r5532 - in trunk/gta02-core: . docs/ecn

[rehar at docs.openmoko.org]

Author: rehar
Date: 2009-08-23 23:37:35 +0200 (Sun, 23 Aug 2009)
New Revision: 5532

Added:
   trunk/gta02-core/docs/ecn/ecn0033.txt
Modified:
   trunk/gta02-core/audio.sch
   trunk/gta02-core/docs/ecn/STATUS
   trunk/gta02-core/docs/ecn/ecn0022.txt
Log:
- changed ECN0022 according to use tantalum caps
- replaced symbol of C4111/4110/4308/4307 with polarized caps
- added ECN0033 "Replace coupling capacitors for input/output lines"

Modified: trunk/gta02-core/audio.sch
===================================================================
--- trunk/gta02-core/audio.sch	2009-08-22 22:55:39 UTC (rev 5531)
+++ trunk/gta02-core/audio.sch	2009-08-23 21:37:35 UTC (rev 5532)
@@ -1,4 +1,4 @@
-EESchema Schematic File Version 2  date Sat 22 Aug 2009 04:19:18 PM CDT
+EESchema Schematic File Version 2  date Sun 23 Aug 2009 03:27:46 PM CDT
 LIBS:power,device,conn,gta02-core
 EELAYER 24  0
 EELAYER END
@@ -952,7 +952,7 @@
 	1    0    0    -1  
 $EndComp
 $Comp
-L C C4306
+L CP1 C4306
 U 1 1 4A41A9BF
 P 3450 9400
 F 0 "C4306" H 3500 9500 50  0000 L CNN
@@ -971,14 +971,14 @@
 	1    0    0    -1  
 $EndComp
 $Comp
-L C C4307
+L CP1 C4307
 U 1 1 4A41A957
 P 3450 7600
-F 0 "C4307" H 3500 7700 50  0000 L CNN
-F 1 "NC" H 3500 7500 50  0000 L CNN
+F 0 "C4307" H 3550 7500 50  0000 L CNN
+F 1 "NC" H 3550 7700 50  0000 L CNN
 F 2 "1206" H 3550 7750 60  0001 C CNN
 	1    3450 7600
-	1    0    0    -1  
+	1    0    0    1   
 $EndComp
 $Comp
 L GND #PWR0208
@@ -1250,24 +1250,24 @@
 	1    0    0    -1  
 $EndComp
 $Comp
-L C C4110
+L CP1 C4110
 U 1 1 4A3EFB33
 P 11750 9350
 F 0 "C4110" V 11650 9150 50  0000 L CNN
-F 1 "100u" V 11800 9500 50  0000 L CNN
+F 1 "100u" V 11800 9550 50  0000 L CNN
 F 2 "1206" V 11600 9100 60  0001 C CNN
 	1    11750 9350
-	0    1    1    0   
+	0    -1   1    0   
 $EndComp
 $Comp
-L C C4111
+L CP1 C4111
 U 1 1 4A3EFB18
 P 11750 8950
 F 0 "C4111" V 11650 8750 50  0000 L CNN
-F 1 "100u" V 11800 9100 50  0000 L CNN
+F 1 "100u" V 11800 9150 50  0000 L CNN
 F 2 "1206" V 11600 8700 60  0001 C CNN
 	1    11750 8950
-	0    1    1    0   
+	0    -1   1    0   
 $EndComp
 NoConn ~ 8850 3450
 $Comp

Modified: trunk/gta02-core/docs/ecn/STATUS
===================================================================
--- trunk/gta02-core/docs/ecn/STATUS	2009-08-22 22:55:39 UTC (rev 5531)
+++ trunk/gta02-core/docs/ecn/STATUS	2009-08-23 21:37:35 UTC (rev 5532)
@@ -32,6 +32,7 @@
 0030	Edit	Replace Calypso with Telit GE865
 0031	Execute	Use codec to detect jack insertion and HOLD button
 0032	Discuss Add EMI and ESD protection to headset jack
+0033    Discuss Replace coupling capacitors for input/output lines
 
 Open ECNs
 ---------
@@ -56,3 +57,4 @@
 0030	MODEM
 0031	AUDIO
 0032    AUDIO
+0033    AUDIO

Modified: trunk/gta02-core/docs/ecn/ecn0022.txt
===================================================================
--- trunk/gta02-core/docs/ecn/ecn0022.txt	2009-08-22 22:55:39 UTC (rev 5531)
+++ trunk/gta02-core/docs/ecn/ecn0022.txt	2009-08-23 21:37:35 UTC (rev 5532)
@@ -14,8 +14,9 @@
 headset jack.
 
 To improve the audio quality we need to replace C4111 and C4110 with a 100uF
-capacitor so the lower cutoff frequency with a 32 Ohm headphone will be at 50Hz
-(assumes R4407 & R4405 = 0R, see ECN0015 "Remove Calypso serial interface on
+polarized tantalum capacitor so the lower cutoff frequency with a 32 Ohm 
+headphone will be at 50Hz.
+(assumed R4407 & R4405 = 0R, see ECN0015 "Remove Calypso serial interface on
 headset")
 
 

Added: trunk/gta02-core/docs/ecn/ecn0033.txt
===================================================================
--- trunk/gta02-core/docs/ecn/ecn0033.txt	                        (rev 0)
+++ trunk/gta02-core/docs/ecn/ecn0033.txt	2009-08-23 21:37:35 UTC (rev 5532)
@@ -0,0 +1,19 @@
+Replace coupling capacitors for input/output lines
+
+
+Wolfson recommends 1uF coupling capacitors for input and output lines of the 
+codec [1]. However in the current GTA02 100nF capacitors are used for coupling.
+To follow Wolfson's recommendation we will change all line input/output 
+coupling capacitors to 1uF.
+
+Replace the following capacitors with 1uF (CM105X5R105M16AT):
+- C4304 and C4303 (MIC input)
+- C3007 and C3008 (GSM modem input)
+- C3018 and C3011 (GSM modem output)
+- C3016 (headset MIC)
+
+
+[1] http://www.wolfsonmicro.com/uploads/documents/en/WM8753.pdf (p. 88)
+
+
+Author: Rene Harder <rehar at saweb.de>