TPS2595: ESD protection

Hi Hirokazu,

1. Regarding ESD strategy I think we can't share because that is confidential info. Why is that info important for customer?

2. Do you want to know how device will behave when we short VIN to GND or VOUT to GND?  When we short VIN to GND device will turn off and we don't expect it to break. When you short VOUT to GND then device will quickly limit the current , when it does that then there can be positive transient at input and negative transient at output that can exceed device abs max voltage rating. So we recommend using TVS at input and schottky diode at output for  suppressing transients.

Regards

Kunal Goel 

Hello Kunal-san

Thanks for your reply.

They found some leakage between VIN and GND after the evaluation.

But we are not sure the actual root cause.

They want to know TPS2595 has the ESD protection circuits in each pins or not.

It isn't necessary to explanation the detail protection structure.

Best Regards,

Hirokazu Takahashi

Hi Hirokazu,

When is current leakage happening ? What is test condition? How much is leakage value? Do customer think they violated ESD ratings ?

Regards

Kunal Goel

Hello Kunal-san

Thanks for your reply.

When they measured some waveform at the point with oscilloscope, the fail happed.

Pin 2 EN/UVLO has leakage, the detail is uncleared. 

Their question is simple, ESD protections is built or not in each pins. Please let me know it.

And I got one more question below.

If Vout shorted to GND, is it potential to break EN/UVLO pin?

Best Regards,

Hirokazu Takahashi

Hi Hirokazu,

I need to check with design team on ESD. This can take some time.

Regarding VOUT short to GND, if you don't have transient protection at VIN side and EN is pulled to VIN then voltage spike can exceed abs max of EN pin and damage EN pin. How is EN connected in customer system?

Regards

Kunal Goel

Hello Kunal-san

Thanks for your reply.

EN/UVLO is connected to IN with 1MΩ in their system.

IN -- (1MΩ) -- EN/UVLO -- (330kΩ+56kΩ) -- GND

Best Regards,

Hirokazu Takahashi

Hi Hirokazu,

ESD protection diodes are on all pins.

Regards

Kunal Goel

Hello Kunal-san

There aren't further question.

Thanks a lot.

Regards,

Hirokazu Takahashi