Class D 75W 700kHz

This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I developed and designed class D power amplifier

700 KHZ sampling frequency, no fan blowing, no radiator, calm work

45 mm long, 45 mm wide and 30 mm high


  • 75W尺寸 45X45mm配电源一起出.jpg
    75W尺寸 45X45mm配电源一起出.jpg
    87.3 KB · Views: 717
Impressive. It leaves me with a few questions:
You have two nice output filter chokes and one rather small power supply decoupling capacitor. Are the filter capacitors ceramic SMD or foil? It must be a mono amplifier operating in BTL configuration. I would expect 6-7 board connection terminals (in - eventually balanced, out and supply) but I see 9?
Clearly you have most components on the rear side which we do not see. Would it be possible to give us a look at that side as well? You use a 700KHz carrier frequency which is in the high end. 700KHz carrier and 75W will normally necessitate a small heatsink. Do you use a heatsink?
75W is in which impedance?
At which point this is DIY without any more informations, photos or schematics? :geezer:

The 4x4.5-inch active column uses two 75W class D amplifiers.

The 4x4 "active column uses a 75W class D amplifier.

The power supply can work at ac85v-ac265v 50Hz 60Hz

I have worked steadily for more than 2 years since DIY.

No fans, no radiators.


  • 75W.jpg
    57.9 KB · Views: 456
  • 4X4.5寸有源音柱模块.jpg
    71.9 KB · Views: 449
  • 4X4.5寸有源音柱内部.jpg
    181.4 KB · Views: 443
  • 4X4寸有源音柱.jpg
    834.8 KB · Views: 404
  • 4X4寸有源音柱外观.jpg
    444.9 KB · Views: 373
I don´t see the point to show such a primitive construction any school kid could do on a week end, out of cheap, crappy China parts. This is a HIFI forum, not an advertising space.

Is there any more pictures in front of you? That's why I sent these pictures.

Very sorry!

I use TDK for chip capacitor, Siemens for power amplifier output and Philips for inductance. I wonder if these are very poor components.

I have applied for a patent for this power amplifier in China. The switching frequency is 700kHz, 75W without fan or radiator, and the medium and high frequency can be compared with ab. Is this a hifi amplifier?

I have been engaged in research and development of class D power amplifier for more than 10 years.
You do patent in China?
You want to sell amplifier.
You want to make money.
You do not do a DIYS project, anyone can do.
You want profit.

This is not the space to sell your amplifier, maybe you do not want to understand.

There is a space in this forum you can show your "amplifier for sale". But not here.

You ignore this, people get upset. When you signed into this forum you read rules. Maybe in China no rules for you. This forum not China. Be so polite to follow forum rules.

PS Every crappy China electronics part has fake Siemens, Nichicon, BB, TI, Philips, TDK and other "most expensive name" parts. Very happy to hear you use them too.
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.