TPS73001 regulator fault

[arieblum]

Hello all

The problem:
The TPS73001DBVR regulator fail in 3 boards out of 20 boards -> output is zero
I replaced it and it is working now

The circuit:
By the book, input voltage, output current in the data sheet limit
The regulator located at the input of the board ans it received the input from other circuit

My question:
1) What can be the reason? ESD? or else?
2) what can I do to prevent next fault (now, with present layout and later, at the next layout)?

Arie

 

[KlausST]

Hi,

The circuit in the datasheet surely works.

But YOUR circuit fails.
Therefore - if you need help - give us YOUR schematic and YOUR PCB layout. And all technical informations...

2) what can I do to prevent next fault (now, with present layout and later, at the next layout)?

Follow the design rules and the specifications given in the datasheet. That´s all.

1) What can be the reason? ESD? or else?

If you look into the datasheet, then yo will find a lot of specifications. All with values and units.
But in your post there is not a single value and not a single unit.
--> it is impossible for us to decide what can be the problem.

So give us YOUR data:
* input voltage (best: min, max, avg)
* output voltage (desired, measured)
* output current (average, peak)
* what´s the load? Switched? HF?
* are inductors involved?
* what capacitors do you use?
* temperature after a while of operation.

Klaus

 

[arieblum]

Thank you very much Klaus for your quick and full answer
I am sure data sheet is working and I am now check it all as you suggested
but if sombody had the same fail and he worked hard to find the reason (that is not the regular high input voltage etc.) it maight short my time...
Arie