24v 50w mono class-d? Why can't I find this? - diyAudio
Go Back   Home > Forums > Amplifiers > Class D

Class D Switching Power Amplifiers and Power D/A conversion

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 17th June 2015, 05:34 AM   #1
nige838 is offline nige838  United States
diyAudio Member
 
Join Date: Dec 2009
Default 24v 50w mono class-d? Why can't I find this?

Hello,
Been using the TA2020 for a portable boombox like everybody else. I'm now looking for a amplifier with a little more power. going to use a 6s lipo, so voltage should be around 22-26v.
I came across the TDA7492MV, but it doesn't appear to be 4 ohm stable.

Link:
TDA7492MV 50W D Class Mono Digital Amplifier Board Amp Board High Power | eBay

TPA3116D2, which appears to be paralleled, but I believe that it is only beneficial if the speaker resistance is lowered (ex. 4 ohm to 2 ohm). I was told that running the TPA3116D2 in PBTL would only be a gain at 2 ohm and non-beneficial at 4 ohm. Is this correct?
  Reply With Quote
Old 17th June 2015, 05:50 AM   #2
diyAudio Member
 
abraxalito's Avatar
 
Join Date: Sep 2007
Location: Hangzhou - Marco Polo's 'most beautiful city'. 700yrs is a long time though...
Blog Entries: 122
Send a message via MSN to abraxalito Send a message via Yahoo to abraxalito Send a message via Skype™ to abraxalito
There doesn't appear to be a problem with using the TDA7492MV on music into 4ohms. Probably it can't do sustained full power into 4ohms (that will go beyond 50W), but with music it'll do fine. After all the DS does show an output filter for 4ohms (page 23, fig 27).
__________________
When irony first makes itself known in a young man's life, it can be like his first experience of getting drunk - Robertson Davies
  Reply With Quote
Old 17th June 2015, 06:48 AM   #3
irribeo is offline irribeo  Netherlands
diyAudio Member
 
Join Date: Apr 2013
Without lowering voltage it might not even be possible
  Reply With Quote
Old 17th June 2015, 09:16 AM   #4
diyAudio Member
 
Join Date: Oct 2013
tpa3116 in pbtl would still give 50w into 4ohm at 24V.
26V might be too much for the 3116, as its overvoltage protection kicks in around that voltage.
i ordered a tas5611 board yesterday.
that might be interesting to you, too.
you can also look at TDA7498E.
  Reply With Quote
Old 17th June 2015, 04:47 PM   #5
xrk971 is offline xrk971  United States
diyAudio Member
 
xrk971's Avatar
 
Join Date: Oct 2012
Location: Virginia
I am waiting for my 7498 to come in. That might just be the perfect format at 100w stereo.
  Reply With Quote
Old 17th June 2015, 04:56 PM   #6
irribeo is offline irribeo  Netherlands
diyAudio Member
 
Join Date: Apr 2013
100% certain not for 4 ohm load, the E version mentioned above might be, I quit trying STM chips, but don't know the E.
  Reply With Quote
Old 18th June 2015, 02:31 AM   #7
nige838 is offline nige838  United States
diyAudio Member
 
Join Date: Dec 2009
I think that I'm just going to go with the tpa3116 and only use one channel in the amp. My understanding is that the current drain on the other channel will be low at a watt or two. I'm working on a boombox design (read the boominator thread) and wanted some input.

Thanks,
  Reply With Quote
Old 18th June 2015, 05:35 AM   #8
irribeo is offline irribeo  Netherlands
diyAudio Member
 
Join Date: Apr 2013
Quote:
Originally Posted by nige838 View Post
I think that I'm just going to go with the tpa3116 and only use one channel in the amp. My understanding is that the current drain on the other channel will be low at a watt or two. I'm working on a boombox design (read the boominator thread) and wanted some input.

Thanks,
Bad idea imo. Do put chip in PBTL, then you don't need a dummy load.
  Reply With Quote
Old 18th June 2015, 08:19 AM   #9
diyAudio Member
 
Join Date: Oct 2013
i have a 3116 in pbtl driving a single 8 ohm driver.
no problem with that.
sounds great.
  Reply With Quote
Old 18th June 2015, 08:53 AM   #10
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
24V with a 50W into 4ohms load ???

50W into 4r0 is equivalent to 20Vpk and 5Apk into the 4r0 test load.

To get that 20Vpk (=40Vpp) you need at least 42V supply.
You CANNOT get 50W into 4ohms from 24Vdc. That is why you can't find a circuit that achieves that.

You need to cheat:
either change the supply voltage, or double up the chips into bridged format.

To get to a target of 50W into 4ohms you need two amplifiers each rated as 25W into 2ohms. This is equivalent to 10Vpk (20Vpp) and 5Apk and this is possible from a 24Vdc supply.

BTW to get 50W into your 4ohms load the peak current capability of the single channel and it's PSU will be at least double and preferably three times that 5Apk. But you have two channels, the combined PSU for the bridged amplifier will need to be able to supply 3*5Apk + 3*5Apk = 30Apk
Bridged duty is very demanding of the two amplifiers and the PSU.
__________________
regards Andrew T.
Sent from my desktop computer using a keyboard
  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
6P45S 50W mono block tube amplifier MadsKaizer Tubes / Valves 20 12th June 2015 11:30 AM
TP2050 Class-D Power Amplifier Board [50W + 50W] Agustr Class D 3 9th April 2014 06:51 PM
Help! 50w Class A or 150w Class AB debate Toobstheway Solid State 12 17th September 2007 07:05 PM
where can I find 24V wheat lamps? Luke Parts 18 12th November 2006 10:30 PM
Battery powered portable Class-D mono amp >50W RMS tonfelix Class D 1 29th April 2006 02:08 PM


New To Site? Need Help?

All times are GMT. The time now is 12:31 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2015 DragonByte Technologies Ltd.
Copyright 1999-2015 diyAudio

Content Relevant URLs by vBSEO 3.3.2