This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS23880: Question about TPS23880 Surge Protection Component

Part Number: TPS23880
Other Parts Discussed in Thread: TPS23861

Hello, TI Team Members,

     I have seen the TPS23861 four port lightning surge board schematic as a reference guide for TPS23880 surge protection. And  I have a query about  line side MOV V14E230P which show as RV1 to RV4 on schematic.   Why did you  chose  V14E230 as the MOV which clamping voltage at AC 230V and location from VR1 to VR4? Can we use DC 58V TVS to replace it?  And why did you use two kinds of TVS at PHY side which part named TCS-DL004-250-WH and CDSOD323-T05C? Can we use only one kind of it? Thanks! 

 

TPS23861 6Kv PSE PR2189E1_SCH.PDF

  • Hi Cheng,

    These MOVs are selected based on the current. The Littlefuse V14E230P, V10E230P, and V07E230P were selected for port 1 (75 A), port 2 (50 A), and port 3 (25 A), respectively.The MOVs may not be required for test levels up to 1000 V because the IEEE 802.3 standard specifies that the PSE must have a withstand strength of at least 1500 VPK for the 10/700-µs impulse test. This is the case for port 4 above and for this case the guidance provided in Electrical Transient Immunity for Power-Over-Ethernet will be used. If the PSE port has been designed with a withstand rating per the 1500 VRMS or 2250 VDC rating specified in the IEEE 802.3 standard then the MOVs may not be required for the 2000-V test level. For this design example, MOVs will be used for port 3. The MOVs would definitely be required to meet test levels that exceed the withstand strength of the PSE, which in most cases would include the 4000-V test level and certainly the 6000-V level. MOVs will be used also for port 1 and port 2 to illustrate the design and selection procedure.

    On the data side, CDSOD323-T05C is the transient voltage suppressor and TCS-DL004-250-WH is the transient current suppressor. I think you will need both but you had better to consult with your PHY vendor and see what they recommend for the data line protections. Thanks.

    Best regards,

    Penny