full differential UcD modulator with extra integrator

[Sous]

modulator

 

[diyaudnut]

L chanel: sound card line out=>amplifier =>divider 1/10=>sound card line in
R chanel: sound card line out=>sound card line in (we call it a through channel measurement)

ah that makes sense

 

[ledsscp7]

Sous, nice job!

 

[Sous]

thanks

 

[odnaizutra]

Very nice job.

 

[Sous]

Very nice job.

Thanks!
just finished testing the first sample

THD on load 3.3 Ohm. PS - 50Hz 120W transformer with 2x30V
winding.

-6dB=130W (135W-amp clipping)


scale in decibels - the input level of the audio card

 

[Kuba_eM]

Hi Sous,
This modulator is very interesting project, good job!
I would like to ask you for sharing us schematic of output stage module HB rev 1_021. Could you post it, please?
Thank, you.

 

[Sous]

Thanks, Kuba_еМ.
details here: Óñèëèòåëüíûé ìîäóëü ïî ìîòèâàì ncore

 

[Kuba_eM]

Thank you Sous, it seems that I need to renew the knowledge of the Russian language 🙂 No, in real earnest it is all clear, I like projects from this forum.

 

[Sous]

Thank you Sous, it seems that I need to renew the knowledge of the Russian language 🙂 No, in real earnest it is all clear, I like projects from this forum.

))

C'est La Vie.
In the first post there inverter circuit are you looking for

 

[bimbla]

Fully Differential UCD Modulator

slightly modified the concept
based on ncore white paper.

Hello Sous,

Thanks for sharing the circuit. Is this the one you have implemented in your final version? Kindly help me understand the function of the circuit based around the matched transistors pairs BCV6x.

Thanks in advance!!

 

[bimbla]

Fully Differential UCD Modulator

I guess the circuit around DCV6x acts like a limiter. But I would still like your analysis since you are the designer.

Also, in the full bridge implementation, say, with single supply, will the modulator keep the DC at the output in check or do we need to implement a DC servo additionally.

Thanks in advance!!

 

[Sous]

The transistor circuit turns off the integrator closely to the clipping.

The bridge has not yet been implemented, because I do not know that circuit needs servos, I think that is not necessary.

 

[bimbla]

Fully Differential UCD Modulator

Hello Sous,

Thank-you for your early reply. I will attempt to make your modulator.
This is going to be a slow paced project. I will post my results here.

Thanks again!!

 

[Pafi]

Sous,

If the bridge is not ready, then how did you test the modulator?

Could you give me a link to the hypex tech paper U used?

 

[Sous]

used to test the half-bridge inverter .
As I said, the modulator do not care what the output stage is connected to it

Something that may be found in the ncore white paper
https://www.google.com.ua/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiCwKeGj6DOAhUJQZoKHT-bDhIQFggcMAA&url=http%3A%2F%2Fwww.hypex.nl%2Fdocs%2Fpapers%2Fncore%2520wp.pdf&usg=AFQjCNG8_9RQTfW-Ajp_RhV8ygcr7Za1PQ&sig2=2gajYYohh4m-q9XNu7f0Lg
Respected Bruno P. spoke clearly enough about ncore

Аnd of course in the service manual NAD m22 (Ncore400ОЕМ)

 

[Sous]

I must say that, nevertheless, failed to get the values that are achieved in the original ncore.
The circuit layout is very critical to the power section of the inverter. It is advisable to do a 4-layer board. And the dynamic dead time control is desirable
However, it turns out a good amp for home use, THD + noise 1-15 watts less than 0.0015%

 

[Pafi]

Used to test the half-bridge inverter. As I said, the modulator do not care what the output stage is connected to it

I don't know if you said or not, but what does it mean? The modulator doesn't have an opinion of course, and will work, but do you really think output stage topology (and details) doesn't affect overall quality?

Thanks for the link, however I didnt find the relevant connection between that doc and your schematic yet.

 

[Pafi]

Also, in the full bridge implementation, say, with single supply, will the modulator keep the DC at the output in check or do we need to implement a DC servo additionally.

In differential mode the modulator ensures very low DC. In common mode the voltage will be exactly half way between power rails, and there is no way to change it.

I'm working on a really differential self-oscillating amp, but in that you can set common mode voltage independently (however the optimal value is almost in the middle).

 

[Sous]

I don't know if you said or not, but what does it mean? The modulator doesn't have an opinion of course, and will work, but do you really think output stage topology (and details) doesn't affect overall quality?

Thanks for the link, however I didnt find the relevant connection between that doc and your schematic yet.

my friend has implemented a similar scheme without servo, products launched in the series. full bridge TAS5162 and similar type MDR
Your statement about the need for servo easily check in the simulator.
Of course, the experiment will show who was right. However, the simulator is not deceived me

Thanks for the link, however I didnt find the relevant connection between that doc and your schematic yet.

Well, if you can not find the similarity, what can I do?