For the KSZ9897RTXI IC, here is a detailed circuit connection method:

1. Power Supply: Connect the VDD and RADIO pins to the appropriate power supply voltages (typically 3.3V or 2.5V) and connect the GND pins to the ground (GND) of the circuit. To provide a steady power supply, make sure the appropriate decoupling capacitors are positioned close to the power pins.

2. Ethernet Interface: The KSZ9897RTXI is an Ethernet switch IC, so it requires proper connection to the Ethernet network. Connect the MDI pins (MDI0, MDI1, MDI2, MDI3) to the corresponding Ethernet PHY or RJ45 connector pins. Follow the guidelines provided in the data sheet for proper Ethernet connection and signal integrity considerations.

3. Management Interface: The KSZ9897RTXI IC also supports a management interface for configuration and control. Connect the MDC and MDI pins to the corresponding lines of the microcontroller or host device used for management communication. Ensure that the management interface is properly implemented according to the recommended protocol (e.g., IEEE 802.3 Clause 22 or 45) for communication with the IC.

4. Additional Interfaces: The KSZ9897RTXI may have additional pins for various interfaces and features such as GPIS, interrupt outputs, LED indicators, and clock inputs. Consult the data sheet to identify these pins and connect them as per your circuit requirements.

Carefully review the pin assignments, recommended connection methods, and any additional requirements specified in the KSZ9897RTXI data sheet to ensure proper circuit operation and performance.

Please refer to the KSZ9897RTXI data sheet and application notes for accurate information on pin functionalities, recommended connections, and specific electrical characteristics. These resources provide detailed guidelines for correctly connecting the KSZ9897RTXI IC in your circuit and achieving the desired functionality.