Strange sound inside iPhone 5S

pepelino224 · Jun 23, 2014

Hi guys, let me explain what's bothering me. Few days ago I noticed that when i put my ear to the back of the iPhone arround Apple Logo, I can hear strange sounds or rather noises like in laptops or wall charger, its something like the buzzing and tickin and its only when screen is on and phone is processing something, I read somewhere that it is a sound of a processor or coils. It has to be very quiet in the room or place where you checking that. Could you tell me guys is it normal? Or atleast do you have the same experiences with this sound? I never drop my handset and since i bought it this is the first time when i found something like this :-/ T H A N K S !!!

rich72 · Jun 23, 2014

Just tried this,and can hear it too. Bizarre!

Skull One · Jun 23, 2014

I'll be, that was quite the shocker for me. I'm at a loss to explain that sound right now but I am now very interested in finding out the why.

scifan57 · Jun 23, 2014

Could it have anything to do with the vibrator?

pepelino224 · Jun 23, 2014

scifan57 said:
Could it have anything to do with the vibrator?

I dont think so, i spoke to someone who has mobile phone repair service and he said that its normal, i was in shock as im using iPhone since the original iphone came out and i never heard that before.

pepelino224 · Jun 23, 2014

rich72 said:
Just tried this,and can hear it too. Bizarre!

Same me

pepelino224 · Jun 24, 2014

Skull One said:
I'll be, that was quite the shocker for me. I'm at a loss to explain that sound right now but I am now very interested in finding out the why.

When you find out, let me know please

APX7000 · Jun 27, 2014

Tried many apps that are CPU / GPU battery hogs. Have not heard any buzzing on battery or while charging on this 5s.

If the 5s contains a DC to DC step up converter / circuit, you will hear a buzzing noise in most cases. Many manufactures use epoxy to cover up the DC to DC converter circuitry to quiet down the buzz.

Example:
A simple DC to DC converter takes 5 volts DC (direct current) and converts it to 10 volts AC (alternating current). Once we have 10 volts AC, the AC is rectified back to 10v DC. So we've taken 5 volts DC and converted it to 10 volts DC. This whole process of DC to AC back to DC creates a buzz noise.

Could it be there is a DC to DC converter in the iPhone 5s? I see no other reason for a buzz sound.