It is not useless, but requires fan. If it was useless then all motherboards are useless heatsinks
Well, you should have a look for the main thermal path. Heatsinks on plastic are useless. The main thermal path on this chips is via the exposed pad on the bottom. As for the mainboards, those chips are coupled via direct substrate or heatspreader or sometimes top exposed pad.
Well, you should have a look for the main thermal path. Heatsinks on plastic are useless. The main thermal path on this chips is via the exposed pad on the bottom. As for the mainboards, those chips are coupled via direct substrate or heatspreader or sometimes top exposed pad.
I just had a look at the chip itself, and you are absolutely right. The cooling should be build into the PCB. I once had a 2x200 watt 8 ohm class d done this way. It's amazing to fire up such an powerfull amplifier without heatsinks
Well then, got my new design ready and running.
Here: http://www.diyaudio.com/forums/class-d/87913-class-d-amp-photo-gallery-81.html#post3716821
Here: http://www.diyaudio.com/forums/class-d/87913-class-d-amp-photo-gallery-81.html#post3716821
These are in use by the Gilderfluke company
Gilderfluke uses these in the SD-25. We have a bunch and they work reasonably well.
https://www.gilderfluke.com/index.php?main_page=product_info&products_id=35
Gilderfluke uses these in the SD-25. We have a bunch and they work reasonably well.
https://www.gilderfluke.com/index.php?main_page=product_info&products_id=35
Suitable crossover for the MAX9709 boards. (Same shape)
Linkwitz-Riley configuration, x-over at 200Hz, single ended configuration.
Input:
3.5mm jack pre-potentiometer
3.5mm jack bypassed potentiometer
4x pinheader post-potentiometer
Output:
3.5mm jack Highpass Stereo
3.5mm jack Lowpass Mono+Mono with adjustable gain
4x pinheader Highpass Stereo
4x pinheader Lowpass Mono+Mono with adjustable gain
Coupling caps are either MKS2 (Wima) or 1206 X7R ceramics.
aktive 2.1 Crossover/Frequenzweiche mit MAX4478 - #360customs
Linkwitz-Riley configuration, x-over at 200Hz, single ended configuration.
Input:
3.5mm jack pre-potentiometer
3.5mm jack bypassed potentiometer
4x pinheader post-potentiometer
Output:
3.5mm jack Highpass Stereo
3.5mm jack Lowpass Mono+Mono with adjustable gain
4x pinheader Highpass Stereo
4x pinheader Lowpass Mono+Mono with adjustable gain
Coupling caps are either MKS2 (Wima) or 1206 X7R ceramics.
aktive 2.1 Crossover/Frequenzweiche mit MAX4478 - #360customs
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