UCD 25 watts to 1200 watts using 2 mosfets

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#4,861
Dont use 10 ohm resistance in bootstrap high side . Use lower value instead it limit 1amp though diode.make it 2 amps at 12v. Same with others your low side drive current is .5 amp. Even low. If you want multiple fets more amps. 1 amp for 1 fet atleast. Y u used 47k tied from v+ to bootstraped 12v? The 4.7k resister used to ground fet should be before the buffer too. To ground the bd140 for fater turn off. Also if your ir2110 cannot handle 2 amp,its probably fake. And use snubbers for fets.
 
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#4,862
vishal raju said:
Dont use 10 ohm resistance in bootstrap high side . Use lower value instead it limit 1amp though diode.make it 2 amps at 12v. Same with others your low side drive current is .5 amp. Even low. If you want multiple fets more amps. 1 amp for 1 fet atleast. Y u used 47k tied from v+ to bootstraped 12v? The 4.7k resister used to ground fet should be before the buffer too. To ground the bd140 for fater turn off. Also if your ir2110 cannot handle 2 amp,its probably fake. And use snubbers for fets.
Click to expand...
woow thanks alot for the point outs , kindly draft a small schematic for the values and wattage , of the components you have adviced me on . thanks in advance
 

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#4,863
hi
vishal raju said:
Dont use 10 ohm resistance in bootstrap high side . Use lower value instead it limit 1amp though diode.make it 2 amps at 12v. Same with others your low side drive current is .5 amp. Even low. If you want multiple fets more amps. 1 amp for 1 fet atleast. Y u used 47k tied from v+ to bootstraped 12v? The 4.7k resister used to ground fet should be before the buffer too. To ground the bd140 for fater turn off. Also if your ir2110 cannot handle 2 amp,its probably fake. And use snubbers for fets.
Click to expand...
hi all , i have replaced all the 10ohms resistors with 2.2ohms resistors .the hf noise issue has not improved much .
The other thing i observed is the output temperature has gone up and i need to mount a small heatsink even when testing at idle.
i also added a2.2k resistor at the base buffer to ground respectively but i saw no improvement in noise issues.

the feedback is shown below ,i used a white jumper wire as i did not find space for it in the pcb🙂

the voltage i used was +/-53vlts , output fets are irfp4227 , gate driver transistors are a1027 and c2655 gate drive resistor are 3.9ohms
 

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#4,865
vishal raju said:
Remove r14
Click to expand...
i have removed the r14 resistor and it works normally .

Also i have noted when i remove the rca input jacks from the amp, the amp is very silent.
but when i connect to my laptop the small noise appears , when i unplug the laptops charger , and use the laptops battery the small hf noise reduces .
when the charger is connected to my laptop and i connect mains ground to the amps 0vlts the small hf noise increases lightly instead of being eliminated.

what can i do to improve or to eliminate the small hf noise clearly audible at low volumes.?
 
#4,871
hi all , i am working on a discreet version based on kartinos schematics and fully tested by Wahyu Eko Romadhon https://www.youtube.com/@WahyuEkoRomadhon at his youtube channel .

i wanted to change the layout to my liking 😉🙂🙂

ideas and opinions are highly welcomed .
 

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#4,876
stewin said:
hi all , i am working on a discreet version based on kartinos schematics and fully tested by Wahyu Eko Romadhon https://www.youtube.com/@WahyuEkoRomadhon at his youtube channel .

i wanted to change the layout to my liking 😉🙂🙂

ideas and opinions are highly welcomed .
Click to expand...
hi all ,
it has taken long but by the grace of ADONAI ELOHIM i have managed to complete the discreet version . thanks to wahyu and katrino ,
i managed to add dc offset preset. the testing voltage was +/-51 volts ,i used it as btl config . it is powerful and the fets are cool. note that i have not mounted them on a sink 😁😎 . they ran cool , when i used 1.6ohms load thats when they started to warm. fets used were 4227pbf

output inductor i used 38uh , but it was large. i finally settled to 15uh and it worked great

for the aux 12v supply i used a lm2596 adjustable module , because my smps aux voltage was about 17vlts😇

any ideas and suggestions are welcomed .
have fun all who are in.
 

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#4,877
stewin said:
i have removed the r14 resistor and it works normally .

Also i have noted when i remove the rca input jacks from the amp, the amp is very silent.
but when i connect to my laptop the small noise appears , when i unplug the laptops charger , and use the laptops battery the small hf noise reduces .
when the charger is connected to my laptop and i connect mains ground to the amps 0vlts the small hf noise increases lightly instead of being eliminated.

what can i do to improve or to eliminate the small hf noise clearly audible at low volumes.?
Click to expand...
Improve PSRR
 
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#4,879
stewin said:
hi all ,
it has taken long but by the grace of ADONAI ELOHIM i have managed to complete the discreet version . thanks to wahyu and katrino ,
i managed to add dc offset preset. the testing voltage was +/-51 volts ,i used it as btl config . it is powerful and the fets are cool. note that i have not mounted them on a sink 😁😎 . they ran cool , when i used 1.6ohms load thats when they started to warm. fets used were 4227pbf

output inductor i used 38uh , but it was large. i finally settled to 15uh and it worked great

for the aux 12v supply i used a lm2596 adjustable module , because my smps aux voltage was about 17vlts😇

any ideas and suggestions are welcomed .
have fun all who are in.
Click to expand...
one with relay and oc , dco protection loading , for insane power just make two of these and drive them in btl mode .
have fun all
 

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