TPS61071: Component failure

William Hanna

Part Number: TPS61071

I have had 3 failures out of 10 units with the TPS61071DDCR boost converter. The device is failing and shorting VOUT to ground and drawing about 1A from the power supply with ~0V output. The supply to the converter is controlled by a MCU switched HS MOSFET. Some of the devices have been through 100's of power cycles without a failure. Once replaced failed devices the replaced device seems to work consistently. Supply is from a 3.5V Lithium battery or when testing a 3.1V bench supply. There don't appear to be any special power-up requirements in the datasheet and general guidelines have been followed.

Any thought on reasons for failure?

over 5 years ago

0 Minqiu Xie over 5 years ago

TI__Mastermind 21565 points

Hi Wiliam:

May you share more detail information to us?

Such as :

1. The layout.

2. The waveform of Vin, Vout, SW with load.

3. Please check if it soldering well.

0 William Hanna over 5 years ago in reply to Minqiu Xie

Prodigy 20 points

Hi Minqiu,

Below is screen shot of layout top layer, has solid ground plane underneath.

Do you want those waveforms at startup or just under maximum load, etc?

Soldering is good.

Thanks,

William

0 Minqiu Xie over 5 years ago in reply to William Hanna

TI__Mastermind 21565 points

Hi William:

Thanks for your sharing. According to the layout, I afraid the road from Vin to inductance is terrible. There is a large ripple following the inductance, and it will influence other signal. I'll strongly recommend you follow the Layout Guidance of the datasheet, together with the design of Cout.

Please add the waveform with load, to check if it the cause root which damage the IC. Otherwise, we may need do further deeper analysis.

0 Minqiu Xie over 5 years ago in reply to Minqiu Xie

TI__Mastermind 21565 points

Hi William:

I wonder if there is anything else I could support. Is there anything updating?

0 Minqiu Xie over 5 years ago in reply to Minqiu Xie

TI__Mastermind 21565 points

Hi William:

How is it going? I'll close the thread as I assumes you had solved the issue. if not, just reply below.

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TPS61071: Component failure