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Class D Audio Amplifier IC Forum Discussions

DennisSSebasiSt
Level 1
Level 1
First reply posted First question asked Welcome!

Hi

I connected a bench supply, a 5" 8 Ohm boombox speaker, and my laptop. With my laptop headphone out, the sound comes up, but not particularly loud, approx 78 dbA. At 5 Volts, it draws ~80mA, so using ~roughly~ 400mW. At 24 V, the sound level is and the current draw is 50mA, so about 1.2 W, yet volume is pretty much the same, about 78 dBA,

For fun, I attached a second speaker in parallel to get a 4 Ohm load. Current is 75 mA @ 24 VDC, so approx 1.8 W and sound output is 82 dBA, but I still expect this to use much more power and be much louder.

It's supposed to reach 30-80 W (per channel, load 4-8 Ohm). I thought as I increased the supply voltage, it would get louder and louder, but it's not. Is there something I'm missing? Would it help if I pre-amplified the input to this amplifier?

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Biren
Moderator
Moderator
Moderator
First like given 250 sign-ins 50 solutions authored

Hello,

MERUS 12070 output amplitude can be controlled via power mode settings, explained under the Power Mode Management topic (page 12 of the datasheet MA12070 ). It is also possible to apply a pre-amplified input but we need to make sure that input amplitudes lie within 0 - 6V.

we would need a detailed schematic to understand your system to provide further support.

Best Regards,
Biren

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Biren
Moderator
Moderator
Moderator
First like given 250 sign-ins 50 solutions authored

Hello,

MERUS 12070 output amplitude can be controlled via power mode settings, explained under the Power Mode Management topic (page 12 of the datasheet MA12070 ). It is also possible to apply a pre-amplified input but we need to make sure that input amplitudes lie within 0 - 6V.

we would need a detailed schematic to understand your system to provide further support.

Best Regards,
Biren