Humming/Buzzing LED-Display?

Hello,

I have a 8 GB Clip and I recognized recently that the display makes a tiny (really tiny!) noise, like its humming. When the display lighting shuts off, it stops, too.

Could that be a simple sign of wear or do I have to expect that it’ll explode someday? ;)  

Never noticed until you mentioned it - but yes, mine also does that. You really have to hold the Clip next to your ear to hear it though. There seems to be a buzz from the display plus some whine from one of the voltage converters. I wonder which parts exactly emit these noises, I don’t think there are too many inductors in there…

@corey wrote:

Hello,

I have a 8 GB Clip and I recognized recently that the display makes a tiny (really tiny!) noise, like its humming. When the display lighting shuts off, it stops, too.

Could that be a simple sign of wear or do I have to expect that it’ll explode someday? ;)  

That noise is from a switch mode power supply.  The display needs a voltage higher than the battery supplies so a boost converter is used to supply the voltage.  It’s a common circuit technique to get high voltage rails for these portable devices off a 4V or lower battery.  I design those kinds of chips.  What is surprising is Sandisk used a switching frequency low enough to be audible. That’s not common these days but may have been done to keep power consumption and/or cost low. If you push enough power through a thin wire and at low enough frequencies you can hear it (been there, done that).

I would guess the noise either comes from tiny inductor in the Clip or even the display itself.

Message Edited by tnmats on 10-26-2009 02:37 PM

Thank you for your answers!
I discovered it by accident and it doesn’t bother me, since I usually don’t press my ear against my clip ^^

Just wanted to assure that it’s not something I should worry about.

(But it’s weird that in comparison my 4 GB clip is absolutely mute…)

But the real question is, does it hum on pitch?

:wink:

In all probability you may need to do some burrowing. Pull it off , it will have a section number stepped on it. Google it or even ebay or Amazon. If not dont limit your self you can without much of a stretch adjust anything comparable 12 volt

The noise may be due to low voltage. When a low voltage is been used to power LED displays that’s when things like this happen. I will suggest you power it with a higher voltage or use a booster to boost the power voltage