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.

TPS23754EVM-420: ESD protection by DRTN

Part Number: TPS23754EVM-420
Other Parts Discussed in Thread: TPS23754

Hi team,

Looking at Figure 1 in TPS23754EVM-420 user's guide, there is TVS diode (D18) on the schematic.

According to TPS23754 datasheet 8.2.2.2, D18 is used for an additional protection from ESD.

It should protect ARTN,COM,RTN pins from transient voltage apilied to Vss. Customer wants to check about more detail for it.

1) Were there any issues in the past without TVS diode between Vss-GND?

2) What any specific situations is this TVS diode needed?

Regards,

Saito

  • Hello Saito,

    Thank you for your question. So D18's purpose is to protect the internal pass MOSFET that exists between VSS and RTN. This TVS diode adds robustness to the EVM to protect in surge situations.

    D18 is not required, and was not added due to a particular issue. The voltage rating for the internal FET is 100V, so it is the customer's decision if they think a surge event is likely to happen over this voltage. And does the customer want to address the unlikely case when a surge of 100V+ does happen, can the board handle it. 

    Section 6.2 ESD Ratings gives some voltage levels for common surge events, which are all above 100V. So, ultimately it is the customer decision to have, i have seen designs with and without.

    Regards,

    Michael Pahl