TPS25947: For switch design related problems

Lance Wu

Part Number: TPS25947
Other Parts Discussed in Thread: PCA9535

Dear TI:

I want to design a power switch circuit with TPS259470,But Some Question：

1.My Circuit Designe

EN/UVLO Connect to PCA9535, GPIO Level is 5V,TPS259470 is controlled by I2C bus;When GPIO =H,TPS259470=ON,GPIO = L TPS259470=OFF;

OVLO Connect to GND;Close Overvoltage Clamp

2.Since my GPIO input is 5V, the input voltage of TPS259470 changes from 3-18V, and the EN/UVLO voltage is higher than the input voltage of TPS259470, is there any problem in this design?

3.OVLO is connected to GND to close the Overvoltage Clamp. Is there any problem with this design?

I would like to ask TI engineers to help answer the above questions!Thanks

3 天前

0 Eric Ba 3 天前

TI__Intellectual 1960 points

Hi , it is ok to use like this. These 2 pins are buffered, there will be no leakage current.

0 Lance Wu 2 天前回复 Eric Ba

Prodigy 30 points

Thank you for your answer, which will be helpful to me. I have another question. If I connect a digital potentiometer to the ILM PIN for variable current clamp, use I2C communication to change the current clamping,there should be no problem according to the internal structure of the chip, and the resistance needs to be set before the input of TPS259470 to ensure effective current limiting. Is this understanding correct?