to nmos and hilli.
yes it is a eletrolytic 100uf/35v, i am not a expert in d-amps so i dont know if igbt is better in this amp, i´ve use irfp4227, but one thing is very very importment, it´s a good groundplane, i´ve have made 6 different pcb´s before the amp i have now and all the others have dc and lot of noise on output, the final amp i´ve have now have a dual layer pcb with one big groundplane on top of the pcb, i have read and read about d-amps construction to learn about d-amps, even then i have finished my final amp there was still a little noise until i read a article by bruno portsey that if the induktor are upright on pcb is it bad, so i try laying down the induktor on pcb and the rest of noise was gone, my amp are basicly the same as the original but i´ve have made some changes, i have seperated the +-3v to lm311 and seperated 12v to ir2110, the inductor is a amidon T130-2 (18uh) output capasitor 1uf the 10k in fb is changed to 33k and the 330pf in fb is now 100pf so the switch freq is around 250khz, my supply voltage is +-68v, i have onboard dc protection (upc1237) and my supply is a smps based on irs2153.
i use 4 of this amp to drive 4 subwoofers (18") in my mobile disco and they are so great. i have plan to make a couple of these amp to the topspeakers to because they are sounding great in my ear.
yes it is a eletrolytic 100uf/35v, i am not a expert in d-amps so i dont know if igbt is better in this amp, i´ve use irfp4227, but one thing is very very importment, it´s a good groundplane, i´ve have made 6 different pcb´s before the amp i have now and all the others have dc and lot of noise on output, the final amp i´ve have now have a dual layer pcb with one big groundplane on top of the pcb, i have read and read about d-amps construction to learn about d-amps, even then i have finished my final amp there was still a little noise until i read a article by bruno portsey that if the induktor are upright on pcb is it bad, so i try laying down the induktor on pcb and the rest of noise was gone, my amp are basicly the same as the original but i´ve have made some changes, i have seperated the +-3v to lm311 and seperated 12v to ir2110, the inductor is a amidon T130-2 (18uh) output capasitor 1uf the 10k in fb is changed to 33k and the 330pf in fb is now 100pf so the switch freq is around 250khz, my supply voltage is +-68v, i have onboard dc protection (upc1237) and my supply is a smps based on irs2153.
i use 4 of this amp to drive 4 subwoofers (18") in my mobile disco and they are so great. i have plan to make a couple of these amp to the topspeakers to because they are sounding great in my ear.
hi guys i found multiple of these fet transistors on an old ups mother board . rds is low ( PHP27NQ10T ) SOT404 (D2PAK) can these be used as outputs if i use +/- 45vlts and bridge it at 4 ohms? steve
I've used the similar PHP29N08T very successfully in a bridged UCD amp, running from a single +55V rail. Your parts have a somewhat higher gate charge, but looking at the data sheet, they should work very well. Are you intending to bypass the D-S internal diode with some 100V Schottkies?
no i don't know very much on the technical except what i have learned here at diyaudio. but intend to use it that way without adding any thing.
Hi, I'm new here and I ned sum help. I have tried 2 simulate the amplifier but I'm gettin incorrect output. My input sinewave is 1V 1kHz, bt my output wave is 10uV, can any1 guide me plz?I'm also new to LTspice.TQ.
Uploaded with ImageShack.us
Uploaded with ImageShack.us
An externally hosted image should be here but it was not working when we last tested it.
Uploaded with ImageShack.us
An externally hosted image should be here but it was not working when we last tested it.
Uploaded with ImageShack.us
I was working full bridge desing and my expiriance was good. My only problem was weak transformer for power supplays. I used two this amplifiers and Bridge adapter to invert sine wawe ( one + one -). My PSU was +-50V and load was 8 ohms and later 4 ohms. Matematicly on 4 ohms i shuld to get 1200W but music is not a loud, only double of one chanel, but my PSU transformer was 500W. I think this is a only reason.
On this url I found bridge adapter. Input is mono signal and its has two ouptus one positive sine wawe and second negative (180 deegres invert sine wawe).
Bridging Adapter For Power Amps
On this url I found bridge adapter. Input is mono signal and its has two ouptus one positive sine wawe and second negative (180 deegres invert sine wawe).
Bridging Adapter For Power Amps
try this one
if you put signal on both channels it is driven each channel on the opposite phase so no need of switches or extra out of phase circuit. i've tried add zero or gnd on the whole board to reduce noise. cheers
if you put signal on both channels it is driven each channel on the opposite phase so no need of switches or extra out of phase circuit. i've tried add zero or gnd on the whole board to reduce noise. cheers
if you have access to double sided you can also add gnd /0vlts to the top side to futher on noise reduction
i would appreciate any comments or improvements 🙂 🙂 😀 😀
i would appreciate any comments or improvements 🙂 🙂 😀 😀
please check this russian UCD Bridge AMP
there is after LM311 a [SIZE=-1]Quadruple 2-Input Positive-NAND Gates [/SIZE] SN74AC00D IC for Phase invert....and rest of schematic looks like ours
is this a better solution for bridging with less devices and lower component count ?
have not so much experience
Last edited:
If they are to make their own PCB's, should take into account the changes that have been discussed since the beginning of the theme.
Have already spoken of them, most are of this forum, where users with extensive knowledge of the subject. It is to be considered.
In the forum came from the schema (Foros De Electrónica.com) there is a lot more info on the setup and other considerations. The latter was the DC offset correction of the amplifier has the output.
Amplificador HighEnd Clase D de 25W a 1250Wrms sólo con 2 mosfets N - Página 55
http://www.forosdeelectronica.com/f...olo-2-mosfets-n-24854/index55.html#post477281
All this info is to improve the design.
Greetings!
PS: The information is in Spanish
Have already spoken of them, most are of this forum, where users with extensive knowledge of the subject. It is to be considered.
In the forum came from the schema (Foros De Electrónica.com) there is a lot more info on the setup and other considerations. The latter was the DC offset correction of the amplifier has the output.
Amplificador HighEnd Clase D de 25W a 1250Wrms sólo con 2 mosfets N - Página 55
http://www.forosdeelectronica.com/f...olo-2-mosfets-n-24854/index55.html#post477281
All this info is to improve the design.
Greetings!
PS: The information is in Spanish
Last edited:
Do they talk about the ordinary correction of the comparator, and decreasing it's propagation delay?
I am having problems with the normal connection (taking feedback to In-, connecting comparator pin 1 to gnd, and taking output from pin 7, whiele connecting it to +3V with 470r), oscillation does not start, so I need to redesign the feedback.
Tekko did this previously at POST #411, but I dont know his component values. He said it worked, and improved the performance.
In the words of the author. There is another way to adjust the offset without the loss of speed that is usable in this LM311: Harnessing the same offset current comparator to adjust the amplifier output offset. It makes a very simple way: At the point where they join the resistance R7, R2 and C1, cutting the connection to the leg 2 of the comparator, and join it back, but through a 47k variable resistor (multi-turn potentiometer). Adjusting smoothly, can compensate the offset without the problem of loss of fidelity that is the other method. To take into account before designing their own PCB's
Tacatomon:
I don't think so DC offset is a problem with this design. I have less than 50mV. And If somebody has it, there are lot of ways to cancel it.
But any of you tried the normal connection of the comparator? This way it has >1000ns propagation delay. The normal connection has 200ns. The original schematic had a switching freq of about 120-150kHz, very SLOW! With this high prop delay it is difficult to get it over 2-300kHz.
I don't think so DC offset is a problem with this design. I have less than 50mV. And If somebody has it, there are lot of ways to cancel it.
But any of you tried the normal connection of the comparator? This way it has >1000ns propagation delay. The normal connection has 200ns. The original schematic had a switching freq of about 120-150kHz, very SLOW! With this high prop delay it is difficult to get it over 2-300kHz.
Well, not to be, but in all the amplifiers I've done have been presented to the output DC. With +-50VDC around 500mVDC and a +-85VDC 1.5VDC ... That's bad. And for the quality of the components that use should not be. The method proposed by the author does not alter the sound quality of the amplifier and corrects the problem. At least some colleagues have done small tests and have improved the DC output. As yet I have continued with the project but soon hope to be with that. Sorry if I do not quite understand in my writing. Using a translator is not quite perfect. But I understand perfectly.
An other simple method to kill DC offset is by connecting a 10-22uF cap in series with R7 to ground.
But I still haven't got no answer for my question. Do anybody on that forum tried the normal connecting of the comparator? I cannot speak spanish, so I could not tell from that forum.
But I still haven't got no answer for my question. Do anybody on that forum tried the normal connecting of the comparator? I cannot speak spanish, so I could not tell from that forum.