Kinetis MicrocontrollersのトピックRe: Kwikstik audio demo - high noise levels - normal?

Kwikstik audio demo - high noise levels - normal?

Scott1487 — Sat, 26 Oct 2013 18:25:55 GMT

Just got my Kwikstik and ran through the demos. I tried the 2 second audio record demo and plugged my headphones in to hear the playback. The noise level - which sounds like an oscillator running at a few kHz - is very high to the point that it's hard to hear the recorded sound over the noise.

I wondered about noise coupling in from the PC USB, which shouldn't be a problem, so I tried the demo again with an isolated USB power supply. Same noise levels.

Is this normal? I didn't expect CD quality but even the demo should record reasonable audio quality. It sounds to me like there may be a hardware issue coupling noise into the analog section of this board in which case I need to send it back.

Has anybody else noticed this?

Thanks.

Scott

Please tell me if this is posted in the wrong place. I assumed there would be a Kwikstik category but didn't find one.

Re: Kwikstik audio demo - high noise levels - normal?

perlam_i_au — Mon, 13 Jan 2014 21:12:43 GMT

As you can see, Kwikstik_Demo code for Sound_Recorder is just concept example, the sound quality with this code is not pretty good (I agree with you) but you can create or modify this code in order to improve recording & playing sample for audio signal.

Re: Kwikstik audio demo - high noise levels - normal?

Paul_Tian — Tue, 14 Jan 2014 01:49:57 GMT

Hi, Scott1487

Standing on hardware design point, TS4974 is a low-power amplifier. So you cannot use this amplifier to drive high-load.

Hope my reply can help you.

Best Regards

Paul