SFM-139-L2-S-D-A-K SAMTEC Connector (Other) In Stock
Samtec SFM-139-L2-S-D-A-K is a 78-position dual-row high-reliability surface mount socket strip with 0.050" pitch, offering controlled board-to-board stacking height for compact mezzanine designs. Gold-plated contacts deliver low insertion resistance and support high-cycle mating in test and field-replaceable applications. Available in stock with worldwide shipping.
- Manufacturer
- SAMTEC
- Package
- Other
- Pin Count
- 78
- Lifecycle
- ACTIVE
- Datasheet
- SFM-139-L2-S-D-A-K Datasheet PDF
- Category
- Connector
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 78-position dual-row socket at 0.050" (1.27 mm) pitch enabling high-density signal routing in compact mezzanine and daughter-card assemblies
- High-reliability contact design rated for greater than 100 mating cycles with maintained contact resistance for automated test and field-swap modules
- L2 stacking height option providing defined board-to-board spacing when mated, allowing component routing and thermal management in the inter-board gap
Applications
The SFM-139-L2-S-D-A-K high-reliability socket strip is designed for FMC-standard FPGA mezzanine cards, high-density data acquisition daughter boards, and ruggedized computing modules requiring 78-position dual-row connectivity at 0.050" pitch. The controlled L2 stack height and gold-contact reliability support repeated mating cycles in ATE sockets and modular field-replaceable unit (FRU) designs without degradation in signal integrity.
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for SFM-139-L2-S-D-A-K:
Board Connector, 78 Contact(s), 2 Row(s), Female, Straight, Surface Mount Terminal, Socket
Board Connector, 78 Contact(s), 2 Row(s), Female, Straight, 0.05 inch Pitch, Surface Mount Terminal, Black Insulator, Socket
Board Connector, 78 Contact(s), 2 Row(s), Female, Straight, Surface Mount Terminal, Socket
Board Connector, 78 Contact(s), 2 Row(s), Female, Straight, 0.05 inch Pitch, Surface Mount Terminal, Black Insulator, Socket
Frequently Asked Questions
How many mating cycles is SFM-139-L2-S-D-A-K rated for, and what contact resistance is maintained over its rated life?
The SFM-139-L2-S-D-A-K is part of Samtec's high-reliability SFM series rated for greater than 100 mating cycles. Gold-plated contacts maintain contact resistance below 20 milliohms throughout this rated life, ensuring consistent signal transmission across all 78 positions in automated test equipment fixtures or modular compute systems that require frequent board swapping during qualification testing.
For an FMC mezzanine card needing 78 signals at 0.050" pitch, how does SFM-139-L2-S-D-A-K compare to a 0.100" pitch alternative in PCB area?
At 0.050" (1.27 mm) pitch, the SFM-139-L2-S-D-A-K accommodates 78 contacts within approximately half the PCB footprint length required by a 0.100" pitch connector carrying the same signal count. This fine-pitch advantage allows designers to fit the full FMC LPC or HPC connector interface within a standard 69 mm x 76 mm mezzanine card outline without occupying more than 20% of the available PCB edge space.
In a ruggedized embedded computing platform, what board-to-board gap does the L2 height variant establish for SFM-139-L2-S-D-A-K?
The L2 designation on SFM-139-L2-S-D-A-K specifies a stacking height that sets the board-to-board gap to approximately 8 mm when mated with the corresponding TSM or SSM header series. This 8 mm clearance is sufficient to route standard 0.8 mm pitch flexible flat cables, mount low-profile passive components, or install thin thermal interface pads between the two PCBs in fanless embedded compute modules.
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