Products
Board-to-Board Connector Solutions
Soulin board-to-board connectors, also known as PCB to PCB connectors or BTB connectors, deliver compact, high-density interconnections with excellent solderability, low contact resistance, and long mating life. The product range includes pin headers, female headers, box headers, round/machined pin connectors, and DIN 41612 / FutureBus backplane connectors, available in straight, right-angle, and press-fit configurations with SMT and THT mounting. These board-to-board connectors ensure reliable performance under temperature, vibration, and repeated mating. As a trusted supplier of B2B interconnect solutions, Soulin supports industrial automation, telecom, computing, and consumer applications. Explore our portfolio to compare different types of circuit board connectors for your design needs.
Soulin's Board-to-Board Connector Types
Pin Headers
Soulin pin headers are engineered for stable solderability and low contact resistance, using PA9T/LCP housings, brass contacts, and gold or tin over nickel plating. They deliver consistent reliability across industrial, telecom, computing, and consumer electronics.
Available in pitches from 0.8 to 5.08 mm, with 1–80 pins in 1–3 rows, our range covers straight and right-angle orientations, SMT, through-hole, and press-fit types. Current ratings span 1.0 to 7.0 A with 500–1000 V withstand voltage, making them versatile for high-density and high-power designs alike.
Female Headers
Soulin female headers ensure secure mating with pin headers, offering low insertion force and stable contact performance. They are widely used in industrial, telecom, computing, and consumer applications.
The range supports pitches from 0.8 to 5.08 mm (incl. 1.27×2.54 mm), with 1–2 rows and up to 80 pins. Configurations include straight (180°) and right-angle (90°), with SMT, THT, and press-fit mounting. Features such as sealed versions, caps, and posts, plus Y-type or U-type contacts, provide flexible interconnect options.
Round Pin Headers / Machined pin headers
Soulin round pin headers (machined pin headers) offer high-reliability connections with precision-turned contacts, ensuring stable mating, low contact resistance, and long mechanical life. They are widely applied in industrial control, automotive, telecom, instrumentation, and consumer electronics.
The series covers pitches from 1.0 to 2.54 mm, with 1–2 rows and up to 64–80 pins. Configurations include straight (180°) and right-angle (90°), with SMT and THT mounting options. Machined pins provide excellent retention and durability, supporting current ratings of 1.0–5.0 A, insulation resistance of ≥1000 MΩ, and contact resistance of ≤20–30 mΩ. Available with closed-entry sockets, solder-tail or press-fit types, they are suitable for high-reliability board-to-board and socket applications.
Box Headers
Soulin box headers feature shrouded housings that prevent mismating and protect pins from damage, ensuring secure PCB interconnections. With high-temperature thermoplastic insulators and brass pins plated in Au or Sn over Ni, they provide stable performance for computers, telecom, industrial, and consumer electronics.
The range includes 1.0 / 1.27 / 2.0 / 2.54 mm pitches, up to 40 pins, with orientations in straight (180°) and right-angle (90°). Options support SMT or THT mounting, standard heights such as H5.7 mm, and male pin style for IDC cable or board-to-board systems. Typical ratings are 1.0–3.0 A current capacity, 250–500 V AC withstand voltage, and ≤30 mΩ contact resistance, all UL and RoHS compliant.
Backplane Connectors
Soulin backplane connectors provide reliable, high-density interconnects for modular electronic systems, ensuring signal integrity and mechanical robustness in industrial control, telecom, computing, and instrumentation.
The range includes DIN 41612 connectors with 2.54 mm pitch, 1–3 rows (up to 160 pins), in straight and right-angle types, supporting THT and press-fit assembly. FutureBus connectors extend capacity to 320 contacts on 2.0 mm pitch, optimized for high-speed parallel bus performance. Typical ratings span 2.0–3.0 A per contact, 250–500 V AC withstand voltage, and ≥400–500 mating cycles, with copper alloy contacts and Au/Sn over Ni plating for long-term durability.
How Do We Stack PCBs?
Board-to-board (BTB, also written as B2B) connectors link PCB-to-PCB in three common orientations to meet space, z-height, SI/EMC, and assembly constraints.
- Vertical / Mezzanine — Small footprint; adjustable stack heights (≈5–25 mm); ideal for compact modules.
- Horizontal / Coplanar — Low-profile edge-to-edge connection; straightforward shielding along the plane.
- Perpendicular / Mother–Daughter — Scalable backplanes and modular systems common in storage/telecom.
| Orientation | Typical Stack Height | Best For | Design Notes |
|---|---|---|---|
| Vertical / Mezzanine | 5–25 mm | High I/O density, compact devices | Reserve keep-out under connector; plan probe/repair access |
| Horizontal / Coplanar | Low-profile | Thin enclosures, shield cans | Align board edges; consider edge stiffeners for drop/vibration |
| Perpendicular / Mother–Daughter | N/A | Backplanes, scalable daughter cards | Check insertion/withdrawal forces; use guides for alignment |
Quick Checklist
- Freeze orientation early (SI/EMC/thermal/mechanical).
- Lock stack height from enclosure → connector → tolerance stack-up.
- Add ground stitching / via fences around BTB to control return paths.
- Verify mating cycles and total insertion force.
- Plan tooling & test access on both PCBs.
What Are Connector Pitches?
Pitch is the center-to-center spacing of adjacent contacts. Multi-row BTB may use different in-row and row-to-row pitches.
How Pitch Affects Design
- Space & Density — Smaller pitch increases I/O per area.
- Electrical — Larger pitch typically supports higher current and creepage/clearance.
- Assembly — Fine pitch favors SMT with tape-&-reel & P&P caps; TH for ruggedness.
| Pitch (mm) | Typical Use | Typical Current/Pin* | Notes |
|---|---|---|---|
| 0.4–0.5 | Wearables, handheld | ≈0.5–1.0 A | Highest density; strict coplanarity/stencil control |
| 0.8–1.00 | Industrial / IoT | ≈1–3 A | Balanced density vs current |
| 1.27 | General purpose | ≈2–4 A | Broad ecosystem; robust process window |
| 2.00–2.54 | Power-rich modules | ≈3–8 A | Higher creepage; easier thermal margin |
*Guidance only. Validate with data sheets, derating curves, PCB copper, and ambient conditions.
Fast Sizing Rule
Total current ≈ power pins × current per pin × 0.7 (derating)
Example: 4 pins × 5 A × 0.7 ≈ 14 A.
How Many Rows Do I Need?
- Single row — Simple routing; narrow footprint.
- Dual row — Higher I/O per footprint; common in mezzanine stacks.
- Triple / Quad rows — Extreme density; plan escape routing and reference returns.
Grounding Patterns for Signals
GSSG (diff pair with flanking grounds) SGSG (interleaved for crosstalk control) GGSSGG (pairs in the middle with outer grounds)
Add via fences near BTB to lower return-path impedance and crosstalk in high-speed designs.
Connector Contact Materials & Plating
Base Metals (Contacts)
| Base Metal | Strength / Spring | Cycle Life | Cost Level | Typical Use |
|---|---|---|---|---|
| Brass | Medium | General purpose, lower cycles | ||
| Phosphor Bronze | High | Balanced choice for headers/receptacles | ||
| BeCu | + | + | Very High | High cycle, shock/vibration environments |
Plastic Insulators
Insulators hold contacts in shape and define mechanical, thermal, and flammability performance.
| Material | UL 94 | Reflow/Temp | Moisture | Notes |
|---|---|---|---|---|
| PBT | V-0 | ~230 °C short-term | Low | Stable & economical for TH/SMT |
| PA66 | V-0 | ~250 °C | Medium | Tough; needs moisture conditioning |
| PA46 / PA6T | V-0 | ~290–320 °C | Low–Med | SMT-grade; high-temp stiffness |
| LCP | V-0 | ~290–320 °C | Very Low | Excellent dimensional stability; fine-pitch friendly |
Typical MSL: 1 (material dependent). LCP/PA6T suit fine-pitch and lead-free reflow.
Packaging Options
Select packaging that matches your assembly flow, ESD control, and traceability needs.
| Option | Best For | Pros | Notes |
|---|---|---|---|
| Tape & Reel + Pick & Place Cap | SMT, high volume | Fast placement; protects contacts | Check tape cavity/orientation; 13″/15″ reels common |
| Tube / Tube + Cap | TH or mixed | Economical, simple handling | ESD control; feeder compatibility |
| Tray (JEDEC) | Large or delicate parts | Good protection; easy counting | More storage space; label lot/date for traceability |
| Bulk / Custom | Prototypes, special kits | Flexible | Add ESD shielding and documentation as needed |
Power Board-to-Board Connectors
For power delivery, choose larger pitch and contact sections to reduce temperature rise and improve reliability.
- Thicker contacts & robust plating (Ni underplate with hard gold or tin)
- Derating for ambient temperature and PCB copper thickness
- Separate grounds/shields for low-impedance returns
Fast rule: Total current ≈ power pins × current per pin × 0.7
High-Speed Board-to-Board Connectors
- Target impedance: 85 Ω (SAS/PCIe) or 100 Ω (Ethernet)
- Control pair-to-pair skew & crosstalk via geometry and shields
- Use pad/anti-pad tuning and keep-outs under the connector to reduce stubs
- Validated up to 28 Gbps in suitable topologies (application-dependent)
