High Clearance and Speed: A pair of
embedded ground planes within the connector interface boards (purple)
mitigates against high-speed signal losses between connector blocks on
widely separated PCBs.
Two of four copper layers within the interface board connectors of the RISE-UPô
high-speed interconnect system serve as ground planes, helping reduce signal degradation between widely spaced circuit boards. Such losses manifest themselves in lower data rates or frequency. The integrated ground planes allow transmitting data in excess of 6.25 Gbit/sec between boards 25 mm apart, as opposed to less than 2 Gbit/sec for typical high-speed pin-and-socket connectors. In the frequency domain, this performance is 3.5 GHz/differential pair versus less than 1 GHz/differential pair at a 22-mm stack height.
In addition to the ground planes, contacts mating the interface boards to the connector blocks were designed to maximize signal integrity while balancing reliability over many mate/demate cycles. The engineers' design task was ensuring long life without creating such a "beefy" structure that would act as a large antenna for crosstalk or extraneous signals. They balanced these requirements by closely mimicking the PC board traces' thickness and width in the connector contacts to avoid dimension changes that might pick up noise. Structurally, a slight barb on the connecting board traces provides retention strength. In addition, tight tolerances on the copper layer distance from the signal layer in the interface boards provide consistent, minimal impedance.
High-speed circuit boards are often widely spaced to facilitate cooling, allow component clearance, and provide easier service access. The RISE-UP interface boards accommodate standard stacking heights up to 25 mm, but taller spacing connections can be customized.
CONTACT:Ty Atkins, Samtec Tel (800) 726-8329; Fax (812) 948-5047; e-mail: email@example.com://rbi.ims.ca/3845-502