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

Group Buys Members group buys

AT2380v2 2Ch Digitally controlled Stepped Attenuator
AT2380v2 2Ch Digitally controlled Stepped Attenuator
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 12th February 2018, 10:59 PM   #51
jhenderson01075 is offline jhenderson01075  United States
diyAudio Member
 
Join Date: Nov 2004
Location: So. Cal
Default Back order

All -

The following two parts are back ordered from Mouser and I can't find a comparable substitute on their site. The latter is delayed until next Christmas! Can you recommend a substitute?


81-GRM219R71E105KA8D
GRM219R71E105KA88D
1.0UF 25V 10%
Murata Multilayer Ceramic Capacitors MLCC - SMD/SMT 6 6
MAR 30, 2018

81-GCM188R71C105K64D
GCM188R71C105KA64D
0603 1.0uF 16volts
Murata Multilayer Ceramic Capacitors MLCC - SMD/SMT 8 8
DEC 26, 2018

Thanks in advance,
Jim
__________________
Jim
  Reply With Quote
Old 13th February 2018, 06:23 AM   #52
bk856er is offline bk856er  United States
diyAudio Member
 
bk856er's Avatar
 
Join Date: Feb 2011
Location: SF Bay Area
AT2380v2 2Ch Digitally controlled Stepped Attenuator
I didn't compare your numbers against Frex's BOM, but I highlighted several OOS parts I had to sub on my Mouser order and FWIW used these @ 1uF:


GRM21BR71E105MA99L
GRJ188R71E105KE11D


BK
  Reply With Quote
Old 13th February 2018, 09:42 AM   #53
hallodeletue is offline hallodeletue  Germany
diyAudio Member
 
Join Date: Oct 2011
Location: Goettingen
AT2380v2 2Ch Digitally controlled Stepped Attenuator
Hi,
I substituted

GRM216R61E105KA12D
C0603C105K4RACTU

I have a question concerning C5, it appears twice in the BOM, one time as 10 uF/10V (together with C37, GRM21BR71A106MA73L), and the other time as 1uF/25V (together with C6, GRM219R71E105KA88D).

According to the schematic, it should be 10uF/10V, so I guess thats the save bet. If I understand it correctly, C5 is used to define the high-pass corner frequency of U1's internal offset compensation. 1uF would give a 3dB corner of 60 Hz, whereas 10uF equals 6 Hz. I guess that 10 uF is the correct value for audio applications. Is it right to assume that chosing 1uf would filter out mains hum?

Best regards,

hallodeletue
  Reply With Quote
Old 15th February 2018, 03:23 PM   #54
Frex is offline Frex  France
diyAudio Member
 
Join Date: Nov 2009
AT2380v2 2Ch Digitally controlled Stepped Attenuator
Hello hallodeletue ,

Thanks to have pointed out this error.
C5 is a 10uF (GRM21BR71A106MA73L) not a 1uF.
There is no need to filter mains hum, and it is a single pole so the attenuation will be not significant.
Note also that you will get amplitude error for low frequency input in tracking mode operation.

C8,C9 are noted in BOM 1uF/25V X7R 0603, but the ordering reference is a 16V model.
The code is ok, this caps is on 1.8V rail.

The 22uF/10V cap C29 is back ordered on Mouser but can be replaced by
from Mouser and in stock : 81-GRT21BR61E226ME3L
It is equivalent (X5R instead of x7R but no issue).

The S1 rotary encoder is also back ordered (but available again very soon) and
it is in stock at Digikey here : EN11-VSM1AF20.


Frex
  Reply With Quote
Old 8th March 2018, 03:03 AM   #55
bk856er is offline bk856er  United States
diyAudio Member
 
bk856er's Avatar
 
Join Date: Feb 2011
Location: SF Bay Area
AT2380v2 2Ch Digitally controlled Stepped Attenuator
Stencil should make board assembly easier/better!


BK
Attached Images
File Type: jpg IMG_1058.jpg (393.9 KB, 86 views)
  Reply With Quote
Old 8th April 2018, 03:54 AM   #56
bk856er is offline bk856er  United States
diyAudio Member
 
bk856er's Avatar
 
Join Date: Feb 2011
Location: SF Bay Area
AT2380v2 2Ch Digitally controlled Stepped Attenuator
Stenciled and reflowed the board today. Turned out great! Hoping I got everything oriented correctly. Now on to the rest of it...


BK
Attached Images
File Type: jpg IMG_1085.jpg (1.00 MB, 59 views)
File Type: jpg IMG_1086.jpg (1,011.4 KB, 58 views)
  Reply With Quote

Reply


AT2380v2 2Ch Digitally controlled Stepped AttenuatorHide 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
AT2380v1 // 2 Channels digitally controlled stepped attenuator Frex Equipment & Tools 112 1st September 2018 11:31 AM
WTB: Remote Controlled Stepped Attenuator Clelow Swap Meet 3 19th September 2017 03:00 PM
Digitally controlled analog attenuator Wavebourn Tubes / Valves 13 26th February 2013 09:12 PM
I ned a 6ch digitally-controlled attenuator. Anyone know of a design? Spasticteapot Digital Line Level 2 27th February 2009 08:17 PM
Digitally-controlled stepped attenuator? Spasticteapot Solid State 5 18th March 2006 11:34 PM


New To Site? Need Help?

All times are GMT. The time now is 02:24 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki