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The IRS2092 datasheet shows a 4 ohm load circuit (see image below).

I want to check whether MOSFETs can be paralleled to support low impedance of 2 ohms, instead of 4 ohms as shown. Can anyone please let me know whether it is feasible?

The MOSFETs I plan to use are IRF540.

Typical Application Circuit

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    \$\begingroup\$ At a first glance it should work. Read the AN "Paralleling Of Power MOSFETs For Higher Power Output" for the gory details and calculations involved. Also the output filter will need a tune up \$\endgroup\$
    – Lorenzo Marcantonio
    Commented Mar 12, 2021 at 9:02
  • \$\begingroup\$ Comparing the application specific (small power, Id < 10A audio etc) IRF6645 to general purpose high power (Id > 30A) amplification/switching IRF540 datasheets on the general parameters Vds, Id, Vgs(th) etc, I found IRF6645 is smaller in size, but also smaller in power, better thermal performance. So if Infeion specifies that IRF6645 can do the audio amplification job, it is very likely the IRF540N can also do the job at much higher power, but also much worst audio performance. \$\endgroup\$
    – tlfong01
    Commented Mar 12, 2021 at 9:17
  • \$\begingroup\$ And in case you are doing trials and errors, I would recommend IRL540N which should preform better than IRF540N. Also the following might help: How to choose MOSFETs for Class D amplifiers - By Jorge Cerezo, International Rectifier 02.14.2006 eetimes.com/how-to-choose-mosfets-for-class-d-amplifiers/# \$\endgroup\$
    – tlfong01
    Commented Mar 12, 2021 at 12:37
  • \$\begingroup\$ Wonderfuliot, please take the 2 minute tour to understand what motivates people to give free advice on this site. \$\endgroup\$
    – Andy aka
    Commented Mar 21, 2021 at 16:13

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It will be able to drive parallel MOSFETs because they are being used in their triode region but, take into account what the application note says here: -

enter image description here

So, if you choose two parallel MOSFETs you should ensure that the total combined gate charge does not exceed the limitations implied in the top paragraph.

You might also be sensible to track down what AN-1070 is telling you: -

enter image description here

Enjoy the read.

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