Giới thiệu Mô Đun Truyền Dữ Liệu Không Dây Sim900a / Sim900 Gsm / Gprs
Note:Please note that this chip is second-hand chip, mind careful racket
On electricity supply
This module can be powered by lithium batteries, but remember that it must not exceed 4.8 v or burn it
About serial ports
This module is a ttl level interface, can be connected directly to single chip, arm, no need to convert devices, computer links need usb to ttl module to communicate, do not connect with serial ports such as rs232, rs485, will burn the module.
With regard to power consumption:
Shutdown current: 4ma (reset foot joint gnd)
Working current: 50ma (average)
Standby current: 20ma (jump 0~20ma)
Launch peak current: 2a (during registration)
Giá SOURCE