Texas Instruments TPS23861PWR

The TPS23861PWR from Texas Instruments is a highly integrated, IEEE 802.3at compliant Quad Port Power-over-Ethernet (PoE) Power Sourcing Equipment (PSE) controller. This device is designed to manage four PoE ports autonomously, eliminating the need for external control or initial I²C communication. It automatically detects, classifies, and powers devices according to the IEEE 802.3at standard, making it a robust solution for various PoE applications.

• Automatic Operation: Automatically detects, classifies, and powers devices without the need for external control or initial I²C communication.
• IEEE 802.3at Compliance: Fully compliant with the IEEE 802.3at standard, supporting Type 1 and Type 2 Powered Devices (PDs).
• Efficient Current Sensing: Uses a 255 mΩ sense resistor with Kelvin current sensing for accurate load current measurement.
• Two-Layer PCB Design: Pin-out enables two-layer PCB designs, reducing complexity and cost.
• I²C Control: Supports Semi-Auto Mode via I²C control for precision monitoring and intelligent power management.
• Fast Shutdown Mode: Responds quickly to shutdown commands with a reaction time of typically 2 µs.
• A/D Converters: Features five multi-slope integrating converters for current and voltage monitoring, including port voltage, current, and temperature measurements.
• Interrupt and Watchdog Timer: Includes programmable timer-deferrable interrupts and an I²C watchdog timer to prevent hazardous states.

The TPS23861PWR is suitable for a variety of Power-over-Ethernet (PoE) applications, including:

• Network Switches and Routers: Enhances power management in network infrastructure devices.
• IP Phones and Cameras: Powers IP phones, cameras, and other PoE-enabled devices.
• Wireless Access Points: Supports the power requirements of wireless access points.
• Industrial Automation: Used in industrial settings for powering devices over Ethernet.
• Smart Buildings and IoT Devices: Ideal for powering IoT devices and smart building infrastructure.

1. What is the TPS23861PWR and what standard does it comply with?

   The TPS23861PWR is a Quad Port Power-over-Ethernet (PoE) Power Sourcing Equipment (PSE) controller that complies with the IEEE 802.3at standard.

2. How many ports does the TPS23861PWR support?

   The TPS23861PWR supports four PoE ports.

3. What is the typical supply voltage range for VPWR?

   The typical supply voltage range for VPWR is 44 V to 57 V, with nominal values of 48 V or 54 V.

4. What is the purpose of the 255 mΩ sense resistor?

   The 255 mΩ sense resistor is used for accurate load current measurement with Kelvin current sensing.

5. Does the TPS23861PWR support I²C communication?

   Yes, the TPS23861PWR supports I²C communication for Semi-Auto Mode and other control functions.

6. How does the TPS23861PWR handle shutdown commands?

   The TPS23861PWR responds quickly to shutdown commands with a reaction time of typically 2 µs in Fast Shutdown Mode.

7. What types of A/D converters are used in the TPS23861PWR?

   The TPS23861PWR features five multi-slope integrating converters for current and voltage monitoring.

8. Does the TPS23861PWR have any watchdog timer functionality?

   Yes, it includes an I²C watchdog timer to prevent hazardous states and ensure system reliability.

9. What are some typical applications for the TPS23861PWR?

   Typical applications include network switches, IP phones, wireless access points, industrial automation, and smart building infrastructure.

10. How does the TPS23861PWR handle legacy devices?

    The TPS23861PWR can be configured to detect or ignore legacy PD devices not compliant with IEEE 802.3at through the LEGMODn fields.