Electronics packaging specialist Schroff has developed a new retention device for securely fastening AdvancedMC modules into a MicroTCA subrack to enable such systems to withstand the extreme shock and vibration conditions laid down in the recently issued MicroTCA.1 specification.

The MicroTCA open computing architecture was originally conceived by the PICMG consortium for use in telecoms applications. To make it viable for other sectors such as defence, transportation and industrial automation, PICMG is now in the process of drawing up three ‘Rugged MicroTCA’ sub-specifications.

The first of these, MicroTCA.1 (Air Cooled Rugged MicroTCA), was adopted in the spring of 2009 and increases the shock and vibration performance requirements for MicroTCA systems from IEC 61587-1 level DL1 to level DL3.

In practice, this means that systems must now be able to withstand peak acceleration rates of 25 g in shock testing and 3g in vibration testing – figures that are several times higher than those in the original MicroTCA.0 specification.

Schroff has achieved the required performance by extending the AdvancedMC module faceplate to provide flanges at the top and bottom and by using the new retention device to fasten the module to the MicroTCA subrack.

In essence, the retention device is a screw locking mechanism that has been specially designed to be tightened without transferring any force to the connector on the MicroTCA backplane. This solution, for which Schroff has a patent pending, is detailed in the appendix to the MicroTCA.1 specification.

All that is required to convert an existing AdvancedMC module for use in a MicroTCA.1 system is a new front panel incorporating an upper and lower flange and the special retention devices.