Attention to Details
To meet 99.999% availability goals, the xTCA specifications provide close attention to details. For example, cards can be hot-swapped. Ground pins connect before power pins during blade insertion. ESD strips on the blade connect discharges directly to the chassis. Ejector handle switches power down units upon ejection. Rogue cards that indicate a fault (e.g., high power or temperature) are powered down and isolated from other units. All blade power supplies are electrically isolated from the backplane power bus, and protected against over-voltage, undervoltage, and over-current. Hold-up capacitors guard against transient bus power dips such as those that might be caused by a power fault on another module on the redundant power bus. Power distribution is a modern pointof- load architecture.
Enclosure airflows are engineered to optimize xTCA module cooling and power dissipation. The platforms support up to 200-300 Watts per ATCA blade and up to 40-80 Watts per MicroTCA blade, permitting a single rack-mount 14-slot ATCA chassis to operate nearly 3000 Watts of electronic gear in a 55°C environment. Com mer - cial xTCA platforms generally sport redundant fans and cooling units with temperature monitoring and fan speed control. For those engineers who shun fans as a rule, low-power ATCA systems have been fielded without fans, and conduction- cooled Micro TCA systems have been demonstrated.
The xTCA specifications also raise the bar in system configuration, monitoring, and management. All commercial modules are typically heavily instrumented, with temperature, power, timing, and network health monitors. Intelligent Platform Managament Interface (IPMI) defines the management protocols and architecture, with an I2C interface to each blade for communication to the shelf managers and out-of-band channels to each platform for remote management of the systems, while still supporting common in-band management protocol standards such as SNMP. Configuration reports, electronic keying, multi-tenant support, and remote configuration updates (software, firm - ware) provide leading-edge embedded system management and control.
ATCA in the Military
More than 100 organizations currently support xTCA systems and products. Sales of xTCA systems and products are estimated to be more than $1B annually and have been projected to reach levels as high as $15B in the next five years. Although much of this rapid growth is attributed to commercial telecom, wireless, and computing systems, a number of military and aerospace programs are also using xTCA platforms for high-availability network-centric systems.