Hi I am a long time in the forum but only read from here I learned a lot of things that interest me. Excuse me for bad English but use a translator. I made my first class D amplifier - IRS2092 + IRFB4227, but I have a problem. I can not get to work on oscillatory frequency higher than 190-200Khz. Protection is activated and turn off output. Attached the schematic on which work with an adjustment of the elements. What may be a problem in your opinion? Dead time of transistors is 45 ns and 65ns tried the effect is the same. Output choke is Mikrometal T106-2 - 40 turn 22uH. Gate resistors is - 10 ohms!
Thanks for your help!
Thanks for your help!
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Change 4227 for light - IRFB4615 etc.
IRFB4227 big gate charge - it is more than time for opening
IRFB4227 big gate charge - it is more than time for opening
use max dead time settings, I think it is 105ns
check that your overcurrent settings are "high", since those fets will handle the current just fine.
when does amp turn off, when you want higher then 200k freq.?
do some measurements, tell me what is the voltage between pin 12 and 10
also, does IRS have +/-5.6v at all times on its supply pins?
on my board R18 is not 0R!
nice looking amp, great job!!
check that your overcurrent settings are "high", since those fets will handle the current just fine.
when does amp turn off, when you want higher then 200k freq.?
do some measurements, tell me what is the voltage between pin 12 and 10
also, does IRS have +/-5.6v at all times on its supply pins?
on my board R18 is not 0R!
nice looking amp, great job!!
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maybe yes, I get 470kHz with no problems with irfp4227, but I have gate buffers, which helps a lot
I tried the IRS2092 + IRFB4227 combination and added a totem pole gate driver because for my application, the gate drive current from the IRS2092 was too small to quickly turn on the IRFB4227. Gate rise time was long (>500uS). With drivers, rise time could be 100nS with 4.7R gate resistor.
I've read posts indicated some members have used the combination without the gate drivers but for my requirements, they were necessary especially with higher switching frequencies.
I've read posts indicated some members have used the combination without the gate drivers but for my requirements, they were necessary especially with higher switching frequencies.
Voltage of 12 volts has always there. When stopping output of the amplifier, voltage 12.1 volts does not disappear!
I have no problems with 4227 and 200KHz.
I did try a faster osc and then the 2092 starts to get warm as if it is struggling a bit so I went back to 200KHz.
My pcb also does drive four 4227 but for that I also have an option for a tc4420 which can be linked in or out depending how many output transistors I use.
I did try a faster osc and then the 2092 starts to get warm as if it is struggling a bit so I went back to 200KHz.
My pcb also does drive four 4227 but for that I also have an option for a tc4420 which can be linked in or out depending how many output transistors I use.
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One problem I had with my pcb was glitches on the 12 volt rail causing clicks on the audio.
I had to decouple the regulator and right next to the 2092 with 10uf.
From here what do you think the problem is large - gate charge. Did I understand? You should try option with driver integrated circuit of the gate. What do you think for these two transistors:
IRFB23N20D
FDP33N25
in this case will do a job without a driver scheme?
Thanks and best regards!
IRFB23N20D
FDP33N25
in this case will do a job without a driver scheme?
Thanks and best regards!
Put 1uF-2uF CERAMIC caps directly on the IRS2092 pins: between pins 10 and 12, between pins 13 and 15. For CP5 and CP6 use tantalum capacitors. I think this will help a lot 😉
Thanks for the replies, I changed two capacitors C5 and C6 with tantalum and placed them parallel the ceramic 1uf, tried and dead time 105 us, I made changes the resistors for short circuit protection - no effect. As I try to increase the frequency above 200 kHz amplifier turn off! Any other ideas? I will replace transistors with IRFB4620 and see what will be the effect!
Thanks and best regards!
Thanks and best regards!
Did you placed the ceramic caps directly on the IRS2092 pins? They must be as close as possible to the chip.
Hello I have a project progress. While arrive IRBF4620, tried to IRFB23n20. Already amplifier operates at 400 kHz with 65 ns dead time. As a result I have with the new transistors will write.
Yes but no effect! Thanks!
Greetings and thanks for the help!
Yes but no effect! Thanks!
Greetings and thanks for the help!
You could try the irfb4227 with a driver IC if you want higher power out.
TC4420 is a good IC. In fact you could drive two pairs of 4227 with that IC.
I'll try option two transistor - PNP and NPN (fzt653 and fzt 753), as in IRAUDAMP9. So it's easier and comfortable but also occupies less space, keeps short-circuit protection. I think so I can reach 400 - 450 kHz, 45-65 ns dead time, transistor IRFB4227. I'll try and write the result! Do you think will have any effect?
Thanks and best regards!
Thanks and best regards!
Hello I tried to IRFB4620, of transistors tested so far this is the best - 500KHz carrier frequency and 45ns dead time! In your resistor R114 in the scheme of the IR, can be reduced in order to better, stabilize the 15 volts for the lower transistor? In other transistors <gate charge that much voltage drop. I've seen schemes without the resistor!
My experience with drivers transistors failed! Score lamentable!
Thanks and Greetings!
My experience with drivers transistors failed! Score lamentable!
Thanks and Greetings!
Do you have the schematics on how 2092 drive 4227 without any buffer?
What's advantage of having no buffer and with buffer?
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