SJA1110 Multi-gig safe and secure TSN Ethernet switch ESD clamping voltage.

[bdudemon]

Hi,  I'm trying to project SJA1110 in a harsh ESD environment and for me to do so I need to understand at what voltage levels on the 100Base-T1 interface which is the TRX_P and TRX_P pins.  Understand that your part's ESD protection will never withstand the threat I dealing with therefore I need my TVS device(s) to activate before your part tries to take the hit and basically blows up in the process of trying to do so.  So relative to a TVS specification, at what voltage level is your ESD protection fully clamped (maximum current peak).   Again I only want to understand this to ensure my TVS devices will clamp the power before your switch does.

[PavelL]

Hello Brandon,

According to SJA1110 Hardware Application Note  chapter 5.1.6.1, external ESD suppression devices according to IEC62228-5 and SAE2962-3, e.g. PESD2ETH1G-T, can be used if extended ESD robustness beyond 15 kV air discharge is required.

Nevertheless, harsh ESD environment sounds to me like repetitive events, not only single ESD event. In that case, your clamp shall keep voltage within range of limiting values -0.3V to +4V, according to Datasheet and Errata Sheet SJA1110 Table 22.

I see what value you are requesting. I understand that TLP curve is measured only on dedicated test vehicles where ESD IP is being developed. It is not measured on final products, nor guaranteed in production. Naturally, final products have to pass all ESD requirements.

Best regards,

Pavel