STMM-120-02-T-D-SM SAMTEC Connector (Other) In Stock
Samtec STMM-120-02-T-D-SM is a 40-position dual-row board-stacking connector at 2.00 mm pitch with surface-mount termination, featuring phosphor bronze contacts with matte tin-over-nickel finish. This RoHS-compliant male header enables reliable vertical board-to-board interconnection in compact embedded systems.
- Manufacturer
- SAMTEC
- Package
- Other
- Pin Count
- 40
- Lifecycle
- ACTIVE
- Datasheet
- STMM-120-02-T-D-SM Datasheet PDF
- Category
- Connector
- Temp Range
- -55.0°C to 105.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- 40-position dual-row board stacking male connector at 2.00 mm pitch for high-density vertical board-to-board interconnection
- Phosphor bronze contacts with matte tin (Sn) over nickel (Ni) barrier finish ensure durability across repeated mating cycles
- Surface-mount (SM) termination with 0.257 × 0.19 inch body footprint supports compact PCB layouts in space-constrained designs
Applications
The STMM-120-02-T-D-SM is used in mezzanine board stacking architectures in embedded computing, industrial controllers, and wireless communication modules where 40 signals need to be interconnected between two PCBs at a 2.00 mm pitch. Its surface-mount termination and compact rectangular contact pattern make it suitable for processor expansion boards, memory daughter cards, and sensor interface modules requiring reliable repeated connect-disconnect cycles.
Specifications
| Factory Lead Time | 3Weeks |
| YTEOL | 8 |
| Body Breadth | 0.257inch |
| Body Depth | 0.19inch |
| Connector Type | BOARD STACKING CONNECTOR |
| Contact Finish Mating | MATTE TIN OVER NICKEL (50) |
| Contact Finish Termination | Matte Tin (Sn) - with Nickel (Ni) barrier |
| Contact Gender | MALE |
| Contact Material | PHOSPHOR BRONZE |
| Contact Pattern | RECTANGULAR |
| Contact Style | SQ PIN-SKT |
| DIN Conformance | NO |
| Filter Feature | NO |
| IEC Conformance | NO |
| Insulator Material | POLYAMIDE |
| JESD-609 Code | e3 |
| MIL Conformance | NO |
| Mating Contact Pitch | 0.079inch |
| Mating Contact Row Spacing | 0.079inch |
| Mating Information | MULTIPLE MATING PARTS AVAILABLE |
| Mixed Contacts | NO |
| Mounting Option 1 | LOCKING |
| Mounting Style | STRAIGHT |
| Mounting Type | BOARD |
| Number Of Connectors | ONE |
| Number Of PCB Rows | 2 |
| Number of Rows Loaded | 2 |
| Option | GENERAL PURPOSE |
| PCB Contact Pattern | RECTANGULAR |
| PCB Contact Row Spacing | 2.0066mm |
| Polarization Key | POLARIZED HOUSING |
| Rated Current (Signal) | 3A |
| Terminal Pitch | 2mm |
| Termination Type | SURFACE MOUNT |
| Total Number of Contacts | 40 |
| Package | Other |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8536.69.40.40 |
| Country of Origin | Malaysia, USA |
Alternate & Equivalent Parts
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What contact material and finish does the STMM-120-02-T-D-SM use, and why does it matter for mating reliability?
The STMM-120-02-T-D-SM uses phosphor bronze contacts with matte tin (Sn) plating over a nickel (Ni) barrier. Phosphor bronze provides the spring force needed to maintain consistent contact resistance across the 40 positions, while the nickel barrier prevents tin migration into the base metal over time. This combination ensures contact resistance remains stable over hundreds of mating cycles.
How does the 2.00 mm pitch of STMM-120-02-T-D-SM benefit board-stacking designs versus 2.54 mm alternatives?
At 2.00 mm center-to-center pitch, a 40-position dual-row STMM header occupies roughly 21% less board real estate per axis compared to a 2.54 mm pitch connector with equivalent position count. This size reduction is critical in miniaturized embedded systems and IoT modules where PCB area is limited, allowing designers to place the 40-pin header within a tighter layout envelope without sacrificing signal count.
What are the body dimensions of STMM-120-02-T-D-SM and how do they affect PCB footprint planning?
The connector body measures 0.257 inch (6.53 mm) in breadth and 0.19 inch (4.83 mm) in depth. These dimensions define the minimum PCB keep-out zone around the connector. When planning board layouts for stacked assemblies, designers should account for these body dimensions plus the 2.00 mm pitch land pattern to ensure adequate clearance from adjacent components on both the host board and the mezzanine module.
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