Adafruit Ultimate GPS power by arduino digital output Issues

[terry01000]

I used Arduino digital output (D2) to supply the 5V on the Adafruit Ultimate GPS. The system function. However, I found that it's very difficult to get a fixed. The GPS can found fixed much better if connect to 5V directly. In my application, I turn off power to the GPS once a location is found to save power.
The question are:
Can we use Arduino digital output as GPS power source ?
Is there any particular reason that power from Digital output cause some issue with GPS operation?

Thanks in advance for your thoughts,
Terry

[adafruit_support_mike]

The GPS module needs more current than an Arduino pin can supply.

The GPS module can boot, but the radio won't have enough current to get a fix.

[terry01000]

Thanks for the input.
If I understand correctly, this GPS use 20ma. The arduino digital I/O can supply 100 ma.
Did I make the wrong assumption ?
What is the proper way to power the GPS ?
To conserve battery,
Should I use an relay ?
Is setting GPS to standby mode a good option?
Thanks,

[adafruit_support_mike]

An Arduino’s GPIO pin has an absolute maximum current of 40mA. The limit for the entire microcontroller is 200mA. It’s generally best to avoid drawing more than 30mA from a pin, because ‘absolute maximum’ means “if you exceed the limit and the chip dies, don’t blame the manufacturer.”

The GPS module uses about 20mA when it has a fix, but needs 40mA to 45mA to acquire a fix.