https://osmocom.org/https://osmocom.org/favicon.ico?16647414092020-10-07T12:14:55ZOpen Source Mobile CommunicationsM.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=198332020-10-07T12:14:55Zmschramm
<ul></ul><p>We designed this PCBA with M.2 3042 form factor modem cards in mind. The RM500Q is a 3052 M.2 card. I'd be easy to make that spin, but while Quectel, Simcom and SierraWireless 5G modem are 3052 M.2 cards, Telit offers a 5G M.2 modem (FN980m), advertised as being a 3050 card...</p>
<p>So for these 2mm difference surely a third SMT screw post wouldn't be possible. I just imagined an oblong hole / slot instead on <em>n</em> seperate posts, maybe we could hold a single of them movable it w/ a second screw+washer from bottom side.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=198342020-10-07T18:10:13Zlaforge
<ul></ul><p>Let's go for the 3052 case. If Telit wants to do their own thing... so be it. I guess<br />they will have a hard time convincing mainboard manufacturers etc. to accomodate their special<br />form factor.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=198372020-10-08T15:56:03Zmschramm
<ul></ul><p>re Telit: they seem to be serious with their 3050 ff, OK, their problem.</p>
<p>More important:</p>
<ul>
<li>it appears, that we need to support more than one length option. Then the SMT posts should not get soldered, but fixed in either of two or three positions w/ a mandatory screw(+washer?) from bott side. Likely the screw's flat pan head will do without an additional washer. </li>
<li>when touching this project, I'd like to exchange the pinheader area with the RF SMA-MHF4 area. This would also ease the space for a fourth SMA.</li>
</ul> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=200632020-10-21T15:04:10Zben.foxmoore
<ul></ul><p>We (at Accelleran) have been developing our 5G SA software, and have noticed similar issues with the Sierra Wireless EM9190 and the M.2 - USB adapters available on the market today. It seems that your design has the same problem. Is there a plan to re-spin this design allowing for the 3052 format cards?</p>
<p>I'm aware that Sysmocom and Osmocom are not the same, but I know that batches of this design are sold by Sysmocom. If there's a question of MOQ, then we may be interested in committing to an order of a small number if that helps at all.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=200682020-10-21T15:33:02Zmschramm
<ul></ul><p>ben.foxmoore wrote:</p>
<blockquote>
<p>It seems that your design has the same problem.</p>
</blockquote>
<p>It is not a problem itself, it just results from several design decisions by the modem manufacturer and by sysmocom when first selecting interesting modem cards for such a break-out. At that time, no 5G cards were available, and the desired 4G cards are/have been 3042.</p>
<blockquote>
<p>Is there a plan to re-spin this design allowing for the 3052 format cards?</p>
</blockquote>
<p>Yes, right now I prepare a spin of that design for supporting 3042 and 3052 cards. If we decide to use an oblong hole for the SMT stand-off, this will support also 3050 modem cards; however, 3042 and 3052 are mandatory.</p>
<blockquote>
<p>I'm aware that Sysmocom and Osmocom are not the same, but I know that batches of this design are sold by Sysmocom. If there's a question of MOQ, then we may be interested in committing to an order of a small number if that helps at all.</p>
</blockquote>
<p>Appreciated, I know <a class="user active" href="https://osmocom.org/users/7">laforge</a> listens.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=201312020-10-26T18:28:01Zmschramm
<ul><li><strong>File</strong> <a href="/attachments/4328">ngff-breakout_v3-obl.png</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4328/ngff-breakout_v3-obl.png">ngff-breakout_v3-obl.png</a> added</li><li><strong>File</strong> <a href="/attachments/4329">ngff-breakout_v3-3042-52.png</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4329/ngff-breakout_v3-3042-52.png">ngff-breakout_v3-3042-52.png</a> added</li><li><strong>Status</strong> changed from <i>New</i> to <i>In Progress</i></li></ul><p>Just created two deviations from the NGFF/M.2 library element, one with another hole for 3052, the other with an oblong hole / slot covering the distance from xx42 to xx52 (see attached renderings). The PCBA has to become 1 cm 'taller' giving more room for four SMA. Looking at it, I see no urge to exchange SMA section with 28pin header, but we of course can do so.</p>
<p>Plated or unplated holes or slot for spacer: for a v3, I'd tend to unplated.</p>
<p>So for a future production run of a possible v3, everything so far is prepared in terms of main effort to support (at least) one more length option.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=201332020-10-26T20:30:11Zlaforge
<ul></ul><p>On Mon, Oct 26, 2020 at 06:28:01PM +0000, mschramm [REDMINE] wrote:</p>
<blockquote>
<p>Just created two deviations from the NGFF/M.2 library element, one with another hole for 3052, the other with an oblong hole / slot covering the distance from xx42 to xx52 (see attached renderings).</p>
</blockquote>
<p>Thanks, I'd go for the 'two hole' solution, rather than the oblong hole.</p>
<blockquote>
<p>The PCBA has to become 1 cm 'taller' giving more room for four SMA. Looking at it, I see no urge to exchange SMA section with 28pin header, but we of course can do so.</p>
</blockquote>
<p>No need to create more work.</p>
<blockquote>
<p>Plated or unplated holes or slot for spacer: for a v3, I'd tend to unplated.</p>
</blockquote>
<p>How is the spacer mounted? With a screw from the bottom side?</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=201392020-10-26T23:27:35Zmschramm
<ul><li><strong>File</strong> <a href="/attachments/4331">smt-post-2screw.jpg</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4331/smt-post-2screw.jpg">smt-post-2screw.jpg</a> added</li></ul><p>laforge wrote:</p>
<blockquote>
<p>Thanks, I'd go for the 'two hole' solution, rather than the oblong hole.</p>
</blockquote>
<p>OK, dropping the other.</p>
<blockquote>
<p>No need to create more work.</p>
</blockquote>
<p>ACK.</p>
<blockquote><blockquote>
<p>Plated or unplated holes or slot for spacer: for a v3, I'd tend to unplated.</p>
</blockquote>
<p>How is the spacer mounted? With a screw from the bottom side?</p>
</blockquote>
<p>Yes, one of two variants to fix the spacer there. The mounting situation is the following one (see drawing). The spacer's body is 1.45mm high, has two steps: 0.65 top and 0,7mm bottom. Up is the mPCIe PCBA (0.8mm), the main PCBA is lowest (1.55mm) - we end up with 3.8...3.9mm, plated and tinned 4mm. This might work with 2x M2x2, but M2x3 are more common , so ordinary washers or shim rings, each wasting 1mm height, are needed then.</p>
<p>Besides this, one long screw with a nut (plus washer) would work too.</p>
<p>'Plated or unplated' here is secondary, as long as we don't solder the spacer anyway.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=201422020-10-27T08:59:40Zben.foxmoore
<ul></ul><p>mschramm wrote:</p>
<blockquote>
<p>ben.foxmoore wrote:</p>
<blockquote>
<p>It seems that your design has the same problem.</p>
</blockquote>
<p>It is not a problem itself, it just results from several design decisions by the modem manufacturer and by sysmocom when first selecting interesting modem cards for such a break-out. At that time, no 5G cards were available, and the desired 4G cards are/have been 3042.</p>
</blockquote>
<p>Understood - I didn't mean to suggest it was a bug in the design or anything like that. We were also surprised to see that the 5G modems are using a different form factor.</p>
<blockquote><blockquote>
<p>Is there a plan to re-spin this design allowing for the 3052 format cards?</p>
</blockquote>
<p>Yes, right now I prepare a spin of that design for supporting 3042 and 3052 cards. If we decide to use an oblong hole for the SMT stand-off, this will support also 3050 modem cards; however, 3042 and 3052 are mandatory.</p>
</blockquote>
<p>OK, great - either design would work fine for us.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=201602020-10-28T15:43:38Zmschramm
<ul><li><strong>File</strong> <a href="/attachments/4335">ngff-bo_v2-bottscrew.jpg</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4335/ngff-bo_v2-bottscrew.jpg">ngff-bo_v2-bottscrew.jpg</a> added</li><li><strong>File</strong> <a href="/attachments/4336">ngff-bo_v2-topscrew.jpg</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4336/ngff-bo_v2-topscrew.jpg">ngff-bo_v2-topscrew.jpg</a> added</li></ul><p>Quick check whether 2x M2 of 2 mm legth would do, and as expected they fit and hold the modem. In the picture of course the stand-off was soldered as I right now have no unsoldered one, but solder between metal stand-off and main PCB is usually not more than 0,05mm.</p>
<p>Instead of providing one M2 screw of 3mm, two M2 screws of 2mm and an unsoldered stand-off would provide mounting on either of both positions. The screws fit a PH1 screwdriver, so more than enough torque to ruin all threads involved. For increased requirements on holding force we will suggest usage of e.g. Loctite 222.</p>
<p>BTW, the PCIe_M.2 spec demands the stand-off being part of the system's GND path (as it has already been realized in v2), so we stay with a plated hole.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=201622020-10-28T19:04:20Zlaforge
<ul></ul><p>mschramm wrote:</p>
<blockquote>
<p>Instead of providing one M2 screw of 3mm, two M2 screws of 2mm and an unsoldered stand-off would provide mounting on either of both positions. The screws fit a PH1 screwdriver, so more than enough torque to ruin all threads involved. For increased requirements on holding force we will suggest usage of e.g. Loctite 222.</p>
</blockquote>
<p>I'm not familiar with any sources for M2x2 screws with flat / large diameter head. The source we buy from has M2x3 as shortest length.</p>
<p>Can you locate such a source?</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=201632020-10-28T19:55:22Zmschramm
<ul></ul><p>laforge wrote:</p>
<blockquote>
<p>Can you locate such a source?</p>
</blockquote>
<p>We have a small lab stock of them, two years old, no obvious manufacturer/distri on it. Sent you a pm with a photo of its label.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=202902020-11-09T18:06:21Zmschramm
<ul><li><strong>File</strong> <a href="/attachments/4366">ngff-bo_v3-placement.png</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4366/ngff-bo_v3-placement.png">ngff-bo_v3-placement.png</a> added</li><li><strong>File</strong> <a href="/attachments/4368">ngff-clip-anchor.jpg</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4368/ngff-clip-anchor.jpg">ngff-clip-anchor.jpg</a> added</li><li><strong>File</strong> <a href="/attachments/4369">udoo-mounting-kit-pk.png</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4369/udoo-mounting-kit-pk.png">udoo-mounting-kit-pk.png</a> added</li><li><strong>File</strong> <a href="/attachments/4370">i-o-threads-spacer.jpg</a> <a class="icon-only icon-download" title="Download" href="/attachments/download/4370/i-o-threads-spacer.jpg">i-o-threads-spacer.jpg</a> added</li></ul><p>committed a v3 candidate for 3042 and 3052 cards. For the details on the mounting holes, this is preliminary as long as we're not done with the changed mounting situation.</p>
<hr />
<p>I've again spent too much time in finally not finding any decent source for M2 screws w/ wafer head (or broad-head) in 2 mm length beside more or less random eb*y stores in CN. The very few exceptions selling 'laptop screws' believe that they trade gold, and hence their ridiculous prices.</p>
<p>During search, some more M.2 mounting options came across:</p>
<ul>
<li>some propagate a stand-off with inner and outer thread; their outer thread is 2.5mm long. They'd always scratch a plated hole, except you wide the hole and use a nut. - This was the only finding for that type of SMT mounts' drawing w/ measures on it, but some are strange there: e.g. the inner thread is likely not 3.0mm... (i-o-threads-spacer.jpg)</li>
</ul>
<ul>
<li>the clip anchor is obviously not made of conductive material, and covers parts of the RF mounting terminals on the card. (ngff-clip-anchor.jpg)</li>
</ul>
<ul>
<li>for the UDOO SBC, a very simple mounting kit gets sold (udoo-mounting-kit-pk.png) which consists of two generic metric screws w different legth, and each two spacer, nuts and washer.</li>
</ul>
<p>Neither of those are especially elegant for out use case, only the last option is something we could consider.</p>
<p>One change we should do anyway as it would allow to mount double-sided cards, is to change to the 2,45mm card offset (insted of now 1,45mm): PC-SIG spec states those two default heights, manufacturer hence offer them. In our case, the 2,45mm-TE-type with B key would be 2199230-3 for the M.2 connector (instead of 2199119-3), and respective stand-off is SM3ZS067U410-NUT1. This is only a two-liner BoM change. - This change would also ease the wafer-head screw procurement situation, as only one M2x2mm is needed per PCBA, the 2nd can be an easier-to-source M2x3; also 2x M2x2,5 is then possible. <br />If the overall number of needed wafer-head M2 in 2mm is halved with that change to one per PCBA, we again could think of source them from a random eb*y seller...</p>
<p>Some retailer use normal DIN 7985 M2 screws in 2mm on top side even w/o a washer (screw head diam is nom. 4mm on M2 DIN7985). While this likely works, they are of course not broad-head of wafer-head screws, the latter with very low-profile head. Higher heads give less mounting freedom for the MHF4 pigtails. - But such screw would be perfectly sane on bottom side, even better with washer.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=204922020-12-01T09:45:29Zlaforge
<ul></ul><p>Problem also seems to exist with SIM8200: <a class="external" href="https://twitter.com/nixdab/status/1333707836489129984">https://twitter.com/nixdab/status/1333707836489129984</a></p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=204932020-12-01T11:15:40Zmschramm
<ul></ul><p>The SIM8200-M2 is a 3052 card, so mechanically it will fit the upcoming design.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=206062020-12-14T22:09:26Zdodo34
<ul></ul><p>Is there a plan to change the micro-b to Type-C USB ?</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=206722020-12-29T19:50:19Zmschramm
<ul></ul><p>dodo34 wrote:</p>
<blockquote>
<p>Is there a plan to change the micro-b to Type-C USB ?</p>
</blockquote>
<p>The changed design for a v3 candidate is ready in the repo; we only have to decide and select sourcing of a proper (re)movable mounting post solution in favour of extending possible usage also for 3052 cards. Except this, there was no plan to touch the USB3 section.</p>
<p>The view on that might change until a production run, but unlikely.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=207062021-01-04T23:35:23Zmschramm
<ul></ul><p>mschramm wrote:</p>
<blockquote>
<p>[...] the 2,45mm-TE-type with B key would be 2199230-3 for the M.2 connector (instead of 2199119-3), and respective stand-off is SM3ZS067U410-NUT1. This is only a two-liner BoM change.</p>
</blockquote>
<p>Parts have arrived and were mechanically tested OK. So we could also incorporate this change in a v3.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=207322021-01-08T17:26:04Zlaforge
<ul></ul><p>mschramm wrote:</p>
<blockquote>
<p>mschramm wrote:</p>
<blockquote>
<p>[...] the 2,45mm-TE-type with B key would be 2199230-3 for the M.2 connector (instead of 2199119-3), and respective stand-off is SM3ZS067U410-NUT1. This is only a two-liner BoM change.</p>
</blockquote>
<p>Parts have arrived and were mechanically tested OK. So we could also incorporate this change in a v3.</p>
</blockquote>
<p>please do, and let's try to get the v3 finally out of the door and produced!</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=207482021-01-11T21:07:29Zmschramm
<ul></ul><blockquote>
<p>please do, and let's try to get the v3 finally out of the door and produced!</p>
</blockquote>
<p>OK!</p>
<p>SYS#5290 has been made for internal processing.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=210142021-02-01T06:38:05Zmarwaltemarwalte@amazon.com
<ul></ul><p>Hi folks,</p>
<p>I have some feedback regarding accommodation of current 5G data cards.</p>
<p>The 3050 form factor (used by the Telit FN980m) could be accommodated by create a small oblong hole, joined to the 3052 hole already proposed in the v3 board.</p>
<p>An example of this would be the BPlus UN32A - <a class="external" href="https://www.computextaipei.com.tw/en/product/5DBEC9D7DC3034D6417F918A20ED3D21/info.html">https://www.computextaipei.com.tw/en/product/5DBEC9D7DC3034D6417F918A20ED3D21/info.html</a></p>
<p>This would need to be plated and connected to ground, per M.2 Spec (3.0 Rev 1.2, Section 2.3.2.1) as laforge mentioned.</p>
<p>Additionally, the 2199230-3 connector should be compatible with the Telit FN980m and similar double-sided boards.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=210272021-02-01T13:22:28Zmschramm
<ul></ul><p>marwalte wrote:</p>
<blockquote>
<p>The 3050 form factor (used by the Telit FN980m) could be accommodated by create a small oblong hole, joined to the 3052 hole already proposed in the v3 board.</p>
</blockquote>
<p>Too late for a first v3 production run, PCB panel production already started.</p> M.2 (NGFF) WWAN modem USB breakout board - Bug #4782: ngff-breakount doesn't work for RM500Qhttps://osmocom.org/issues/4782?journal_id=216972021-03-23T18:57:08Zlaforge
<ul><li><strong>Status</strong> changed from <i>In Progress</i> to <i>Resolved</i></li><li><strong>% Done</strong> changed from <i>0</i> to <i>100</i></li></ul><p>the first batch of v3 of the board design has been manufactured and tested. This issue can be closed.</p>