12 Jul
2012
12 Jul
'12
11:08 p.m.
On 12.07.2012 03:29, Sébastien Lorquet wrote:
Le 12/07/2012 01:06, Joachim Steiger a écrit :
There are more other companies that go this way (look at bt or zigbee) and you can use
this tiny
boards with every cpu of your choice because the simple interface. I don't think this
happens with
this kind of special hardware. I really don't know if it make sense to use a separate
rf-board and a
main-board. Is there any chance to use this rf-board with another platform (fpga,dsp ...)
then this
would make sense and also decrease the price of this platform.
Regards,
Mathias
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. 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?