Power supply for built-in battery powered MP3 players - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 14th October 2015, 10:39 PM   #1
kuma33 is offline kuma33  Hungary
diyAudio Member
 
kuma33's Avatar
 
Join Date: Jan 2013
Location: Szeged
Question Power supply for built-in battery powered MP3 players

I've tried to make an external power supply for an old Samsung YP-U3, then for some cheap, noname player, but i failed both cases.
I used a LM317 based circuit, but when i replaced the Samsung's internal battery with it, the player died, it didn't turn on anymore, it produced only some led-blinking (what is normal while turning on), but the screen didn't turn on, even when i placed the battery back, and removed the power supply, so eventually it died..and that happened, when i tried this with the cheap, brandless player. The circuit wasn't bad, because a couple of months ago, i found some old, AAA battery powered player, i hooked them together (i lowered the voltage first to 1,5V of course..), and it worked perfectly..
Is there some difference between the external and internal battery-powered portable players?
  Reply With Quote
Old 17th October 2015, 12:09 PM   #2
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
It should work if the power supply is correctly designed. You need to ensure that the voltage is correct both at light or no loading as well as at full load current. That can be an issue for many regulators... check the data sheet as some specify a minimum load current. If that is not met the output voltage can rise.

Something has gone astray in your build for it to cause these problems.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote
Old 26th October 2015, 05:42 AM   #3
kuma33 is offline kuma33  Hungary
diyAudio Member
 
kuma33's Avatar
 
Join Date: Jan 2013
Location: Szeged
I replaced the feedback resistor (usually "R1") from 240 to 120 Ohm, it works fine, i measured also the player's input currents, they were truly low, so maybe this was the cause of my previous player's deaths. Thanks for the suggestions, everything is fine now!
  Reply With Quote
Old 26th October 2015, 09:03 AM   #4
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
Thanks for the update. Pleased to hear you got it sorted.
__________________
-------------------------------------------------------
Installing and using LTspice. From beginner to advanced.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
DIY solar powered-battery powered-mp3-mini boombox thingy thetonywarren Class D 20 7th November 2014 06:41 AM
battery powered power amps hahfran Solid State 2 6th April 2013 05:51 PM
9VDC battery powered power supply Teti Power Supplies 14 12th May 2012 10:13 PM
Floating supply in battery powered discreet preamp aletheian Solid State 3 28th March 2007 05:42 PM
Built my battery powered headphone amp. mig-ru Headphone Systems 0 5th March 2004 12:43 AM


New To Site? Need Help?

All times are GMT. The time now is 10:04 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.
Copyright 1999-2016 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki