[TangerineSDR] TangerineSDR Board Sizes and Mock-up

Rick - W2GPS w2gps at cnssys.com
Sun Sep 22 11:43:11 EDT 2019


John,

 

Here is the layer stack-up to match both the needs of the Si5345 D (6-layer)
and the thickness of the M.2 board (0.8mm) using 1oz copper. It still fits
one of the standard low cost variants from 4pcb.com. If we use a different
PCB house, it will be easy to change. As far as I can tell, the Si5345 D
documentation uses no blind or buried vias, so we will still meet the low
cost requirements.

 



 

Rick

W2GPS

 

-----Original Message-----
From: Rick - W2GPS <w2gps at cnssys.com> 
Sent: September 21, 2019 5:00 PM
To: 'TAPR TangerineSDR Modular Software Defined Radio'
<tangerinesdr at lists.tapr.org>
Cc: 'John Ackermann N8UR' <jra at febo.com>
Subject: RE: [TangerineSDR] TangerineSDR Board Sizes and Mock-up

 

John,

 

I noticed the various layout examples in the SiLabs 53xx documentation but I
did not notice the 6-layer requirement. At present, the board stack is
4-layer, 80mm (0.31") thick to match the M.2 specification.  It is set up to
match the stack-up requirements for standard configuration from low cost
board houses like 4pcb.com. I just checked and it will be easy to change
this to 6-layer, 80mm (0.31") thick board while staying within their low
cost board structure.

 

I will need to find a low cost TCXO for the base configuration. The OCXO I
show is well over $100 in 50-piece quantity. It can get to twice that if
over specified.  I hope the footprints can be overlaid to save room.

 

The board size will be a challenge, I'm sure.

 

Rick

W2GPS

 

 

-----Original Message-----

From: TangerineSDR < <mailto:tangerinesdr-bounces at lists.tapr.org>
tangerinesdr-bounces at lists.tapr.org> On Behalf Of John Ackermann N8UR via
TangerineSDR

Sent: September 21, 2019 4:43 PM

To:  <mailto:tangerinesdr at lists.tapr.org> tangerinesdr at lists.tapr.org

Cc: John Ackermann N8UR < <mailto:jra at febo.com> jra at febo.com>

Subject: Re: [TangerineSDR] TangerineSDR Board Sizes and Mock-up

 

Thanks, Rick.  I've finally started paying attention and have been thinking
about some unique GPSDO ideas.  They may change the physical parts a bit but
we're a long way from having anything finalized.

 

I think we've concluded that the RF output from the M8F module is not
acceptable for RF use -- it has a very ugly dither pattern so we will likely
need a external (TC)(OC)XO and DAC no matter what architecture we end up
with.

 

One thing to note: the SiLabs 53xx chip wants a 6 layer board and also has
some fairly funky layout requirements; a bunch of this is due to crosstalk
reduction, and the 48 MHz crystal used as the cleanup oscillator.  The chip
is physically small, but pretty complex to lay out.

 

73,

John

 

On 9/21/19 4:24 PM, Rick - W2GPS via TangerineSDR wrote:

> All,

> 

> I have been working on the clock module to see if the proposed size for
the clock module is reasonable. Attached is a 3D top view showing major
components. Not shown is the D/A to drive the OCXO and various minor
components. These may wind up on the bottom of the board.

> 

> Rick

> W2GPS

> 

> -----Original Message-----

> From: TangerineSDR < <mailto:tangerinesdr-bounces at lists.tapr.org>
tangerinesdr-bounces at lists.tapr.org> On Behalf Of 

> Scotty Cowling via TangerineSDR

> Sent: September 17, 2019 11:50 AM

> To: TAPR TangerineSDR Modular Software Defined Radio 

> < <mailto:tangerinesdr at lists.tapr.org> tangerinesdr at lists.tapr.org>

> Cc: Scotty Cowling < <mailto:scotty at tonks.com> scotty at tonks.com>

> Subject: [TangerineSDR] TangerineSDR Board Sizes and Mock-up

> 

> Here is a sneak preview of part of the TangerineSDR talk I will be giving
at DCC on Saturday.

> 

> Rick, this should be enough information on the PCB sizes to figure out if
we have enough room or not.

> 

> The CKM can be extended downward and/or to the right (when looking at the
assembly with the RPi I/O connector on top). We may have to make the DE
board larger anyway, if our CAD guy needs more routing room.

> 

> 73,

> Scotty WA2DFI

> 

> 

 

 

--

TangerineSDR mailing list

 <mailto:TangerineSDR at lists.tapr.org> TangerineSDR at lists.tapr.org

 <http://lists.tapr.org/mailman/listinfo/tangerinesdr_lists.tapr.org>
http://lists.tapr.org/mailman/listinfo/tangerinesdr_lists.tapr.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.tapr.org/pipermail/tangerinesdr_lists.tapr.org/attachments/20190922/9150753d/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 30916 bytes
Desc: not available
URL: <http://lists.tapr.org/pipermail/tangerinesdr_lists.tapr.org/attachments/20190922/9150753d/attachment-0001.jpg>


More information about the TangerineSDR mailing list