Curious whether any IRS2092 designer/builders see any real-world advantage to using the (slightly better on paper) IRFI4212H in place of the IRFI4019H?
IRFI4212H is rated at higher current over the IRFI4019H. I'd prefer the IRFI4212 but the real question is: What is your supply voltage, output power you are trying to achieve and what speaker Z are you driving? Neither one is quite the right part for 4 ohms. 8 ohms should be OK with the 4212H. The IR datasheets mention what power out you can expect from these parts, I think.
Yes, higher current, but also switches faster, which all else equal (and no parasitics) should allow lower di/dt losses and lower dead time without shoot through.
Supply voltage, output power and load impedance are not issues, as the intended use is in "active" devices with a single driver load on each amp.
Supply voltage is an issue. Why? Breakdown V and max. current. Typically, you should spec. the absolute maximum current thru a FET to be 50% of the calalog max. rating. So, you need to know the max. supply voltage and the minimum Z of the speaker, plus the filter inductor min. resistance as well to get worst case current.
Overall the IRFI4212 is the "better" fet. Lower Ciss and Gg than the 4019. Easier to drive faster.....all things considered. But these are twin fets in one 5 pin package. Very convenient but if you need more current that 11 amps WC, you will have to go to seperate packaged fets.
The IRFI4212 is sort of lack luster in the Rdson and power dissipation areas. Only 18 Watts and there are plenty of fets with much lower Rdson, which impacts power dissipation when conducting.
Overall the IRFI4212 is the "better" fet. Lower Ciss and Gg than the 4019. Easier to drive faster.....all things considered. But these are twin fets in one 5 pin package. Very convenient but if you need more current that 11 amps WC, you will have to go to seperate packaged fets.
The IRFI4212 is sort of lack luster in the Rdson and power dissipation areas. Only 18 Watts and there are plenty of fets with much lower Rdson, which impacts power dissipation when conducting.
No, really, it isn't.
In the intended application, and comparing the two devices, either is easily capable of supplying the necessary current or supporting the necessary voltage with more than adequate margins.And there was, and is, the question. Does the "better" translate into better performance, audible or measurable, in a real-world amplifier.
OK. Here are "better" FETs than the 4212 or 4019.
Look at the EPC2001 or EPC1005. They are GaNFETS. Faster, Rdson on order of magnitude lower at 7 milliohms and double the current capability at 25 amps. Hands down superior to the ones you have chosen. Can't handle the package? Sorry. That's the price of admission to having to have the BEST.
Engineering is all about compromise and living with the choices we have to make. We have to know when good enough IS good enough.
Any Class D amplifier has to minimize dead time in order to make the lowest distortion. If dead time is too short, shot through occurs and the FETs generally get hot - maybe too hot and die. Lower Rdson makes it easier to dissipate the power due to I^2 * R losses, inherent in ALL FETs. Most FETs are fast enough for a Class D amplifier but faster is better, if you can get it. You can have the best FETs and still muck up the sound of amplifier if you choose the wrong output filter components.
Look at the EPC2001 or EPC1005. They are GaNFETS. Faster, Rdson on order of magnitude lower at 7 milliohms and double the current capability at 25 amps. Hands down superior to the ones you have chosen. Can't handle the package? Sorry. That's the price of admission to having to have the BEST.
Engineering is all about compromise and living with the choices we have to make. We have to know when good enough IS good enough.
Any Class D amplifier has to minimize dead time in order to make the lowest distortion. If dead time is too short, shot through occurs and the FETs generally get hot - maybe too hot and die. Lower Rdson makes it easier to dissipate the power due to I^2 * R losses, inherent in ALL FETs. Most FETs are fast enough for a Class D amplifier but faster is better, if you can get it. You can have the best FETs and still muck up the sound of amplifier if you choose the wrong output filter components.
If Rdson means resistance in the "on" state, that's true, but more to the point is that I^2 * R are less, right?
Would this be reflected in a significant (say, 20% or more) reduction in idle consumption?
If you can't answer the question asked just say so . . . don't prattle on with pointless nonsense.
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