HR981191C 10/100BASE-T Magnetic RJ45 Jack with Stacked Single USB 2.0

HR981191C Datasheet

RJ45 PCB Layout & EMC Guidelines

1. Physical Isolation Shielding:

The HR981191C incorporates an internal metal partition between the upper and lower cavities. This prevents 480 Mbps USB 2.0 edge-rate switching harmonics from radiating into the sensitive 10/100 Ethernet receiver.

2. PCB Routing Separation:

• Route the USB differential pair (D+/D−) with strictly controlled 90 Ω differential impedance, keeping traces away from the Ethernet PHY signals.
• Route the Ethernet pairs (TX±,RX±) with 100 Ω differential impedance.

3. Chassis Grounding:

Connect all outer shield grounding pins directly to the chassis ground ring with wide copper planes to ensure static ESD from USB hot-plugging is shunted away from the mainboard.

Mechanical Footprint & Panel Integration Guidelines

1. Overall Outer Dimensions:

- Length (Depth into PCB): 28.35 mm
- Width (Front Face): 16.80 mm
- Height (Z-Axis Clearance): 20.90 mm
- Pin Configuration: Combined layout containing RJ45 signal leads, USB 4-pin leads, LED leads, and shield posts.

2. Panel Cutout Recommendation:

- Single Dual-Window Opening or Stepped Cutout:

• RJ45 Window: 16.20 mm width x 13.50 mm height
• USB Window: 14.50 mm width x 7.20 mm height
• Combined Front Bezel Opening: ~16.80 mm width x 21.00 mm height

- Note on Grounding: Outer shield features integrated spring tabs to ensure firm 360-degree contact with the metal enclosure.

3. Wave Soldering Envelope:

- Recommended Peak Temperature: 260°C Max
- Solder Contact Dwell Time: 5 to 10 Seconds Max

Cross-Reference RJ45 USB Combo Connectors

Technical FAQs About  HR981191C 10/100Base-T magnetic RJ45 with USB

Q1: What are the primary advantages of using the HR981191C combo connector?

The HR981191C integrates a 10/100Base-T magnetic RJ45 jack and a USB 2.0 Type-A port into a single vertical stacked package (16.80 mm width). It saves over 50% of PCB front-panel horizontal edge space, simplifies mechanical enclosure design, and reduces the bill of materials (BOM) component count.

Q2: Does high-speed USB 2.0 traffic interfere with the Ethernet signals in HR981191C?

No. The connector includes internal grounded metal shielding partitions separating the top USB chamber from the lower RJ45 magnetic transformer cavity. When combined with proper PCB grounding, this isolation prevents high-frequency USB radiation from coupling into the Ethernet receiver.

Q3: Does HR981191C support Power over Ethernet (PoE)?

No. HR981191C is a Non-PoE combo connector. The internal Ethernet magnetics are designed strictly for Fast Ethernet data transmission, while the USB port supplies standard USB bus power (5V, up to 1.5A).