Help Identifying Diode? - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 15th February 2013, 01:55 PM   #1
Tenson is offline Tenson  United Kingdom
diyAudio Member
 
Join Date: Feb 2006
Location: Kent
Default Help Identifying Diode?

Hi Guys,

I need to fix a mic channel on my M-Audio soundcard and I think following a bit of a PSU upset some diodes that protect the input of an op-amp might have blown. The application note for the op-amp (INA163) says to use 1N4148 but the circuit in the soundcard has sot-23 types.

They say WV4 and then at a right angle to that in smaller text '73'. I've read that WV4 means a schottky barrier diode but I've no idea what sort to get to replace it. Can anybody help?
  Reply With Quote
Old 15th February 2013, 01:57 PM   #2
jaycee is offline jaycee  United Kingdom
diyAudio Member
 
Join Date: Apr 2004
Location: Norwich, UK
BAT54S
  Reply With Quote
Old 15th February 2013, 01:59 PM   #3
Tenson is offline Tenson  United Kingdom
diyAudio Member
 
Join Date: Feb 2006
Location: Kent
Hi, thanks for the fast reply. Could you let me know why it is S and not A? How do you know?
  Reply With Quote
Old 15th February 2013, 02:08 PM   #4
jaycee is offline jaycee  United Kingdom
diyAudio Member
 
Join Date: Apr 2004
Location: Norwich, UK
TBH, I googled it but have seen BAT54 used many times for this sort of input protection. I guess you need to figure out the pinout, but this should be fairly easy.

The diodes will be arranged so that they are connected to the power supply pins. One diode will be anode on the input pin, cathode to +V, the other diode will be anode to -V, cathode to input pin. Just test which pads on the pcb connect where when you unsolder the blown diode.

I would test the card by just removing the diodes and see if the input still works first. You may have further damage.
  Reply With Quote
Old 15th February 2013, 02:12 PM   #5
jaycee is offline jaycee  United Kingdom
diyAudio Member
 
Join Date: Apr 2004
Location: Norwich, UK
basically any diode would work, the BAT54 was probably chosen because it is a common dual diode available in a convenient package. Being Schottky it also has lower capacitance, which is better for audio quality as it avoids capacitive loading and forming unwanted lowpass filtering.
  Reply With Quote
Old 15th February 2013, 02:25 PM   #6
Tenson is offline Tenson  United Kingdom
diyAudio Member
 
Join Date: Feb 2006
Location: Kent
Thanks, I'll have a closer look at what pin connects to the rails.
  Reply With Quote
Old 15th February 2013, 03:14 PM   #7
Tenson is offline Tenson  United Kingdom
diyAudio Member
 
Join Date: Feb 2006
Location: Kent
You are quite right, it is BAT54S, not A.

Any idea what the small 73 text on the parts means? Ahh I just found it is a manufacture date.

Thanks again! I hope I can get it working, those INA163 are not cheap! I can't complain that M-Audio use cheap bits.
  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
Need Help Identifying Zener Diode in Sony NS999ES DVD Player rhing Digital Source 19 5th December 2010 04:36 PM
Parallel diode vs antiparallel diode phieuxuatkho Class D 6 31st October 2010 12:54 PM
diode bridge - 10000uF cap - diode tube - small cap - HV+ engels Tubes / Valves 5 29th January 2008 10:16 PM
hybrid power supply: diode bridge into diode tube engels Tubes / Valves 8 24th September 2007 09:18 AM
Help Identifying Diode evo9 Parts 11 12th September 2007 06:28 AM


New To Site? Need Help?

All times are GMT. The time now is 10:47 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2