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

DD Z2B Stuck in protect
DD Z2B Stuck in protect
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 24th July 2019, 02:26 AM   #51
Perry Babin is offline Perry Babin  United States
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Look at the internal diagram of the IC and it shows a pullup resistor to an internal 5v supply.

The J111 (if that's what it is) pulls the voltage on the SD pin down to the negative rail initially but when the power supply powers up, a negative-rectifying diode charges a capacitor negatively and when the negative voltage reaches a threshold, the voltage on the SD pin is released and it rises to the voltage that it's pulled to internally.

On that same 'type 3' page, you also saw that the 21844 has a threshold of about 2.1v so I'd expect that the voltage is OK but if it's not pulling up far enough (no j111 in the circuit), I'd expect that the IC was defective (even if new).

Some ICs need a high to shutdown but most that have an overline on the SD shut down when the pin is pulled low.
__________________
Anyone who purchased the repair tutorial, email me (babin_perry@yahoo.com) if you want to download the latest version.
  Reply With Quote
Old 24th July 2019, 02:35 AM   #52
netace is offline netace  Canada
diyAudio Member
 
Join Date: Feb 2018
Location: Nova Scotia
Thanks for the clarification Perry
  Reply With Quote
Old 26th July 2019, 12:00 AM   #53
Bills amps is offline Bills amps  United States
diyAudio Member
 
Join Date: Mar 2014
ill change the IC again. and recheck. Thanks Perry.
  Reply With Quote
Old 26th July 2019, 12:01 AM   #54
Bills amps is offline Bills amps  United States
diyAudio Member
 
Join Date: Mar 2014
Thanks netace
  Reply With Quote
Old 26th July 2019, 12:43 AM   #55
Bills amps is offline Bills amps  United States
diyAudio Member
 
Join Date: Mar 2014
Changed the IC. still 3.8v on SD pin.
  Reply With Quote
Old 26th July 2019, 12:49 AM   #56
Perry Babin is offline Perry Babin  United States
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Is this with the j111 out of the circuit?

What else on the driver or main board could be keeping it down?

The 3.8v shouldn't prevent the IC from producing output but it's strange that it's not going to 5v
__________________
Anyone who purchased the repair tutorial, email me (babin_perry@yahoo.com) if you want to download the latest version.
  Reply With Quote
Old 26th July 2019, 01:19 AM   #57
Bills amps is offline Bills amps  United States
diyAudio Member
 
Join Date: Mar 2014
I pulled the j111 and still has the 3.8v on SD. Also checked pin 5 and has 12.2v.
  Reply With Quote
Old 26th July 2019, 02:21 AM   #58
Perry Babin is offline Perry Babin  United States
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Desolder and lift the SD terminal of the 2184. Does the voltage on that pin go to 5v?

Did the ICs come from a reputable distributor?
__________________
Anyone who purchased the repair tutorial, email me (babin_perry@yahoo.com) if you want to download the latest version.
  Reply With Quote
Old 4th August 2019, 04:54 PM   #59
Bills amps is offline Bills amps  United States
diyAudio Member
 
Join Date: Mar 2014
was thinking of doing that or using a separate power supply to inject 5v at the sd pin.
And the parts always come for mouser.com
  Reply With Quote
Old 4th August 2019, 05:23 PM   #60
Perry Babin is offline Perry Babin  United States
diyAudio Member
 
Join Date: Nov 2003
Location: Louisiana
Be careful if you inject voltage. This is referenced to the negative rail and your source of voltage has to be floating (with respect to all other grounds/supplies) so you can connect it to the negative rail safely.
__________________
Anyone who purchased the repair tutorial, email me (babin_perry@yahoo.com) if you want to download the latest version.
  Reply With Quote

Reply


DD Z2B Stuck in protectHide 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
Anthem MRX 300 av receiver stuck in protect. Need help. TommyVinegar Solid State 7 12th March 2019 02:45 PM
monoblock amp stuck in protect... mixalos spl Car Audio 23 31st January 2017 08:26 AM
300/2 Stuck in Protect jlind54 Car Audio 15 26th July 2014 05:37 PM
Samson Servo 550 stuck in protect...help! freestuffrocks Solid State 0 7th April 2012 07:18 AM
TL494 stuck in protect Clipped Car Audio 13 4th March 2008 04:45 AM


New To Site? Need Help?

All times are GMT. The time now is 05:07 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio
Wiki