Mity CPU Platforms » MityDSP-L138 (ARM9 Based Platforms)

I've attached the requested drawing, does this address your needs?

Tom

Thanks Tom, this is exactly what I needed.

Hi Tom,

I hate to be a pain, but could you dimension this from the centerline of the connector, or give me a dimension from the pad 1 center to the centerline?

Different manufacturers suggest slightly different pad footprints, but the centerline is the centerline.

I am comparing this to Figure 2 of the MityARM-1808F datasheet and something's off.

Thanks,
Emmett

Emmett,

Sorry about the late reply on this issue. Hopefully you have resolved it satisfactorily but if not I believe I have the dimension you requested:

From the Center Line of Pin 1 to the Center Line of the SODIMM connector is 161mil.

Thank you for pointing out that there was a discrepancy between the footprint and the datasheet. The issue found was that in reality the footprint should have had the outside edge of the MityDSP-L138 module moved in towards the connector 20mil due to insertion into the connector. Originally we had that outline of the module start at the center-line of the connector but in reality that was incorrect. So the outline was moved and the holes stayed in the same place. Everything now makes sense to me and hopefully the attached PDF corrects the issues you found.

If this is still wrong please let me know.

Thanks,
Alex

Now I've attached the updated PDF.

Alex

Thanks Alex
That shows everything I need.

The drawing you provided highlights a keep-out area for high profile components. What is the maximum component height allowed in this area? Is it 1.60 mm as specified in Figure 2 of the carrier board design guide?

Thanks.

Short answer is yes, 1.6mm maximum height. And you should probably hold to that height for the entire area below SOM as per the design guide, as there are a couple of small IC's outside the area in the drawing that was posted and there is an SMT NAND part (highest part on the backside of the module) which seems to extend beyond the region in the figure. I need to circle back with Alex and our CAD guys about that keep out area in the drawing, Wade, I'm not sure that's correct.

I've attached a photo of the backside of the L138F for your reference. All of the small IC's are pretty much the same height as the NAND part.

-Mike

We may have a STEP model of the module, let me see if I can get that published.

Mike, thanks for the quick response.

A STEP model is currently available at [http://support.criticallink.com/redmine/attachments/1293/MityDSP-L138F.step] unless you're referring to a newer version.

The keep-out area shown in the drawing is about half to a third of the surface area of the module (depending upon the model). I designed a carrier board to accommodate the 1.6 mm height constraint requirement for the entire area under the module but I wanted to verify that it wasn't an additional height constraint (< 1.6 mm) for that specific area of the module. Based on your answer it sounds like it isn't.

Thanks again for your help.

-Wade