This compact Ethernet cable is intended for embedded 100BASE-TX applications where space and connector size are constrained. It interfaces a JST GH 4-pin (1.25 mm pitch) Ethernet PHY header to a standard RJ45 (8P8C) Ethernet port. The cable is suitable for short-distance, low-noise environments such as laboratory setups, drones, or internal system wiring.

Technical Description

• Ethernet Standard: 100BASE-TX (IEEE 802.3u)
• Transmission Speed: 100 Mbit/s (full or half duplex)
• Cable Length: 200 mm ±5 mm
• Cable Type: Unshielded, custom-terminated
• Impedance Matching: Not controlled (intended for ≤30 cm use)
• Twisting: R+/R− and T+/T− signals are individually twisted as differential pairs
• Connector A: JST GH 4-pin (horizontal mount, 1.25 mm pitch)
• Connector B: RJ45 (8P8C), standard Ethernet plug, T568B-compatible mechanical interface
  

Signal Pinout (Fixed)

RJ45 pins 4, 5, 7, and 8 are left unconnected (NC).

Intended Use

• Embedded systems with Ethernet PHY routed to JST GH header
• Drones, sensor systems, and compact robotic platforms
• Ethernet breakout or adapter cable for internal assemblies
• Board-to-port bridging in test setups or low-noise enclosures

Assembly Notes

• Each differential pair (TX and RX) is individually twisted to reduce intra-pair skew and minimize crosstalk
• Not suitable for PoE (Power over Ethernet)
• Crimped and continuity-tested for reliability
• Lightweight and flexible for constrained routing paths