The other thing to consider is that the copper traces on the pcb between the power
jack and the Vin pin, and also various ground pins, may not even be able to handle
3A without burning. Who knows? Probably best to just route power to the GSM module
Yes, I considered that. But the peaks are very very short duration (normal consumption is about 250mA)...
I have already use the sim908 in another project, the pcb tracks were very thin but the pcb has not burned (I used it for a long time). In that project I used some capacitors for a total of about 4700uF (my power supply was be able to give only 2A max).
I will try to power the gms module through the Vin pin (with also a "big" capacitor) because I'm curious now. I will let you know if I will burn Arduino Due