Possible Mezz-Blade Connectors
- Samtec ET60T/ET60S (60A power, up to 24 low-speed signals)
- Samtec ERF8/ERM8 (edge-rate diff pair up to 58Gbps)
Meetings:
- https://indico.cern.ch/event/738681/ (2018-06-20)
2018-05-31
Thinking about a common blade for ATLAS L0MDT and CMS IT-DTC.
Issues with the current ATLAS design:
- FMC stacking height at 8.5mm is too high
Issues with the current CMS design (Cornell one):
- Really don't like the interposer concept with metal plates, springs etc
- Prefer stand-alone mezzanine card operation
Plus, there are two different blade designs for no obvious reason.
First, looking at low stack height connectors, but not Z-ray. (See Samtec guide) Samtec families with low stack heights:
Family | Series | Stack Height | Notes |
Sea-Ray | LPAM/LPAF | 4mm | |
Edge Rate | EDM6/EDF6 | 5mm | |
Q Series | QTH/QSH | 5mm? | 28 Gbps+, pairs, power |
QTE/QSE | 5mm | 25A GND plane | |
Ultra-Micro | EDM6/EDF6 | 5mm | |
LSS/LSEM/LSHM | 5mm | ||
ST4/SSR | 4mm |
Below is a figure with dimensions excerpted from the ATCA standard.
![]() | Seems as if we can find a 4mm or 5mm solution. This gives us about 15.7mm above a mezzanine board for components. |
Next, thinking about the logic. Is it really that hard to make a common blade? Here are some thoughts:
- Build a blade to accommodate 3 mezzanine cards
- Plan for only "low speed" mezz-to-mezz communications
(SelectIO or < 10Gbps SERDES) - Mezzanine cards would have the optics on board along with DC/DC converters and regulators
- Split the CMS IT-DTC into 3 parts
- Eliminate the "blade FPGA" from the ATLAS design and designate one mezz card as "master"
(this could be a different design).
ATLAS requirements
- Sector logic
Last modified 6 years ago
Last modified on May 21, 2019, 3:50:38 PM