hello, I have a 700w amp into 4 ohms with mosfet irs2092 and irfb23n20d.
Often, high volume goes into protection mode and reset.
If you want to replace the MOSFET with two IRFB 38n20d or with IRFB 4227 would benefit?
would warm less?
could not go into protection?
replacement covers only the mosfet?
Often, high volume goes into protection mode and reset.
If you want to replace the MOSFET with two IRFB 38n20d or with IRFB 4227 would benefit?
would warm less?
could not go into protection?
replacement covers only the mosfet?
Firstly I would check the power supply rails for stability as that would affect the centre point and make the output stage unstable.
If it is OK then check the dead time with a scope, make sure at high levels it is not varying too wildly.
Changing the output fets for larger ones will not keep it any cooler, the heat is caused by the switching time constant from the IRS2092. Inserting a network in the drive, may speed the time up slightly. What is your base frequency and what is the output inductors inductance?
If it is OK then check the dead time with a scope, make sure at high levels it is not varying too wildly.
Changing the output fets for larger ones will not keep it any cooler, the heat is caused by the switching time constant from the IRS2092. Inserting a network in the drive, may speed the time up slightly. What is your base frequency and what is the output inductors inductance?
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the problem of autoreset (protection on veri high volume) is on 4 ohm.
With 8 ohm no autoreset.
You will need to adjust over current detect circuits.
There is an upper and lower one to adjust.
The upper one should have a potential divider on it.
http://media.digikey.com/photos/rdl/iraudamp7s_150_schematic_full.png
shcematic is around this.....if i want disable the detect ovre current circuits is a problem?
shcematic is around this.....if i want disable the detect ovre current circuits is a problem?
I think you are to buy the products of China's production of unqualified false advertising.
23 n20d does not suit to use. Remember correctly its radiator is very small.
It's normal power estimation is 10-50 w. Nominal 700 w just to deceive consumers.
I hate China with these products.
In addition to power, its distortion is one hundred times larger than the IRFI4020.
The designer's level is very bad
If you don't believe, you can find a analog amplifier, 50 w power.
It is certainly better than your digital power amplifier, 700 w, and greater power. In China's production of digital power amplifier, 99% has no real power test.
Labeled power are written at random. 700 w if can output 70 w. Your luck is very good.
23 n20d does not suit to use. Remember correctly its radiator is very small.
It's normal power estimation is 10-50 w. Nominal 700 w just to deceive consumers.
I hate China with these products.
In addition to power, its distortion is one hundred times larger than the IRFI4020.
The designer's level is very bad
If you don't believe, you can find a analog amplifier, 50 w power.
It is certainly better than your digital power amplifier, 700 w, and greater power. In China's production of digital power amplifier, 99% has no real power test.
Labeled power are written at random. 700 w if can output 70 w. Your luck is very good.
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Believe me, you go to buy a set of the cheapest LM4766T, as long as the correct design of power amplifier.
About less than $10.
Use a 24-0-24 v AC transformer, you will find.
In actual use, LM4766T both in 35 watt, sound quality, power, stability, and reliability,
Are far more than you so-called digital power amplifier, 700 w.
Even power consumption and heat also is very small.
About less than $10.
Use a 24-0-24 v AC transformer, you will find.
In actual use, LM4766T both in 35 watt, sound quality, power, stability, and reliability,
Are far more than you so-called digital power amplifier, 700 w.
Even power consumption and heat also is very small.
I am not sure what ljm is talking about! I have one of these modules, does yours have speaker protection ? In any case your load impedance may be dipping a lot below 4R at certain frequencies, the other possibility is your power supply, have you checked the auxiliary rails always remain in regulation, that will instantly make it protect, maybe you didn't set there resistors according to instructions. Next up use an oscillator and moderate power to try and localize the problem to a given frequency then you can look at things more carefully anyway there's nothing basically wrong with the amp just needs care in use. Ohh one other thing, it could be thermal protection in the IRS2092, make sure the sink is properly attached using THERMAL PASTE not stupid white silicon!! One other potential issue you may be suffering is BUS PUMPING check your main voltage rails are not pumping up excessively this also is possible given your symptoms.
anyway there's nothing basically wrong with the amp just needs care in use. Ohh one other thing, it could be thermal protection in the IRS2092, make sure the sink is properly attached using THERMAL PASTE not stupid white silicon!! One other potential issue you may be suffering is BUS PUMPING check your main voltage rails are not pumping up excessively this also is possible given your symptoms.
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