Re: Solder-down SODIMMs?

On 8/3/2024 6:26 AM, Jasen Betts wrote:

On 2024-07-31, Don Y <blockedofcourse@foo.invalid> wrote:

I can get some packaging advantages using COTS SODIMMs
in a design.  Cost can be a wash with soldered-down
component memory.
>
Downsides of using COTS memory *modules* is they
entice users to remove/replace/upgrade/dick-with.
And, typically come with the added cost of a socket
(which is usually rated at just a handful of insertions).
>
Anyone tried soldering-down SODIMMs (or SIMMs/DIMMs)

 Not going to work with any kind of DIMM as the contacts on both
sides serve diferent purposes.

Yes, a colleague has sent photos of his approach to that.
But, he's only looking to support *one* DIMM.  I've started
a "test" layout so we can put a few on the shaker table and
see how they fare...

It could work with simm
 

in a production design?  And, doing so in a way that
doesn't forfeit the equivalent amount of real-estate?

 You could solder them in a slot I guess, if you can handle high-rise
and deal with the routing issues.
 But why not solder ram chips instead? you have to find room for the
chips, but you save on the space taken up by the connector.

I'd have to put the RAM chips (or something else) on a daughter
card (or four) to fit the space constraints.  So, why not buy
them already mounted on said cards (instead of trying to sort
out what OTHER components can be off-boarded)?
This also lets the rest of the design remain intact as
the RAM complement changes.