[Gta04-owner] GTA04 testing status

Glenn glenn.mh.dk at gmail.com
Wed Jun 29 10:30:49 CEST 2011

On 28/06/11 11.35, Dr. H. Nikolaus Schaller wrote:
> A quick update: WiFi is now working.
Hi Nikolaus

This is also great news ;-)

> 1. we did not recognize correctly that albeit the WLAB/BT combo has
>      split supply for both components, it is not allowed to power up/down
>      them separately.
>      Well, for mass production this is not a good solution and we therefore
>      consider a separate LDO for the GTA04A4 layout.

If or when you redesign the PCB, please make a (short) video where you 
edit the copper-layers via the special java program, that you said was 
better than most PCB-programs. Possibly with some youtube annotations.

"A day in a smartphone designers life"

> One observation so far: power demand is quite high. The board draws
> approx. 250-300 mA while booting. And this goes up to 450-490 mA
> after WLAN is loaded and enabled. All this for a 1200 Ah battery...

I have a similar problem with another smartphone of a major brand. If I 
do not disable wi-fi before going home from work, the battery is drained 
considerably. When I first got that smartphone, I was baffled that it 
sometimes only worked up to a day - and at other times 3 full days. My 
college told me it might be the wi-fi's fault - and it was. Please note, 
that this was with the OS built-in normal powersaving capability. All in 
all - smartphones do not like a lot of appearing and disappearing access 
points - possibly trying keeping up with weak signals.

If I open a GPS program and leave it open, the battery is drained in 
about one or two days.


All smartphones ought to have the possibility to gracefully degrade to a 
common mobile phone, when e.g. only 25% of the battery capacity is left 
- while no external power is supplied.


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