My design L20D IRS2092+IRFI4020H 200W8R

Is there any way to make the L20D/L25D suitable for lower voltages, e.g. between +/- 35 and 50VDC?

LJM's L15D design discussed here: http://www.diyaudio.com/forums/class-d/180625-irs2092-iraudamp7s-irfi4019.html can use +/- 50VDC. See page 37 of he reference document IRAUDAMP7S-150 for the component differences between the models (L15D = AMP7S-150, L20D = AMP7S-200). A few component changes are required to use lower voltage power supplies (ala AMP7S-60 and AMP7S-55)
 
Hi LJM,

What's the inductor rating & value compare with L15 & L20?

Instead using 2 4020H , you can use 2 4227 (without buffer) ?

4227 can drive 4 ohm at high voltage or 2 ohm at low voltage.

The inductor is the same for the L15 and L20, 220 uH, 13A..

If you tried using the 4227, to drive higher current into 2 ohms, you'd have to at least switch the inductor to a 7G31A-220M-R which has a 31A rating.. (notwithstanding, you'd probably be doubling the cost of the modules with those two component changes alone (single unit price is 2x for the 4227 and 4x for the 7G31A))

LJM would have to comment on what other changes would be required..
 
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The inductor is the same for the L15 and L20, 220 uH, 13A..

LJM would have to comment on what other changes would be required..

If I remember correctly, 4020 output is 9 amp, using 2 should be able to output at 18amp ?
Can the inductor handle 4 ohm speaker?

But again, LJM specifically said it's 350 watt for 4 ohm.
I guess the inductor is the limitation and costing as well.

:D cheers ..
 
If I remember correctly, 4020 output is 9 amp, using 2 should be able to output at 18amp ?
Can the inductor handle 4 ohm speaker?

But again, LJM specifically said it's 350 watt for 4 ohm.
I guess the inductor is the limitation and costing as well.

:D cheers ..


Yes, I try various low cost but they don't let me inductance satisfaction.

I have seven G31A the inductance, it's expensive, and need 1 K number above just have the order.

It made him feel is not effective. I don't know the actual use of whether there is a need to output so big of current.

I seldom see less than 4 ohm speakers. You feel really necessary? Maybe in small power may not better listen to sound.

:rolleyes:
 
Thanks for posting this info, LJM. I am building a modified Linkwitz Pluto with a Peerless Tymphany 890983 'tweeter' as I don't like the resonance in the Aura 'tweeter'.

I have bought a miniDSP board instead of the Linkwitz analog filters, it works well. I am looking for some amplifiers to use to drive the Seas L16RN. They are rated at 80W sinewave and 250 Watts peak IEC longterm noise. I had chosen to use the (bridged) TDA8920BTH boards from Yuanjing, but they oscillate at 50KHz rather badly, and I can't dampen it by changing the output inductors. Must be a grounding problem. So it would seem that I should invest in a higher voltage transformer and a pair of L20 boards :) I am happy with the TDA7293 boards I bought for the tweeters. Power for the 890983 is somewhere between 7W and 60W, depending on which Peerless data sheet revision you are reading (v1 or v2) so the TDA7293 has plenty of power and looks really nice and clean on my oscilloscope, just what I need for a tweeter, I think :)

So congratulations on getting the L20 stable, I will order a pair and let you know what I think.

Happy Summer -- I was in Dalian in April and May, and Shanghai in June, but I do remember the heat when I spent August in Chengdu during 2009 -- it is very hot indeed. Much more pleasant here in California, I think :) We don't even need air-conditioning (just heating for winter). Thanks again for the help...


My English is not good, the software seems a bit faster than my translation.

But the software is always miss the lower content.

So you come to chengdu's accident. Here is a climate change is very obvious place.
:superman: