Does anybody have experience with external power gating

[saucyboythesecond]

From what I've gathered is power gating used in IC's to prevent leakage current. this is done by implementing a high-side PMOS en low-side NMOS MOSFET and switching them opposite of each other in the following manner:

How much would you gain from using this system on a separate circuit on the pcb which has to be switched off for low power applications. I am currently looking into a high-side switch as it is easier to switch the circuit this way. Would a low-side switch reduce leakage current? or is it not worth the headache?

[gilshultz]

@saucyboythesecond

Would a low-side switch reduce leakage current?

If you have turned off the High Side where is the leakage current going to come from? I would say it is not worth the effort.

[LarryD]

• Not sure what you are needing.

• Here is a High Side power switch that is often used, no leakage.

The BJT is often charged out for a N channel MOSFET.

[saucyboythesecond]

fair enough. i have decided to use the following switch: https://www.ti.com/lit/ds/symlink/tps22916.pdf?ts=1715757524846&ref_url=https%253A%252F%252Fnl.mouser.com%252F

it has a leakage current of 100 nA, which is good for my application. it can be used high-side and low-side and can be switched using a digital 3.3V signal.

[gilshultz]

I am not following the diode from the Arduino. Should it be the other way?

[LarryD]

• The Arduino input diode is correct.

• That input pin would have its internal pull-up resistor enabled.

• The pin would be thus.
  5V——pull-up——Arduino Pin——Anode schottky diode——Cathode schottky diode——Switch——GND

• Closing the switch forward biases the schottky diode, hence 0.3V (LOW) on the Arduino input pin.