electro-music.com   Dedicated to experimental electro-acoustic
and electronic music
 
    Front Page  |  Articles  |  Radio
 |  Media  |  Forum  |  Wiki  |  Links  |  Store
Forum with support of Syndicator RSS
 FAQFAQ   CalendarCalendar   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   LinksLinks
 RegisterRegister   ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in  Chat RoomChat Room 
Live streaming at radio.electro-music.com

  host / artist show at your time
  Faux Pas Quartet and friends Music From Last Thursday
Please visit the chat
 Forum index » DIY Hardware and Software » Rob Hordijk DIY Designs
Benjolin/Zeitgeist questions
Post new topic   Reply to topic Moderators: Rob
Page 3 of 3 [53 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Goto page: Previous 1, 2, 3
Author Message
macumbista



Joined: Sep 12, 2007
Posts: 361
Location: berlin
Audio files: 3

PostPosted: Fri Aug 31, 2012 6:07 am    Post subject: Reply with quote  Mark this post and the followings unread

I'm having a bit of a situation here... I've got a beautiful-sounding Benjolin PCB made, problem is it runs really hot! I've got an 18V AC adapter running to a Vellman regulator board (LM337 and LM317 pair), Giving out 15V DC. At first I noticed that the Vellman regulators were hot because I had them choked down to 12V, so I took them up to 15V. Then I noticed that the on board regulators on the Benjolin are getting hot... I checked over the whole PCB and didn't find any shorts. Weird because it sounds fine.... Positive and negative rails each appear to be drawing 50 mA (got reading of 0.05 on the 10A setting, am I reading this correctly?). Any things to look for in particular?

[EDIT: decimal places are not my friend today. Been up all night working on this thing...]

_________________
Esoteric drones and nonlinear distortion
Custom/handmade experimental instruments
macumbista.net
Back to top
View user's profile Send private message
prgdeltablues



Joined: Sep 25, 2006
Posts: 182
Location: UK
Audio files: 11

PostPosted: Fri Aug 31, 2012 9:04 am    Post subject: Reply with quote  Mark this post and the followings unread

Well, I'm not familiar with the details, but regulating 15V down to 9V at 50mA is quite a tall order in terms of the energy = heat that the regulators have to shed. That's 6*50 = 300mW power, and if you're using the 100mA LM317 their thermal resistance to air is about 160 degC/W so expect a surface temperature of about 85 degC. That's hot, but within spec. You'd be better off adding heatsinks. Or using a lower voltage AC adapter. (As you've found out, you can reduce the demand on the on-board regulators by applying a lower voltage to them, but that simply transfers the problem to your AC/DC converter - the energy has to be lost as heat somewhere!)


Peter
Back to top
View user's profile Send private message
macumbista



Joined: Sep 12, 2007
Posts: 361
Location: berlin
Audio files: 3

PostPosted: Fri Aug 31, 2012 9:46 am    Post subject: Reply with quote  Mark this post and the followings unread

Thanks for the reply. First thing I did was put some heatsinks in last night. The instrument will be away from me for a while, it was kind of a last minute thing, but in a couple weeks I'll reevaluate the power supply. It's interesting that Rob says the Benjolin can be powered from up to 18V DC, that's why I didn't think about the heat of the regulators... Live and learn, unfortunately in that order. Just don't want to see the instrument go into thermal shutdown in the middle of a performance!
_________________
Esoteric drones and nonlinear distortion
Custom/handmade experimental instruments
macumbista.net
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic Moderators: Rob
Page 3 of 3 [53 Posts]
View unread posts
View new posts in the last week
Goto page: Previous 1, 2, 3
Mark the topic unread :: View previous topic :: View next topic
 Forum index » DIY Hardware and Software » Rob Hordijk DIY Designs
Jump to:  

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
e-m mkii

Please support our site. If you click through and buy from
our affiliate partners, we earn a small commission.


Forum with support of Syndicator RSS
Powered by phpBB © 2001, 2005 phpBB Group
Copyright © 2003 through 2009 by electro-music.com - Conditions Of Use