12 Jul
2012
12 Jul
'12
3:29 a.m.
Le 12/07/2012 01:06, Joachim Steiger a écrit :
Harald Welte wrote:
[...]
I was about to suggest the same thing.
A very small 6-layer board with minimal/critical functionnality (not
even the sim) and then let people integrate that into simpler PCBs.
The RF can get out of the "critical" board via an UFL socket.
In the past, wavecom (now sierra wireless) had this idea. They developed
a modem core on a small PCB, using bga on the backside instead of plated
half holes. The packaging was made with a metallic shielding box.
Sebastien
However, now that I think of it, PCIe requires
PCB thickness to be
different (1.5mm) from what we are hading for (more like .8 or 1mm).
So I guess I'll scrap that idea.
what about making it 2 pcb?
one 'gsm module' with 'plated half holes'* and or board to board conn.
one 'carrier board' which then has the right thickness for the pcie-con.
that way the sandwhich is mechanical stable and the rf performance
shouldnt be tampered with and can even serve as additional shielding if
needed (e.g. make side opposite to the modem gnd flat).
this makes the modules as small as possible for integration into
different kinds of carriers or even a full phone.
what do you think?
[*]
http://www.multi-circuit-boards.eu/en/pcb-design-aid/design-parameters/plat…
--
roh