مديول GSM بنطاق ترددى 900 / 1800 MHz SIM900A SIM900 GSM GPRS Wireless Extension Module

Size:50mm x 48.3mm
The serial port circuit: support for 3.3V single chip microcomputer. TTL serial port support
3.3 and 5V single chip microcomputer.
The SIM card circuit to increase the SMF05C ESD chip.
Two power supply interface: VCC5, 5V DC above 1A. Computer 5V power supply can be early computer USB. DC long data circuit over larger recommended 5V1A. VCC4, 3.5–4.5V power supply, ibid., suitable for lithium battery.
Control pin all leads.
A TTL level, compatible with 3.3V and 5V.
The two antenna interface, the default SMA straight head, connector for IPXmini antenna.
One way of speech interface, the way Mike interface.
Serial port circuit(with protection)
Antenna interface circuit(SMA bend female port)
SIM card circuit(flip SIM slot)
4*3.5 fixture hole 4pcs