[gta02-core] ECN0010: LDO2/LDO4 swap implemented
joerg at openmoko.org
Wed Nov 18 20:49:53 CET 2009
[Werner Almesberger Do 12. November 2009]:
> I've implemented the LDO2/LDO4 swap now. To keep things clear, I
> swapped the whole circuit hanging off the respective LDO, not
> just the power nets and 1714
> Note that CODEC_3V3 has its large reservoir capacitor (10 uF) on
> the AUDIO sheet.
> Anyone care to review so that we can move it to "Done" ?
> - Werner
* C4119..22, +..28 move to other side of choke (see b3004, also see suggestion below to change all to C-L-C).
*rename C3016 -> c4496 (complementary to C4406), to make mic path pseudo-sym. GND of C4496 next to gnd of jk4401
*suggestion: 1nF jk4401:6 to GND, to RF short HS MIC path when nothing plugged in
*r4303, c4306 buzzfix not implemented ... ?
thought we go make that path symmetric like formerly done
anyway, so r4303 mustn't 0R
c4307 is a nonsense, even to have pads for it. Remove C4307 footprints
we should replace (A)-R4305-(B) by (A)-R4305-(X), (X)-C4306_NC-(GND), (X)-R4399_0R-(B)
move C4303, C4304, R4305 next to wm8753, behind B3005
*make B3005 (and B4105, B3004) look like decent C-L-C filters, like e.g B4419
*kill R3004, R3005 finally!
*c3017 -> 1uF ?
*c3003 AND c3008??? Seems we don't need both
do we need B3001??
esp if we kill B3001, then c3001 AND c3005 also one of both is senseless
*suggestion: place 100pF RF suppressor C parallel to C3014, C3012 and C3013 - we
learned RF creeps in here and causes buzz. the uF-Cs are not sufficient for RF
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