STUSB4500QTR Stops working

[Ner]

Hi,

I am trying to use STUSB4500QTR in a new board.

In my design, the STUSB4500QTR is supplied from a USB-C power adaptor. The application intended for use of 20V supply.

When connecting the adapter to USB-C port for first time, there is 20V on output of power delivery circuit.

After repeated disconnection and connection of power adaptor from USB-C (from 2 to 7 cycles). The STUSB4500QTR stops working.

Measuring the circuit, after that, I found that there is not voltage on VREG_2V7 pin (pin #23) and resistance of it to ground is very low (1.6 Ohm).

This happens even if there is no load connected to power delivery circuit output.

This issue happened on at least 3 STUSB4500QTR components.

Please advise: what could be causes of this? how to solve this issue?

[AScha.3]

Hi,

can you show your circuit ? Otherwise just groping in the fog ...

[Ner]

Hi,

Please see attached schematic.

Thank You.

[AScha.3]

Only thing i see: you have no protection on CC lines...(if that would be important..?)

Might be the reson, some static ESD could come to the chip , i would try to add this ESDxxx .

[Ner]

Hi,

Thank you for you comment.

I have U52 part (TI P/N: TPD4E05U06DQA) as protection device on CC lines.

Is that enough?

[AScha.3]

Oh - sure, i didnt realize. 

So just from your description : plug in - out ...then dead, is typical for some ESD or so.

btw

I killed a Raspberry Pi, just by plugging in the HDMI cable+monitor, didnt power away from everything, so the monitor was connected to (mains) ground, Pi was off (sure, i always try to be careful), but the active speakers still connected to Pi, and that SMPS had the usual 2nF to reduce EMI - and this might be charged to mains voltage and discharge on connection to ground...the hdmi-input of the Pi. Black screen then...for all time from this Pi.

But you should (!) have good ESD protection, so ...

just: is anything else "different" on the dead boards , esp. the ESD diodes still same as before ?