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TPS22981: Use as current limited load switch 12V

Part Number: TPS22981
Other Parts Discussed in Thread: TPS22918

Hi, 

I need to put a current limiting load switch after a boost converter. After a few component searches I found the TPS22981. It looks like a good candidate for this general purpose application. My current limit is 500mA, the voltage is 12V. System power is from a Li-Ion battery. There is a permanent 3.3V supply which may not deliver much current to the load during transitions to and from 12V. 

If this setup makes little sense, please suggest an available (20k/y) 12V / 500mA current limiting load switch.

Please see the attached picture below. 

Do you think this configuration will work? Is it OK to short EN to HV_EN?

From left to right: A PMOS transistor takes an active low enable signal and inverts it. This enables a boost converter and provides V3P3 to the TPS22981. Once the boost converter reaches an acceptable output level, it turns on both EN and HV_EN of the TPS22918. This connects the boost converter output to the external load. If the TPS22981 indicates thermal overload, the MCU will disable the PMOS transistor and shut everything off. 

Is VHV overcurrent indicated on FAULTZ, or is only overheating indicated?

I will set up the ISET_Sx resistors to not pull much current from V3P3. The S0 input is grounded to force S3 mode. 

Thanks,

Borge