SLVAF74 July   2021 TPS2372 , TPS2373 , TPS23730 , TPS23731 , TPS23734 , TPS2375 , TPS2375-1 , TPS23750 , TPS23751 , TPS23752 , TPS23753A , TPS23754 , TPS23754-1 , TPS23755 , TPS23756 , TPS23757 , TPS23758 , TPS2376 , TPS2376-H , TPS2377 , TPS2377-1 , TPS23770 , TPS2378 , TPS2379

 

  1.   Trademarks
  2. 1Introduction
  3. 2Preparation and Measurement Techniques
    1. 2.1 Important PoE Signals
    2. 2.2 Lab Equipment
    3. 2.3 Measurement Techniques
    4. 2.4 Board Preparation
  4. 3Narrowing Down the Problem Area
    1. 3.1 Schematic Areas
    2. 3.2 Narrowing Down the Area On Board
  5. 4Common Issues
  6. 5Conclusion

2.2 Lab Equipment

The following list is not exhaustive, but these items are all useful. Not all equipment is required for every debug:

  • DC power supplies
  • Electronic load
  • Oscilloscope with four channels and probes
  • Current probe
  • Differential probe
  • Resistive load
  • Digital multimeters (as many as your bench holds)
  • Ethernet cable – standard Cat 5
  • Ethernet cable – split open, banana female connectors soldered to twisted pair sets such that a DC power supply can power through these twisted pairs
  • Grabber to banana wires
  • IEEE802.3 certified Power Sourcing Equipment (PSE) – TPS23881 EVM recommended
  • Bode box or equivalent for gain or phase measurement loop response
  • Sifos® PDA-602 analyzer