In the modern compact consumer electronics including smartphones, tablets, AR/VR and wearables, Flexible Printed Circuits are no longer “just interconnects”—they behave as controlled-impedance highly flexible, low loss transmission media. A high quality FPC connector is essential part of these interconnects since the impedance of connector including the parasitic capacitance and inductance coming from contact geometry, pin density and grounding all affect the data rates of complete interconnect.

I-PEX offers high-performance, high-density connectors for Flat Flexible Circuits (FFCs) and Flexible Printed Circuits (FPCs) in its EVAFLEX^® series products. By integrating EMI shielding, optimizing contact pin plating, geometry, pitch and density, these connectors offer high data rates up to 20 Gbps per lane with excellent signal integrity. High Speed FFC and FPC interconnects are commonly used in Display/Camera subsystems where signals use MIPI C-PHY, MIPI D-PHY and Embedded Display Port protocols and data rates can be up to 8 Gbps typically. 5G mmWave antenna modules can also use short FPC interconnects. 

EVAFLEX^® 5-HD series connectors offer the fastest data rate up to 24 Gbps per lane followed by EVAFLEX^® 5-VS operating up to 8 Gbps and then EVAFLEX^® 5-SE-G VT that offers up to 4 Gbps. These connectors are fully shielded against EMI leakage by integrating full 360 degrees ZenShield^®. ZenShield^® is the brand name for the I-PEX small connector series with a high-performance EMC shielding design. The 360-degree EMC shielding design prevents electromagnetic noise radiation not only from the contact points of the plug and receptacle, but also from the board mounting part (SMT positions) of the signal terminals. In addition, both plug and receptacle shields are properly connected for grounding at multiple points when the connectors are mated and are properly grounded to the board. An optimal EMI shielding results in multiple Ground contact points for noise resulting from Gigabit data rates of signals and external noise sources. By minimizing the EMI noise and optimizing impedance matching in shielded FFCs, these connectors can offer high data rates without degrading the signals. 

Figure 1 below shows the Eye Diagram for 4 Gbps signals going through EVAFLEX^® series connectors using shielded FFC as a reference. EVAFLEX^® 5-HD, EVAFLEX^® 5-VS, EVAFLEX^® 5-SE-G VT have integrated Ground Contact points which make contact with the shield of FFC as shown by Yellow highlighted area in the cross section of EVAFLEX^® 5-HD connector in Figure 2.

Additionally, channel loss budget, impedance control and Crosstalk (NEXT, FEXT) are other factors that affect the data rates in FFC/FPC interconnects. EVAFLEX^® series connectors offer higher data rates from most of industry standard FPC/FFC connectors by optimizing the impedance, minimizing the insertion and return losses, minimizing the NEXT/FEXT cross talk with unique contact pins and connector body design. These connectors can be used with both Shielded and non-shielded FPCs for design flexibility.