Features:

• Supports 5*5*2 keypads
• One full modem serial port, the user can configure two serial ports.
• One USB, the USB interfaces can debug, download software.

Specifications:

1. Operating Voltage: 3.4-4.4V DC
2. Peak Current: 2A
3. TTL serial port for serial port, you can link directly to the micro-controller.
4. Don’t need MAX232.
5. The power module automatically boots, homing network.
6. Onboard signal lights all the way.
7. It flashes slowly when there is a signal, it flashes quickly when there is no signal.

Features:

1. The onboard two set power supply interface VCC5 5V power supply, VCC4 interface, 3.5–4.5V power supply, optional power on self starting (default) and control start.
2. The onboard SMA (default) and IPX mini antenna interface, SIM900A interface reserved reset.
3. The size of the module is 49*50, all the new and original device.
4. The computer can give early computer debugging USB module power supply,
   a very large amount of data under the condition of the recommended current more than 1A.
5. Standby dozens of MA data can be set to provide dormancy, dormancy of 10MA low power.
6. The serial port circuit: support for 3.3V single chip microcomputer.