TPS61170: Short protection

Kunal barot

Part Number: TPS61170
Other Parts Discussed in Thread: PMP9779

Hi Support

we are using TPS61170QDRVRQ1 to convert 5V to 24V. while short its output (for 30sec) 24V goes 0V and when we remove the short , 24V did not recover back. Does this IC have any kind of short protection.

enable pin connected to processor.

Thanks

over 6 years ago

0 Helen chen over 6 years ago

TI__Mastermind 40080 points

Dear Sir,

TPS61170 doesn't has short circuit protection.

You can refer to TI design PMP9779 to add the short circuit protection circuit.

0 Kunal barot over 6 years ago in reply to Helen chen

Intellectual 605 points

SO what should happen even if i short the output. i have a series resistor of 3.3ohm and PTC in between. will IC go to thermal shutdown or else.

0 Helen chen over 6 years ago in reply to Kunal barot

TI__Mastermind 40080 points

Hi Sir,

The response time of the PTC is too slow. So it can't protect the IC. you can add a load switch at the output side or use the solution in the PMP9779.

0 Kunal barot over 6 years ago in reply to Helen chen

Intellectual 605 points

Hi, just want to know what will happen if i short the output, will it go thermal shut down or not.

0 Helen chen over 6 years ago in reply to Kunal barot

TI__Mastermind 40080 points

Hi Sir，

Not sure. If the current is very big, the IC may damaged before the thermal shutdown take action. If the current is not big enough, it just enters into the current limit mode.

0 Kunal barot over 6 years ago in reply to Helen chen

Intellectual 605 points

you can see attached what happen in my case , when i short 24V and current both went to zero. and when remove short they still at zero.

they only recover after power recycle.

since i have 3 .3 ohm reisotor in between so max current can be 24/3.3.

0 Kunal barot over 6 years ago in reply to Kunal barot

Intellectual 605 points

In above image blue is 24V and Green is Current, when short applied you can see peak on current.

0 Helen chen over 6 years ago in reply to Kunal barot

TI__Mastermind 40080 points

The peak current is very small, only 87mA?

0 Kunal barot over 6 years ago in reply to Helen chen

Intellectual 605 points

Peak current is not 87ma, its around 500mA, see Graph.

0 Helen chen over 6 years ago in reply to Kunal barot

TI__Mastermind 40080 points

Dear Sir,

TPS61170 doesn't support very high output current or short circuit operation , or the IC will gets abnormal or even damage. It must make sure the Vo> Vin, or it can't auto recovery after OCP .

Power management

Power management forum

TPS61170: Short protection