r5504 - in trunk/gta02-core/docs/ecn: . ecn0032

[rehar at docs.openmoko.org]

Author: rehar
Date: 2009-08-21 08:05:23 +0200 (Fri, 21 Aug 2009)
New Revision: 5504

Added:
   trunk/gta02-core/docs/ecn/ecn0032.txt
   trunk/gta02-core/docs/ecn/ecn0032/
   trunk/gta02-core/docs/ecn/ecn0032/pi-filter.png
Modified:
   trunk/gta02-core/docs/ecn/STATUS
   trunk/gta02-core/docs/ecn/ecn0031.txt
Log:
- added new ECN0032, EMI and ESD protection for headset jack
- added commit to ECN0031

Modified: trunk/gta02-core/docs/ecn/STATUS
===================================================================
--- trunk/gta02-core/docs/ecn/STATUS	2009-08-21 03:59:52 UTC (rev 5503)
+++ trunk/gta02-core/docs/ecn/STATUS	2009-08-21 06:05:23 UTC (rev 5504)
@@ -31,8 +31,8 @@
 0029	Discuss	Move 0R resistors next to PMU after caps
 0030	Edit	Replace Calypso with Telit GE865
 0031	Discuss	Use codec to detect jack insertion and HOLD button
+0032	Discuss Add EMI and ESD protection to headset jack
 
-
 Open ECNs
 ---------
 
@@ -55,3 +55,4 @@
 0029	PMU
 0030	MODEM
 0031	AUDIO
+0032    AUDIO

Modified: trunk/gta02-core/docs/ecn/ecn0031.txt
===================================================================
--- trunk/gta02-core/docs/ecn/ecn0031.txt	2009-08-21 03:59:52 UTC (rev 5503)
+++ trunk/gta02-core/docs/ecn/ecn0031.txt	2009-08-21 06:05:23 UTC (rev 5504)
@@ -44,8 +44,6 @@
 
 
 Author: Werner Almesberger <werner at openmoko.org>
-Review: Rene Harder <rehar at saweb.de>, rev5491, We should check HOLD interrupt
-	first otherwise we might lose the jack remove interrupt if both occour
-	at the same time.
+Review: Rene Harder <rehar at saweb.de>, SVN 5491
+Commit: SVN 5503
 
-

Added: trunk/gta02-core/docs/ecn/ecn0032/pi-filter.png
===================================================================
(Binary files differ)


Property changes on: trunk/gta02-core/docs/ecn/ecn0032/pi-filter.png
___________________________________________________________________
Name: svn:mime-type
   + application/octet-stream

Added: trunk/gta02-core/docs/ecn/ecn0032.txt
===================================================================
--- trunk/gta02-core/docs/ecn/ecn0032.txt	                        (rev 0)
+++ trunk/gta02-core/docs/ecn/ecn0032.txt	2009-08-21 06:05:23 UTC (rev 5504)
@@ -0,0 +1,27 @@
+Add EMI and ESD protection to headset jack
+
+
+To prevent destroying the codec from any discharge we need to add a proper 
+ESD protection.
+We might still get RF feeding through the headset jack into the codec/system. 
+To be 100% sure it's best to add low pass EMI filter in all signal lines of the
+headset jack.
+
+based on Joerg's proposal!
+
+ESD protection 
+- add varistors (D4403/4404/4405) 5.6Vac to all headset jack signal pins
+  (same as D4402)
+
+EMI protection 
+- add Pi-filter to all signal lines of the headset jack 
+  C1=47pF C2=47pF B=KLB0603K601SA (see ecn0032/pi-filter.png)
+  possible references C4408-C4415, B4415-B4429
+- remove 22pF capacitors C4403/4404/4405
+- remove common mode choke B4102 
+
+Todo:
+cutoff frequency and attenuation at 2GHz with KLB0603K601SA needs to be verified
+(looks like impedance will be to low around 2GHz).
+
+Author: Rene Harder <rehar at saweb.de>