Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Multi-output 9v supply using MC34063?
Multi-output 9v supply using MC34063?
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 13th March 2019, 09:45 PM   #21
matt_garman is offline matt_garman  United States
diyAudio Member
 
Join Date: Feb 2008
Location: Chicago, Illinois, USA
Multi-output 9v supply using MC34063?
Alright, how about something like this:

Battery -> regulator -> multiple isolated DC-DC converters (one per output)

I'm looking at something like the MuRata NMG1209SC for the isolated DC-DC converters. 12v input, 9v output, decent ripple and noise if an inductor and capacitor is added to the output.

For the first converter, to get from battery voltage to 12v to power the isolated DC-DC converters, how about something like this: TPS61085T?

I think that checks all the boxes (except cost, those isolated DC-DC converters aren't cheap). Seems pretty simple, unless I'm overlooking something (certainly wouldn't be the first time!).
  Reply With Quote
Old 13th March 2019, 10:02 PM   #22
FauxFrench is offline FauxFrench  France
diyAudio Member
 
Join Date: Dec 2017
Location: The mountains, calm and quiet.
The principle should work but the TPS61085T seems not to be sufficiently powerful. The switch can max. handle 2A and with 3V input that makes 6W (no margins). Then, you have the losses in the first common regulator and the losses in the isolated DC-DC converters. Not much power will be left for the loads.
  Reply With Quote
Old 14th March 2019, 02:59 AM   #23
PRR is offline PRR  United States
diyAudio Member
 
PRR's Avatar
 
Join Date: Jun 2003
Location: Maine USA
Quote:
Originally Posted by turk 182 View Post
why the need for isolation when in the end it's going to power a bunch of guitar pedals that are going to share a common ground via a series link chain of guitar cables?
1) It seems better to not have parallel signal and power ground commons.

2) Some pedals take *reverse* polarity power.
  Reply With Quote
Old 14th March 2019, 06:37 PM   #24
matt_garman is offline matt_garman  United States
diyAudio Member
 
Join Date: Feb 2008
Location: Chicago, Illinois, USA
Multi-output 9v supply using MC34063?
Quote:
Originally Posted by FauxFrench View Post
The principle should work but the TPS61085T seems not to be sufficiently powerful. The switch can max. handle 2A and with 3V input that makes 6W (no margins). Then, you have the losses in the first common regulator and the losses in the isolated DC-DC converters. Not much power will be left for the loads.
I think you're right. My read of the graphs on page 5 of the datasheet suggests it might be a little worse than that: max load current is about 0.6A with 3V supply and 9V output. That's 5.4W output. Probably OK for a couple DC-DC converters, but doesn't leave much headroom.

FWIW, I likely won't let the of the 18650 cells drop below 3.6v. (Technically they go down the 3v, but typical recommendations suggest staying above 3.6v, to extend the cell's life.)

How about this: PAM2422?

Another option maybe: TPS55340. But that looks to have a more complicated implementation.
  Reply With Quote
Old 14th March 2019, 07:38 PM   #25
turk 182 is offline turk 182  Canada
diyAudio Member
 
Join Date: Oct 2012
Quote:
Originally Posted by PRR View Post
1)2) Some pedals take *reverse* polarity power.
i think i understand what your hinting at here but would you mind elaborating on this?

i've never known this to be a problem...or are those short polarity flip cables a lark?

Last edited by turk 182; 14th March 2019 at 07:42 PM.
  Reply With Quote
Old 14th March 2019, 07:50 PM   #26
FauxFrench is offline FauxFrench  France
diyAudio Member
 
Join Date: Dec 2017
Location: The mountains, calm and quiet.
The PAM242X seems most promising. The TPS55340 is a versatile input voltage chip (2.9V-32V!) but the graph on the first page of the datasheet hints a quickly dropping efficiency with low input voltages. The PAM242X is designed for low input voltages, just as you want to use it for.
The PAM2423 can probably be used with your 18650 cells up to an output current of around 1A at 9V. Graphs on page 5 of 10 of the datasheet. PAM2422 should do as well.
  Reply With Quote

Reply


Multi-output 9v supply using MC34063?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Real multi room, multi input-multi output audio system for smart home gryzli133 PC Based 3 26th January 2018 04:15 PM
Using 2 MC34063 for CMOY virtual ground KungFuPanda Chip Amps 4 21st February 2012 07:44 PM
MC34063 blues astouffer Power Supplies 3 12th June 2009 01:23 PM
Multi power supply argonrepublic Power Supplies 0 7th March 2006 01:04 AM
My multi-format output dac AD1865 Digital Source 2 8th December 2003 11:21 PM


New To Site? Need Help?

All times are GMT. The time now is 01:14 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki