Backplane Connectors - Hard Metric, Standard

Image	Part Number	Description / PDF	Quantity	Rfq
	PCN21B-55SCA-2PF Hirose	CONN RECEPT 55POS 2MM PRESS-FIT	0
	HP6-252S-1.27DS(04) Hirose	CONNECTOR	0
	HP6-123(26)S-1.27DSB(04) Hirose	CONNECTOR	0
	PCN21B-125PB-2W-G Hirose	CONN HEADER 175POS 2MM PRESS-FIT	0
	HP5-??????189B(189G) Hirose	CONNECTOR	0
	HP6-252S-1.27DS(78) Hirose	CONNECTOR	0
	PCN21B-95PB-2W-G Hirose	CONN HEADER 133POS 2MM PRESS-FIT	0
	HP5-252P-1.27W(04) Hirose	CONNECTOR	0

Backplane Connectors - Hard Metric, Standard

1. Overview

Hard Metric Standard Backplane Connectors are precision-engineered electrical components designed for high-density interconnection in complex systems. Defined by their standardized 2.54mm (0.1") grid spacing, these connectors ensure mechanical and electrical compatibility across generations of equipment. Their importance in modern technology stems from enabling scalable, high-reliability architectures in telecommunications, industrial automation, and mission-critical computing systems.

2. Main Types & Functional Classification

Type	Key Features	Applications
2.54mm Hard Metric	Standardized pitch, 1-6 rows, up to 60A per contact	Telecom switches, industrial controllers
2.00mm Hard Metric	Reduced pitch, enhanced vibration resistance	High-density servers, medical imaging
1.27mm Hard Metric	Ultra-high density, low insertion force	Compact test equipment, aerospace systems

3. Structure & Composition

Typical construction includes: - Insulating housing (LCP/nylon with high thermal stability) - Contact array (phosphor bronze with gold/silver plating) - Polarization keying for mating assurance - EMI shielding via integrated metal frames - Actuation mechanism (lever-assisted or push-pull variants)

4. Key Technical Specifications

Parameter	Typical Value	Importance
Current Rating	1-60A per contact	Determines power delivery capacity
Contact Resistance	5m	Impacts signal integrity
Dielectric Strength	1000VAC	Safety and insulation reliability
Mating Cycles	200-2000 cycles	System longevity indicator
Operating Temp	-55 C to +125 C	Environmental robustness

5. Application Fields

Telecommunications: 5G base stations, optical transport systems
Industrial: PLC backplanes, test & measurement equipment
Medical: MRI scanners, diagnostic imaging systems
Transportation: Rail signaling systems, avionics

6. Leading Manufacturers & Products

Manufacturer	Product Series	Key Features
TE Connectivity	HERMHARD HM	2.54mm, 3-row, 3000V isolation
Amphenol	HarshIO HM	IP67-rated, extreme vibration resistance
Molex	MX Hard Metric	High-speed differential pairs, 25Gbps

7. Selection Guidelines

Key considerations include: - Electrical requirements (current/voltage per contact) - Mechanical constraints (board spacing, mating force) - Environmental conditions (temperature, vibration) - Future scalability (modular design compatibility) - Cost optimization (total lifecycle vs upfront cost)

8. Industry Trends

Emerging developments include: - Integration with optical backplane technology - Increased adoption of 1.27mm pitch for compact systems - Enhanced thermal management solutions - RoHS-compliant plating materials (replacing cadmium) - Smart connectors with integrated diagnostics