I am going to buy A6 GSM module for connecting to my Raspberry PI and making a little research here. Will I be able to power up this module purely from PI or external power source is a must?
A6 data specification says it requires from 4.9 to 9 volts.
Can it be powered up, for example, from GPIO port, which seem to be provide 5V? Some sources say about 5V battery, but maybe it's just a a recommendation?
I am totally newbie in electronics and had no experience with PI before. I have Raspberry PI 2 model B revision 1.1.
UPDATE: I found out that module specified in my first link is not actually a SIM900 module so I corrected the title. It is A6 tagged as a replacement of SIM900 and seems to be based on GSM/GPRS A6 chip.
Also in the web I found several modifications tagged both as SIM900 and A6 (1, 2, 3), and all of them have different power consumption (1.3mA, 1.5mA, 2mA). As I have no particular preference in one GSM module over another during the purchase, opinions on any of them are appreciated. Real experience is highly appreciated.
Best Answer
It all depends on your power supply. The module seems to use about 1A (from the source you linked). If you are powering the Pi from a 2A microUSB connection as recommended, and you don't have any other peripherals (e.g. a Wi-Fi dongle), then yes, it is okay to power it from the 5V pin on the GPIO header. What another user posted about was the generic GPIO pins. These provide ~20 mA @ 3.3V, and can be switched by software. You would not use these, but the dedicated 5V port on the module.