NAT-MCH-RTM (including options -BM, -FPGA, -COMex)
Rear Transition Module (RTM) for MCH in MTCA.4.x system, providing application processing resources and control functions for MTCA auxiliary µRTM backplanes, e.g. for LLRF
Single slot solution providing a NAT-MCH-PHYS80 with a fully user-accessible Intel® x86 CPU  including storage and allowing full control of an optional µRTM backplane, e.g. a LLRF backplane, located behind a standard MTCA.4 backplane. The user can choose from a set of Intel® x86 CPU, strating from a dual core Celeron® over a quad core i3 or i9 up to a six core Xeon® E3 based on the latest generation of Intel® CPUs. The NAT-MCH-PHYS80 and its associated rear transition module NAT-MCH-RTM/-BM-FPGA-COMex, both members of the NAT-MCH family of products, bring additional flexibility and scalability to MTCA.4 and MTCA.4.1 systems. This unique combination releases slots normally occupied by processor Advanced Mezzanine Cards (PrAMCs), storage and graphic AMCs by using the space behind the MCH slot(s) in a MicroTCA.4.1 chassis. The optionally mounted Type-6 COMex module connects by a x16 link to the 80 port PCIe switch at the MCH, while a standard Processor AMC usually provide a x4 or a x8 PCIe link only. In addition the COMex modules directly connects to the 1GbE base fabric switch at the MCH and also has access to the two SATA SSDs sites located on the NAT-MCH-PHYS80. The COMex module can operate as a PCIe root complex. What's more, the NAT-MCH-RTM/-BM/FPGA allows the NAT-MCH-PHYS80 to fully control the µRTM-backplane e.g. NAT-LLRF-Backplane, which is located behind the standard MTCA.4 backplane for AMCs, and any item connected to this additional backplane, such as eRTM (extended RTM), RPM (Rear Power Modules) and (optionally) standard RTMs. The NAT-LLRF backplane allows you to combine systems that are traditionaly separate - one for the digital part and one for the analogue part - into one singe MicroTCA system. The required mechanics and the management extensions have been introduced to the PICMG MTCA.4.1 working group already in order to make these optional extensions available as part of the open MicroTCA.4.1 standard. Using rear power modules, any RTM that connects to the µRTM-backplane (NAT-LLRF-Backplane) can be powered independently from its associated AMC, thus providing a higher power budget per AMC/RTM slot combination. Variants NAT-MCH-RTM
NAT-MCH-RTM-BM
NAT-MCH-RTM-BM-FPGA
All three variants from above can be fitted with a Type-6 COM Express module, e.g. equipped with a latest generation Intel® x86 CPU. Any of the three part numbers above then gets ammended by a -COMex-XY with XY specifying the COM express module (please see below). The NAT-MCH-RTM connects to the the NAT-MCH-PHYS80 via the zone 3 connector and offers the COM Express module
When available from the COM Express module, other I/O is brought to the front panel of the RTM, i.e. (by default)
Using COMex modules N.A.T can provide the latest CPU generation with all kinds of memory variants (size, ECC, etc.) in industrial and extended temperature grade. All available CPUs are from Intel®’s embedded roadmap with low power at 25 W TDP to avoid thermal or electrical overload in your MTCA.4.x systems. By default N.A.T. hold the following Type-6 COMex modules equipped with Intel® processors available (others are available on request):
Family of MCH products The NAT-MCH-RTM is associated to the NAT-MCH family of MCHs which consists of:
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MicroTCA is a high-channel-density system standard. In order to increase system reliability and ease of maintenance, improve cable management, reduce performance limitations and the space occupied by external RF cabling, and finally for better EMC shielding of sensitive analog signals, N.A.T. GmbH has collaborated with DESY to develop a unique concept for extending the MicroTCA.4 system capabilities. The MicroTCA low level RF-Backplane (NAT-LLRF-Backplane) for µRTM cards is a hardware implementation of this new extension embedded in a MicroTCA.4 crate. The unit is a passive RTM backplane suited for the interconnection of high-precision RF and CLK signals and the delivery of high-performance managed analog power supply for µRTM and extended RTM (eRTM) modules. High-frequency signal distribution network was designed to operate in the DC – 6GHz band. |
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The NAT-MCH-RTM-BM-FPGA is the standard rear transition module for the NAT-MCH-PHYS80 and functions as carrier for any Type-6 COM Express module.
- Connections to µRTM backplanes e.g. NAT-LLRFÂ
- I2C interface to EEPROM
- IPMI to two Rear Power Modules
- IPMI to three eRTMs, which habe no connection to front AMCs
- FPGA for a application specific intercommunication bus
- Mounting slot for any Type-6 COM Express module, I/O of COM Express slot connected to PHYS80 via Zone 3 connector or available at front panel
Available with optional NAT-MCH-RTM-COMex-XY
- I/O on front panel of RTM:
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- 2x DisplayPort (high resolution graphics)
- 4x USB3.0
- 1x GbE at rear panel
- Connections to the NAT-MCH-PHYS80
- 2x SATA connection to two SSD slots
- One x16 PCIe Gen3 link to fat pipe switch (Fabrics D-S)
- One 1GbE connection to GbE switch (Fabric A)
NAT-MCH-RTM is available in variants as follows: NAT-MCH-RTM
NAT-MCH-RTM-BM
NAT-MCH-RTM-BM-FPGA
All three variants above can be fitted with a Type-6 COM Express module. The part numbers above then are ammended by a -COMex-XY at the end, XY specifiying the COM Express module. |
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Standard
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 | Storage One 2.5 inch SSD with 128 GB mounted on NAT-MCH-PHYS80 or two 1.25 inch SSD in RAID mode on request mounted on NAT-MCH-PHYS080
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Title
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Description
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Format
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Size
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Rev #
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Date Last Modified
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nat-mch_ds | Data sheet and NAT-MCH family overview | 1.179 KB | 1.4 | 06-07-2012 | |
NAT-LLRF | NAT-LLRF MicroTCA Low Level RF-Backplane web page | Â HTML | Â | Â | Â |
nat_mch_rtm_comex_v2x_man_hw |   Hardware Manual for RTMs v2.x | pdf | 1.4 MB | 1.1 | 18-12-2017 |
nat_mch_rtm_HWv24_hw | Hardware Manual for RTMs V2.4 |
1 MB | 1.1 | 29-07-2021 |
For further documentation on the NAT-MCH (i.e. technical reference manuals) please contact us using the contact form. Thank you.

Product Code: NAT-MCH - [Options]
Option |
Description |
-RTM |
Double-wide full-size rear transition module and COM Express carrier |
-RTM-BM |
as above plus Backplane Management and Zone2 connector for µRTM backplanes eg LLRF backplane |
-RTM-BM-FPGA |
as -RTM-BM plus ZYNQ-FPGA to implement separate bus eg SPI on LLRF backplane to access eRTMs |
-COMex-Ce-16 |
Type-6 COM Express module with Celeron® G-4932E dual core CPU with CM246 chipset and 2x 8GB DDR4 ECC |
-COMex-i3-16 |
Type-6 COM Express module with i3 9100HL quad core CPU with CM246 chipset and 2x 16GB DDR4 ECC |
-COMex-XE-32 |
Type-6 COM Express module with Xeon® E3 E-2276ML six core CPU with CM246 chipset and 2x 16GB DDR4 ECC |
Software:
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Title
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Description
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Version
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Released
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NATView | Java based GUI (Graphical User Interface) for monitoring and control of MTCA systems. | 3.00 | 15-03-2018 |
NBSP-LINUX-NAT-MCH-RTM | Ubuntu Linux for NAT-MCH-RTM-COMex-XY | on request | on request |