Maximum source current from GPIO? Can you drive opamp from GPIO?

[Noah]

Hi, I am searching the nRF52810 product spec and see that with standard drive, maximum GPIO output current appears to be 4mA. However, this spec is given for when the output of the GPIO is LOW. I want to use a TLV9061 opamp, the smallest package size that does not have a shutdown pin input, and I want to programatically chose to deliver it voltage/power it on, or not provide voltage and power it off. By doing so I can minimize current draw when I don't need the opamp to be on, compared to being routed directly to a battery supply and constantly sinking current. 

One option is to use a digital load switch, and control this this with a GPIO output, but I do not want to add more packages or components to the PCB design. The TLV opamp only takes about ~500uA current to operate, so the other potential option would be to connect the Vdd rail of the opamp directly to a GPIO from the nRF52810. Then if I set the GPIO to HIGH, would this appropriately power the opamp? I only use two other GPIO outputs in my current design, and they are both routed to high impedance pins so there is minimal current draw. It seems like powering an opamp directly through the GPIO would be a viable solution, but would like some feedback. 

I am also using nRF52810-CAAA, the WLCSP package, if that is important.

[Kenneth]

Typically I recommend using a gpio to control a mosfet to feed external circuitry (high power leds, motors and ic's) you may want to control power on/off. For instance some of these components also require decoupling capacitors, so even if the active current is ~500uA, the inrush/reverse current when turning on/off may be substantially higher.

In terms of what current you can sink and source from a gpio that is stated in the electrical specification chapter for the gpio peripheral:
https://infocenter.nordicsemi.com/topic/ps_nrf52810/gpio.html#unique_1679477596 

For instance if VDD is >=2.7V, and the GPIO is configured with high drive, then it can deliver up to 5mA in logic high. Note that the voltage out then may be as low as VDD-0.4V, to avoid the voltage drop through the GPIO I recommend to use a mosfet transistor instead.

Best regards,
Kenneth