TPS7A25: Power management forum

Intellectual 460 points

Part Number: TPS7A25
Other Parts Discussed in Thread: TLV741P

Hi TI,

1.) I would like to know can TI provide Output current limit graph like below for TPS7A25?

Below graph are taken from TLV741P datasheet

2.) The Output current limit written in datasheet is Min:325mA Typ:510mA Max:720mA

May I know any possible scenario will trigger the current limit exceed 500mA?

Thanks,

over 6 years ago

0 JCHK over 6 years ago

TI__Guru 50190 points

Hi ZY,

The TLV741P has a foldback current limit whereas the TPS7A25 has what we call a brick-wall current limit. What this means when a short occurs, it will be limited to a limit in the range you list above. When a device is in current limit, it means that the load is drawing more current that we are allowing the device to supply so the net result is VOUT will typically fall. As VOUT falls, the power dissipation across the device increases and typically leads to a thermal shutdown.

Now to answer your question on the possible scenarios to enter current limit, this could be either there is too much current drawn by the load or a short at the output of the LDO.

I hope this answers your question.

Regards,

0 ZY over 6 years ago in reply to JCHK

Intellectual 460 points

Thanks for the reply. Well noted on question 1.

For Question2:

Any other document from TI can guarantee the current limit to 500mA only instead of 720mA?

This is because my customer application spec requirement only allow to limit current between 300mA -500mA only. Anything exceed 500mA will possible introduce defect to the application.

Thanks and Regard,

0 JCHK over 6 years ago in reply to ZY

TI__Guru 50190 points

Hi ZY,

Our TPS709 has a maximum current limit of 500mA, but the minimum current limit is at 200mA. Can this work for you?

Let me know.

Thank you,