TOBY-L2 and MPCI-L2 series - System Integration Manual
UBX-13004618 - R07
Advance Information
Design-in
Page 90 of 158
Guidelines for MPCI-L2 series ANT1 / ANT2 receptacles RF connection design
The Hirose U.FL-R-SMT RF receptacles implemented on the MPCI-L2 series modules for
ANT1
/
ANT2
ports
require a suitable mated RF plug from the same connector series. Due to its wide usage in the industry, several
manufacturers offer compatible equivalents.
Table 24 lists some RF connector plugs that fit MPCI-L2 series modules RF connector receptacles, based on the
declaration of the respective manufacturers. Only the Hirose has been qualified for the MPCI-L2 series modules;
contact other producers to verify compatibility.
Manufacturer
Series
Remarks
Hirose
U.FL® Ultra Small Surface Mount Coaxial Connector
Recommended
I-PEX
MHF® Micro Coaxial Connector
Tyco
UMCC® Ultra-Miniature Coax Connector
Amphenol RF
AMC® Amphenol Micro Coaxial
Lighthorse Technologies, Inc
IPX ultra micro-miniature RF connector
Table 24: MPCI-L2 series U.FL compatible plug connector
Typically the RF plug is available as a cable assembly: several kinds are available and the user should select the
cable assembly best suited to the application. The key characteristics are:
RF plug type: select U.FL or equivalent
Nominal impedance: 50
Cable thickness: typically from 0.8 mm to 1.37 mm. Select thicker cables to minimize insertion loss
Cable length: standard length is typically 100 mm or 200 mm, custom lengths may be available on request.
Select shorter cables to minimize insertion loss
RF connector on the other side of the cable: for example another U.FL (for board-to-board connection) or
SMA (for panel mounting)
For applications requiring an internal integrated SMT antenna, it is suggested to use a U-FL-to-U.FL cable to
provide RF path from the MPCI-L2 series module to PCB strip line or micro strip connected to antenna pads as
shown in Figure 44. Take care that the PCB-to-RF-cable transition, strip line and antenna pads must be designed
so that the characteristic impedance is as close as possible to 50
: see the following subsections for specific
guidelines regarding RF transmission line design and RF termination design.
If an external antenna is required, consider that the connector is typically rated for a limited number of insertion
cycles. In addition, the RF coaxial cable may be relatively fragile compared to other types of cables. To increase
application ruggedness, connect U.FL to a more robust connector (e.g. SMA or MMCX) fixed on panel or on
flange as shown in Figure 44.
MPCI-L2 series
Baseboard
Stripline/Microstrip
Internal
Antenna
Baseboard
Application
Chassis
Connector to
External Antenna
MPCI-L2 series
Latch for
Mini PCIe
Latch for Mini PCIe
Figure 44: Example of RF connections, U.FL-to-U.FL cable for internal antenna and U.FL-to-SMA for external antenna