While the MicroTCA specification agreed in July 2006 was developed with particular focus on the telecommunications market, there has also been very strong interest in MicroTCA in other market sectors from the outset, particularly in industry. Despite its substantial advantages, however, not every user is ready or economically in a position to make the large step to adopting this new technology. Schroff has now developed a hybrid system that combines trusted technologies such as VMEbus or CompactPCI with MicroTCA in a single system. This means that the latest AdvancedMC processor modules can thus be harnessed to the wide range of existing CompactPCI or PMC I/O solutions for industrial applications with ease.

The new hybrid subrack is constructed as a standard 19" subrack in 3 U and equipped on one side with existing 19" components. On the other side of the subrack is a MicroTCA board cage into which AdvancedMC single modules can be inserted. This EMC-shielded MicroTCA board cage can be positioned left, right or centrally in the system and can have any chosen width. Everything is constructed from existing standard components.

The electronic connection can be made either with two isolated backplanes or with one that is through-connected. The simplest and most flexible method of linking the two worlds is to use two isolated backplanes - one MicroTCA backplane and one CompactPCI, PXI or VME backplane. The connection between the buses is effected in this case via an AdvancedMC module that features an MMC (module management controller) and is thus bound into the MicroTCA management concept. The board has a PCIe data interface and sends PCIe via a front panel cable. Similarly, a special card is used in the 19" section that in turn receives the PCIe via a front panel connector and places it on the parallel CompactPCI, PXI or VME bus. With minor modifications this solution can be implemented easily on standard products. Various CompactPCI, PXI, VME and MicroTCA can be easily swapped.

Another option is a through-connected backplane that contains both the MicroTCA part and the parallel PCI or VME bus. In this arrangement the backplanes of both mechanisms are brought to one plane, allowing the use of a monolithic backplane. The electrical connection between MicroTCA and the parallel bus can be created in various ways. Firstly it is still possible to link the two buses via an AdvancedMC module and a 19" board via front cables. A further possibility is a mezzanine board on the rear of the backplane that behaves towards the MCH like an AdvancedMC module and provides PCIe on PCI or VME. This logic can also be integrated directly onto the backplane.