TPSI3050-Q1: fails

Norman Werner

Part Number: TPSI3050-Q1
Other Parts Discussed in Thread: TPSI3050,

Tool/software:

I use a TPSI3050 to enable a capacitor-discharge FET. This FET is preceded by a ~0.2A current limiting circuitry.

At higher voltages (~300V) this will lead to failures of TPSI3050. Resistance (as measured by DMM) between Pins VDDM und VSSS is ~11Ohms afterwards.

Seemingly FETs are not destroyed and substitution of TPS3050 will repair ciruitry.

TPSI3050 is used in 3-wire mode. Ub=4.7V, Rp=9K09

Currently I am running out of samples for repairing/troubleshooting the issue so any clue would be very welcome.

Attached is a simplified schematic.

7 months ago

0 Hussain Alsahhaf 7 months ago

TI__Intellectual 1530 points

Hello Norman,

Thank you for reaching out to our team's E2E and for sharing the schematic for your capacitor discharge application with TPSI3050-Q1.

Sorry to hear that you are running out of samples, our team is reviewing your request and will be in touch on the next business day.

Thank you again for your patience as we help debug.

Best regards,

Hussain

0 Tilden Chen 7 months ago

TI__Genius 9211 points

Hello Norman,

Thanks for reaching out to our team on E2E.

I wonder if transient is coupling from drain-to-gate and damaging TPSI305x driver, try adding TVS from gate-to-source to help clamp the voltage below 20V and see if this helps.

Best regards,
Tilden Chen

Solid State Relays | Applications Engineer

0 Norman Werner 7 months ago in reply to Tilden Chen

Prodigy 70 points

This was my least improbable guess as well.

I ended up, adding a pretty highish gate resistor and a clamping diode to prevent negative voltages at the gate. This resolved my problem - however I didn't get any insight about failure mechanism.

Power management

Power management forum

TPSI3050-Q1: fails