LM5576: LM5576Q tested data

Muthu S

Part Number: LM5576

Hi,

We did it testing for TI Buck LM5576Q IC the operate and failure condition is given below. It should with stand up to 70V Minimum but it is failed Supply voltage at 60V.

Supply Voltage : 60V

Output Voltage : 12V

Output Current : 225mA.

Operating Temperature : 25⁰C

Observation:

Momentary spark was observed around the pins 3,4,5,6 of the regulator IC during failure
Output was cut-off after failure and Input consumed ~0 A current
Buck Regulator Failure : Resistance between output pin of Buck regulator and respective GND was observed to be ~300 Ohms

Impact of buck regulator failure:

MOSFET Gate driver IC flailed
5V LDO Failed.

Please provide High voltage condition test date which you made it (TI –Tested data)

Regards,

Muthu S

over 6 years ago

0 Arief Hernadi over 6 years ago

TI__Mastermind 23845 points

Hi,

Do you have schematic and layout for your design?

Thanks

0 Muthu S over 6 years ago in reply to Arief Hernadi

Intellectual 720 points

Hi Arief,

Please find attached schemtaic and layout details. Please verify and share your feedback.

Regards,

Muthu S

0 Arief Hernadi over 6 years ago in reply to Muthu S

TI__Mastermind 23845 points

HI,

Do you have the waveform of VIN during startup at C39? I would like to check if there is no spike or overshoot at this pin during startup.
After looking at the layout, do you know where is the connection from the input capacitor GND (C39) goes back to IC PGND? Is there a via there?

Also when the parts fail, is the diode also fail? What is the part number for the diode used in this application? Could it handle at least 3A of current?

Thanks
-Arief

0 Muthu S over 6 years ago in reply to Arief Hernadi

Intellectual 720 points

Hi Arief,

Thank you for your email, Comments given below for your reference.

Input side we have TVS diode there is no chance to over voltage. As of now we don’t have waveform.

C39 GND and PGND PAD connected through via, also we provided GND Layer for the same.

Diode used (D41) 1N4007 Rated 1A,But pulse Current is 30A 8.3ms. Diode not failed,

D8 30V 5A(FSV530AF)

D7 100V 4A (NRVTSA4100ET3G)

Regards,

Muthu S

0 Arief Hernadi over 6 years ago in reply to Muthu S

TI__Mastermind 23845 points

Hi,

It looks like your D8 is lower voltage (30V) and if your input voltage is 60V then most likely you will damage this diode,
i recommend using a 100V diode as D7 and see if it helps

Thanks
-Arief

Power management

Power management forum

LM5576: LM5576Q tested data