[FAQ] TPS23861: Can Rsense be modified to achieve higher current limit (>920mA)?

The current measurement is based on measuring voltage across the sense resistor.  We can select the sense resistance through register 0x17(255mΩ or 250mΩ). Theoretically higher current limit can be achieved by reducing the sense resistance. However, the classification current is also measured through the sense resistor.  If customer doesn’t have the control of the PD side, it will cause interoperability issue with other standard PDs. If customer has the control of both PSE and PD side and their PSE has no chance to connect to other PDs, the detection resistance and class resistance should be modified accordingly  to ensure the measured detection resistance and class current are within the acceptance range of TPS23861.

Additional Resources

• Check out TI's PoE landing page: www.TI.com/PoE

• Learn about the IEEE802.3bt standard: Power over Ethernet: Getting Started with the New Standard