LMR14020: FTA

Kuramochi Tadahiko

Guru 28715 points

Part Number: LMR14020

Hi,

My customer is concerning FTA of LMR14020.

Could you tell me the cause not functioning below ？

・Thermal Shutdown

・Over current protection

Best Regards,

Kuramochi

over 7 years ago

0 Edwin Zang over 7 years ago

TI__Expert 6425 points

hello

I'm confused about what do your question. Why can the IC happen thermal shudown or over current, or what's behavior of thermal shutdown?

Best regards,

Edwin.

0 Andy Chen over 7 years ago

TI__Mastermind 34875 points

Hi Kuramochi

Do you mean what's casue for the function not working?

0 Kuramochi Tadahiko over 7 years ago in reply to Andy Chen

Guru 28715 points

Hi Chen-san,

Yes, You're right.
We would like to know the guessable cause if OCP and thermal doesn't working.

Best Regards,
Kuramochi

0 Andy Chen over 7 years ago in reply to Kuramochi Tadahiko

TI__Mastermind 34875 points

Hi Kuramochi-san,

The control circuit can't turn-off high-side switch during Ton-min time even the current peak is higher than maximum current limitation which means the OCP fuinction doesn't work in this case. thermal protection is always working as long as the device is active.

0 Kuramochi Tadahiko over 7 years ago in reply to Andy Chen

Guru 28715 points

Hi Andy-san,

I have an additional question.
When temperature rise up by operating thermal shutdown, is there a possibility of not functioning OCP?

Best Regards,
Kuramochi

0 Andy Chen over 7 years ago in reply to Kuramochi Tadahiko

TI__Mastermind 34875 points

Kuramochi-san,

The switching current is limited cycle by cycel as LMR14020 operates in peak current control mode, the high side current limit goes lower when junction temp goes high for better reliability. so the OCP feature keeps functioning as lomng as the chip is active before thermal shutdown.

Power management

Power management forum

LMR14020: FTA