https://www.onsemi.com/pub/Collateral/HBD853-D.PDF
I can actually see the active PFC components in the cobra SMPS. Hypex does not describe whether they us passive PFC + soft switching or full
active PFC. Looks like the Cobra has both. This (my) PC's Seasonic also has that extra inductor and mosfet for full active PFC. that why my
AC line is so quiet right now. Cheap PS's will turn the AC line into a "transmitter" ... real cheap passive (attempt) at PFC.. typical phone charger sucks.
Why bother to get clean output while you trash the line ??
I can actually see the active PFC components in the cobra SMPS. Hypex does not describe whether they us passive PFC + soft switching or full
active PFC. Looks like the Cobra has both. This (my) PC's Seasonic also has that extra inductor and mosfet for full active PFC. that why my
AC line is so quiet right now. Cheap PS's will turn the AC line into a "transmitter" ... real cheap passive (attempt) at PFC.. typical phone charger sucks.
Why bother to get clean output while you trash the line ??
Commercial SMPS are expensive and you can't expect to repair it in case of a failure.
Would be a very cool option if we could have a diy friendly one.
I know the difficulties of such an implementation.
The pcb is very-very critical and the construction of the chopping transformer demanding,i don't trust myselfto do this
Would be a very cool option if we could have a diy friendly one.
I know the difficulties of such an implementation.
The pcb is very-very critical and the construction of the chopping transformer demanding,i don't trust myselfto do this
I use Hypex SMPS1200A400 in my Wolverine build and the amp is really a beast!!
Gaetano
Besides there is also very dangerous voltage which needs to be very carefully managed in an SMPS building...Commercial SMPS are expensive and you can't expect to repair it in case of a failure.
Would be a very cool option if we could have a diy friendly one.
I know the difficulties of such an implementation.
The pcb is very-very critical and the construction of the chopping transformer demanding,i don't trust myselfto do this
Gaetano.
Dangerous voltages are present everyware in our hobby.
No one can ingnore this!☠️
Just keep all rules against the risk of electric shock .
Always use an isolation transformer.
Work in a clean workspace.
Work using one hand,keeping the other hand away.
Never you have to work in a hurry!
No one can ingnore this!☠️
Just keep all rules against the risk of electric shock .
Always use an isolation transformer.
Work in a clean workspace.
Work using one hand,keeping the other hand away.
Never you have to work in a hurry!
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Welcome back Pete! I think a DIY SMPS would be a great project! I'm way too backed up with work to be able to contribute to the project much but I'll definitely be following along. Voltages involved aren't anywhere near what many tube amps are running at so basic common sense should be adequate to keep everyone safe.
Texas Instruments have a number of reference designs for SMPS. They include schematics, pcb layout and gerbers, plus a bom.
Here's one I found - TIDA-01495 could this be used as a starting point ??? it may be possible to modify to provide +/- rails and other O/P voltages. This reference design can provide 24Vdc at 20amps and is regulated unlike the cobra smps which is unregulated.
Features
Here is a search that is already pre-filtered for other SMPS reference designs that may be of interest - TI SMPS Reference Designs
Here's one I found - TIDA-01495 could this be used as a starting point ??? it may be possible to modify to provide +/- rails and other O/P voltages. This reference design can provide 24Vdc at 20amps and is regulated unlike the cobra smps which is unregulated.
Features
- Thin profile < 17mm height for use in space constrained applications with PCB form factor of 185 x 110 mm
- Full load efficiency of >93.3% (230V AC) and >91.1% (115V AC) with peak efficiency of 94.1% (230V AC) and 92% (115V AC) meets the 80+ Platinum standard
- Phase shedding feature in the PFC stage and advanced burst mode feature in the LLC stage enables high efficiency at light load conditions >84% (230V AC) and >82% (115V AC) at 5% load
- ZCS avoidance feature and OVP sensing feature in the LLC controller improves robustness, system protected for over current, short-circuit, and over voltage, ensuring safety
- High power factor > 0.99 and meets PFC regulations & current THD as per IEC 61000-3-2 Class A
- Designed to meet EN55011 Class B conducted emissions standard
Here is a search that is already pre-filtered for other SMPS reference designs that may be of interest - TI SMPS Reference Designs
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Could it be useful for this to feed the audio chain through a DC blocker + EMI filter?
Gaetano.
I looked at Indeglo's TI stuff. Has The PFC and advanced switching controller.
We are going to be forced into going with some semi manufacturers "magic" controllers.
Here are the "magics" I am researching.
https://www.ti.com/lit/ug/tidube1c/...74934&ref_url=https%3A%2F%2Fwww.google.com%2F
The PFC and the "trashing of the AC line" is where most audio noise would occur. If you had a wolverines trafo plugged into
the same outlet (powerstrip) as a "dirty" SMPS (PFC wise) you would see spikes on the legacy toriod.
The output is less critical , it is easy to filter out any ringing of the high/low side mosfets.
Of course , it is better to have little ringing (or IC controlled soft switching) at the output - and then a good passive LC filter.
a better output also increases efficiency. Less harmonics shorted to ground. Cooler devices.
Some PC supplies and many Asian/Ebay off-the-shelf just use barely adequate passive PFC , hoping that the end user does not
approach the the top current ratings. My Seasonic and some of the 300$ + (Cobra) audio supplies are "overkill".
I have seen a trend for (smaller <600w) audio PS's to use certain types of soft-switching that mitigate the pfc issues.
Still learning the "magics". But , having fixed so many ... pretty steep curve !
We are going to be forced into going with some semi manufacturers "magic" controllers.
Here are the "magics" I am researching.
https://www.ti.com/lit/ug/tidube1c/...74934&ref_url=https%3A%2F%2Fwww.google.com%2F
The PFC and the "trashing of the AC line" is where most audio noise would occur. If you had a wolverines trafo plugged into
the same outlet (powerstrip) as a "dirty" SMPS (PFC wise) you would see spikes on the legacy toriod.
The output is less critical , it is easy to filter out any ringing of the high/low side mosfets.
Of course , it is better to have little ringing (or IC controlled soft switching) at the output - and then a good passive LC filter.
a better output also increases efficiency. Less harmonics shorted to ground. Cooler devices.
Some PC supplies and many Asian/Ebay off-the-shelf just use barely adequate passive PFC , hoping that the end user does not
approach the the top current ratings. My Seasonic and some of the 300$ + (Cobra) audio supplies are "overkill".
I have seen a trend for (smaller <600w) audio PS's to use certain types of soft-switching that mitigate the pfc issues.
Still learning the "magics". But , having fixed so many ... pretty steep curve !
Here is how simple we could go , about 30$ group buy arena ...
https://320volt.com/en/audio-amplifier-smps-circuit-ir2153/
Even as the IR2153 is a sound established controller , I would want pfc ,
10A bridge , bigger caps ... etc.
It can be done.
https://320volt.com/en/audio-amplifier-smps-circuit-ir2153/
Even as the IR2153 is a sound established controller , I would want pfc ,
10A bridge , bigger caps ... etc.
It can be done.
Attachments
“Among many resonant converters, the half-bridge LLC-type resonant converter has been the most popular topology for many applications since this topology has many advantages over other topologies; it can regulate the output over wide line and load variations with a relatively small variation of switching frequency, it can achieve zero voltage switching (ZVS) over the entire operating range, and all essential parasitic elements, including junction capacitances of all semi-conductor devices and the leakage inductance of the transformer, are utilized to achieve soft-switching.”
This was a statement that hit home.
PFC becomes much less an issue here, So .. ( series-resonant half bridge topology) it is.
Cool ! DIP-16 no smd.... So L6599 https://www.st.com/resource/en/datasheet/l6599a.pdf
And why not also add PFC because ST makes a resonant pfc controller that communicates with the dc/dc convertor.
https://www.st.com/resource/en/datasheet/l6564h.pdf
The 6564 can shut down the 6599 for brownouts / over-under V . And the 6599 can "communicate" the output load
to the 6564. Turn PFC off for low or no load , and scale to any high loads. quite a PAIR !
OS
This was a statement that hit home.
PFC becomes much less an issue here, So .. ( series-resonant half bridge topology) it is.
Cool ! DIP-16 no smd.... So L6599 https://www.st.com/resource/en/datasheet/l6599a.pdf
And why not also add PFC because ST makes a resonant pfc controller that communicates with the dc/dc convertor.
https://www.st.com/resource/en/datasheet/l6564h.pdf
The 6564 can shut down the 6599 for brownouts / over-under V . And the 6599 can "communicate" the output load
to the 6564. Turn PFC off for low or no load , and scale to any high loads. quite a PAIR !
OS
Attachments
"veteran" is good. Of course we use fast diodes !!! SR is not as critical with soft switching , but we are rectifying 60-100Khz , not 60hz.
I like how ST has the "pair" (PFC - dc/dc) IC's. All the Connex SMPS use 6599 , Hypex uses TI .... many choices , indeed.
"veteran" is also good as "supply chain issues" plague many in the world.
PS - 6599 D = 4th revision "veteran" ... excellent. No bugs !
I like how ST has the "pair" (PFC - dc/dc) IC's. All the Connex SMPS use 6599 , Hypex uses TI .... many choices , indeed.
"veteran" is also good as "supply chain issues" plague many in the world.
PS - 6599 D = 4th revision "veteran" ... excellent. No bugs !
2X30V/300W without the need of rewinding the smps transformer is a good option!
But Thimios , That IR2153 is primitive ! Do I have to design 2 units ? (primitive and advanced).
My 5V led supplies use the 2153's ... not bad after I replace the Chinese caps and fix the heatsinking.
They DO get noisy as they reach rated amps.
With active PFC , they would be acceptable. But if we implement PFC (with added complexity) .. why not go all the
way with the more advanced controller/PFC combo. 6599/6564 combo would be better than most 200$+ offerings.
If we went "anal" with layout and sourcing (premium components) we could have a Wolverine "match".
"Halcro level SMPS" !!
Im going to review the Lab Gruppen SMPS's for inspiration. This is how I designed a most perfect AB amp ... I want a perfect SMPS
to match,
My 5V led supplies use the 2153's ... not bad after I replace the Chinese caps and fix the heatsinking.
They DO get noisy as they reach rated amps.
With active PFC , they would be acceptable. But if we implement PFC (with added complexity) .. why not go all the
way with the more advanced controller/PFC combo. 6599/6564 combo would be better than most 200$+ offerings.
If we went "anal" with layout and sourcing (premium components) we could have a Wolverine "match".
"Halcro level SMPS" !!
Im going to review the Lab Gruppen SMPS's for inspiration. This is how I designed a most perfect AB amp ... I want a perfect SMPS
to match,