have only got a 100 mhz scope, is that OK?
Thanks, I like the entire IDEA, Concept and GOALS...