Power Amp Class-D

Today I got a power amp from NPE.
It's Class-D Power Amp 20W, 665 BHT

20 WATTS CLASS D Specifications 1. 20W at 8 ohms 16 Vcc 2. No Heatsink 3. Short Circuit Protection 4. Vcc 9-18 V 5. Imax 1.3 A at Po 20 W 6. Shutdown 1 uA

Can't believe that it requires no heat sink.
I used to do 2W power amp, it's very hot and have to use heat sink.
And also can't believe that it requires only 1.5A transformer.
Most 30W power amp requires 5-6A transformer.

But when I tested it to drive a subwoofer speaker, powered by very cheap 1A transformer.
It's soooo amazing!!!
After continuous using about 4 hours, no heat generated at all. Like it's not operating.
This very cheap 1A transformer is not enought to supply the AA battery charger.
But this power amp powered by that transformer can shake my door!

Class	Efficiency
A	25% (theoretical)
AB	less than 78.5% (theoretical)
D	80-95% (practical)

(Credit http://en.wikipedia.org/wiki/Electronic_amplifier)

[Sat 11 Oct 2008]
Finally, I put my power amp class-D in an (antiquated) box.
Althought it's looked uninterested, but it can shake the room, no heat generated.





If you want a subwoofer filter, try this. Subwoofer Filter

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