Traditional military parts may lack sufficient signal density and typically have long lead times and are not suited to today's development tempo.
To close this gap, I found designers begin to use commercial off-the-shelf (COTS) and improved COTS components. The core challenge is to find commercially available interconnect devices that can withstand extreme environments.
Fortunately, suppliers such as Samtec have faced this technical challenge and successfully overcome it. The company's military and aerospace solutions employ commercial interconnectors known as Sudden Service, fast delivery, and rigorous environmental testing (SET). The resulting product portfolio combines commercial delivery speed with military reliability.
What is Samtec's SET?
The SET program tested the product far beyond commercial standards. First is the company's Long Life Product (ELP) certification, which simulates field and storage conditions, performing 2500 mating and 10 year mixed-gas exposure verifications on components. On this basis, the SET is tested in accordance with the applicable MIL-STD-810G and VITA 47 standards:
VITA 47.1 Mechanical and environmental: including module insertion, operating shock (OS2 level), vibration (VS3 level) and electrostatic discharge (ESD) protection capabilities
VITA 47.3 Humidity and Thermal Performance: Tested to withstand 100% relative humidity and temperature withstand over VITA 47.1 Class C4 for both operating and non-operating cycle conditions.
High Altitude: Dielectric Withstand Voltage (DWV) Measured at 70000 ft
SET can meet NASA Class D task requirements, and some products have passed the ASTM E595-77/84/90 material exhaust test specified by NASA. All SET test results are publicly available for designers to judge whether the interconnection device is suitable for its application.
Samtec SET plans to add URSA I/O super rugged cable assembly system
The SET certified interconnect devices cover a wide range of solutions, from fine-spaced, board-to-board connectors to high-performance power connectors. The URSA I/O Ultra Rugged Cable Assembly System is one of the latest products in this product family and consists of the B1SDT cable assembly and the P1M onboard connectors. These connectors use hyperbolic contacts and each pin has multiple contact points, providing high reliability and plug and unplug times. Optional configurations such as electromagnetic interference (EMI) shielding, lock panel screws, and cable stress relief further improve the rugged design.
The B1SDT cable assembly is in a dual row configuration, spaced 1.00 mm apart, each interconnector supports 80 pin positions, up to a total of 1160 I/O signal densities in a single RU panel. Typical cable length 10.00 inches (in.) B1SDT-10-28-H-10.0-1 (Figure 1) provides 20 pin positions using 28 AWG conductors.
Figure 1:10 in. URSA B1SDT-10-28-H-10.0-1 Cable Assembly has 20 locations using 28 AWG wires. Image source: Samtec)
The corresponding P1M connector can be either a through-hole or surface-mount configuration, vertical or right-angle. For example, P1M-10-01-S-D-RA-TR (Figure 2) is a 20-pin right-angle surface-mounted connector. All P1M series products have hot swap capability.
Figure 2: URSA P1M-10-01-S-D-RA-TR is a 20-pin right-angle surface-mounted connector. Image source: Samtec)
To sum up, the characteristics of URSA I/O system naturally adapt to the ground control station, radar processing unit, shipborne electronic equipment and other applications. These applications have multiple requirements such as high connector density, high maintenance frequency and severe vibration.
Mm Spacing Tiger Eye Line-to-Board System Included in SET Program
Samtec recently added a 1.27 mm Tiger Eye wire-to-board system to its SET series. Tiger Eye Series is designed for multi-contact heat treated Beryllium Copper (BeCu) contact. The elastic properties of BeCu ensure that the contacts retain their original shape after thousands of mating cycles. The mating surface is located on the flat and smooth side of each contact finger, which can minimize the coating wear, improve the stability of contact resistance performance and the service life of the overall coating.
The system includes SFSDT cable assembly and TFM connector connector, adopts polarized double-row design and supports 100 pins. Optional configuration of metal latch and screw lock, matched with Teflon coated cable, makes this kind of wire harness very suitable for avionics backplane wiring, weapon system and other applications requiring manual wiring; This ensures reliable cable performance in vibration and thermal stress environments.
For example, the SFSDT-25-28-G-08.00-DR-NDX (Figure 3) is a 50 pin, dual ended, 8 in., 4 in., and 6 in. cable assembly with 28 AWG wire size. This assembly is matched with the TFM-125-02-S-D-WT device (Figure 4). TFM-125-02-S-D-WT is a 50-pin position through-hole connector connector with solder tab to ensure reliable connection to the circuit board.