•  1. Primary side wiring:
  
  Differential pair connection: the primary side of the network transformer is connected to the differential pair of TD and RD respectively, and the line sequence of the two differential pairs can be exchanged when PCB wiring.
  
  Decoupling capacitor: The primary side should be connected to GND through a capacitor of 100nF to ensure the stability and integrity of the signal.
  
  Magnetic bead connection: For current-mode PHY, the primary coil needs to be connected with a magnetic bead, and then connected to VCC of PHY to filter out high-frequency noise and ensure signal stability.
  
  2. Secondary side wiring:
  
  RJ45 connection: the secondary side is connected to pins 1, 2, 3 and 6 of RJ45 interface.
  
  Bob Smith circuit: The secondary side should be connected with a resistor of 75Ω, and then connected to the chassis ground through a capacitor of 1nF and withstand voltage of 2KV or above. It is recommended to use a 1206-package SMD ceramic capacitor or a high-voltage ceramic capacitor with a wide pin distance.
  
  3. Grounding treatment:
  
  Suspended pin: The suspended pin of RJ45 interface should also be connected to the chassis ground through a similar design, and finally flow into the ground to ensure the integrity of the grounding system of the whole circuit.
  Circuit function description
  
  Bob Smith circuit: A circuit consisting of 75Ω resistor and 1nF capacitor, which provides a return path for common-mode signals, effectively filters common-mode signals, improves electromagnetic interference (EMI), and suppresses surge current to some extent.
  
  Decoupling capacitor: 100nF capacitor is used to filter out high-frequency noise and ensure signal stability and integrity.
  
  Voltage-resistant capacitor: The voltage-resistant value of 1nF capacitor must reach 2KV or higher to ensure the reliability in high-voltage environment.

• ---

• Product diagram-discrete product recommendation
• 
• Direct product link：
• SYT-CB4.2YGZNL、SYT60S1188AB1A6DY1008(弯脚)、SYT561188AB1A3DY1027、SYT52241188AC1A3DY1027

• Direct product link：
• WHSG24301G、WHSG24002G、WHSG48001G、WHDG72K01G

• Product diagram-integrated product recommendation

• Direct product link：
• SYT211Q106DB1A7CBS057、SYT-320DNL、SYT511Q070AB1A8D、SYT21Q042DB2A4D068

• Design reference of current-mode PHY standard-discrete
• 

• Design reference of current-mode PHY standard-integrated type

• 1. Primary side wiring:
  
  Differential pair connection: the primary side of the network transformer is connected with the differential pairs of TD0/TD1 and RD0/RD1 respectively, and the wire sequence of four groups of differential pairs can be exchanged during PCB wiring.
  
  Decoupling capacitor: The primary side should be connected to GND through a capacitor of 100nF to ensure the stability and integrity of the signal.
  
  2. Secondary side wiring:
  
  RJ45 connection: Two groups of differential signals on the secondary side should be connected to pins 1, 2, 3, 6 and 4, 5, 7 and 8 of RJ45 interface respectively.
  
  Bob Smith circuit: The secondary side should be connected with a resistor of 75Ω respectively, and then connected to the chassis ground through a capacitor of 1nF and withstand voltage of 2KV or above. It is recommended to use a 1206-package SMD ceramic capacitor or a high-voltage ceramic capacitor with a wide pin distance.
  
  3. Grounding treatment:
  
  Suspended pin: The suspended pin of RJ45 interface should also be connected to the chassis ground through a similar design, and finally flow into the ground to ensure the integrity of the grounding system of the whole circuit.
  Circuit function description
  
  Bob Smith circuit: A circuit consisting of 75Ω resistor and 1nF capacitor, which provides a return path for common-mode signals, effectively filters common-mode signals, improves electromagnetic interference (EMI), and suppresses surge current to some extent.
  
  Decoupling capacitor: 100nF capacitor is used to filter out high-frequency noise and ensure signal stability and integrity.
  
  Voltage-resistant capacitor: The voltage-resistant value of 1nF capacitor must reach 2KV or higher to ensure the reliability in high-voltage environment.

• ---

• Product diagram-discrete product recommendation
• 
• Direct product link：
• SYT-CB4.2YGZNL、SYT60S1188AB1A6DY1008(弯脚)、SYT561188AB1A3DY1027、SYT52241188AC1A3DY1027

• Direct product link：
• WHSG24301G、WHSG24002G、WHSG48001G、WHDG72K01G

• Product diagram-integrated product recommendation

• Direct product link：
• SYT211Q106DB1A7CBS057、SYT-320DNL、SYT511Q070AB1A8D、SYT21Q042DB2A4D068

• Design reference of voltage type PHY standard-discrete

• Design reference of voltage type PHY standard-integrated type

Note: The above schemes are standard designs for reference only, and the final circuit design is subject to the on-site requirements. In-depth support can be obtained free of charge for telephone consultation.

         Tel: 400-1048-018;  E-mail: wohu@wohu-tek.com;