J0C-0003NL Single Port 10/100Base-TX Ethernet MagJack Surface Mount
J0C-0003NL is a single-port RJ45 connector with integrated magnetics (MagJack) designed for 10/100Base-TX Ethernet applications.
It belongs to the PulseJack J0C series and integrates Ethernet isolation transformers and common-mode filtering inside the connector housing, simplifying PCB design and improving EMI performance.
The device uses a surface-mount (SMT) footprint and a low-profile structure, making it suitable for compact network devices such as routers, set-top boxes, and industrial controllers.
J0C-0003NL Electrical Specifications
| Parameter | Specification |
|---|---|
| Turns Ratio | 1CT:1 (TX), 1CT:1 (RX) |
| Connector Orientation | Tab Up |
| LED Indicators | Green / Yellow |
| EMI Finger | Yes |
| BST Circuit | No |
Insertion Loss
| Frequency | Insertion Loss (Max) |
|---|---|
| 1 – 65 MHz | -1.0 dB |
Return Loss (100Ω ±15Ω)
| Frequency | Return Loss (Min) |
|---|---|
| 1 – 10 MHz | -20 dB |
| 30 MHz | -16 dB |
| 60 – 80 MHz | -12 dB |
Crosstalk
| Frequency | Crosstalk (Min) |
|---|---|
| 1 – 10 MHz | -40 dB |
| 30 – 60 MHz | -35 dB |
| 60 – 100 MHz | -30 dB |
Common Mode Rejection
| Frequency | CMR (Min) |
|---|---|
| 1 – 50 MHz | -30 dB |
| 50 – 130 MHz | -20 dB |
Isolation
| Parameter | Specification |
|---|---|
| Hi-Pot Isolation Voltage | 1500 Vrms @ 60 Hz |
J0C-0003NL Mechanical Specifications
| Parameter | Specification |
|---|---|
| Connector Type | RJ45 with Integrated Magnetics |
| Port Configuration | 1 × 1 |
| Number of Contacts | 8P8C |
| Mounting Type | Surface Mount (SMT) |
| Orientation | Right Angle (90°) |
| Shielding | Shielded |
| Housing Material | High-temperature Thermoplastic |
| Contact Material | Phosphor Bronze |
| Contact Plating | Gold over Nickel |
| Height Above PCB | ~13.6 mm |
J0C-0003NL Datasheet
J0C-0003NL SMT RJ45 Connector FAQs
Q1: What is the J0C-0003NL used for?
The J0C-0003NL is used in 10/100Base-TX Ethernet interfaces where a compact RJ45 connector with integrated magnetics is required.
Typical applications include routers, switches, and embedded networking devices.
Q2: Does the J0C-0003NL include Ethernet transformers?
Yes.
The connector integrates LAN isolation transformers and common-mode filtering, which eliminates the need for external magnetics.
Q3: What Ethernet speeds does J0C-0003NL support?
The connector supports 10 Mbps and 100 Mbps Ethernet (10/100Base-TX) networks.
Q4: What type of PCB mounting does J0C-0003NL use?
The device is designed for surface-mount (SMT) PCB assembly, making it suitable for automated manufacturing.
Benefits of Using Integrated MagJack Connectors
Compared with discrete transformer + RJ45 solutions, integrated MagJack connectors like the J0C-0003NL offer several advantages:
1. Reduced PCB Space
Ethernet transformers are integrated inside the connector housing, reducing board area requirements.
2. Simplified Circuit Design
Designers can directly connect the Ethernet PHY to the MagJack interface without complex transformer routing.
3. Improved EMI Performance
Integrated common-mode filtering improves electromagnetic interference suppression.
4. Lower Assembly Cost
Fewer external components reduce manufacturing complexity and assembly cost.
J0C-0003NL SMT RJ45 Jack Conclusion
The J0C-0003NL integrated MagJack connector provides a compact and reliable solution for 10/100Base-TX Ethernet interfaces.
With built-in magnetics, strong EMI performance, and standard RJ45 connectivity, it simplifies Ethernet hardware design while maintaining compliance with IEEE networking standards.
This makes it an excellent choice for embedded networking systems, routers, switches, and industrial Ethernet equipment.
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