- V4.0 Hardware Optimization: Improved power management and signal stability compared to earlier versions, specifically designed to handle the high-current demands of GSM transmission.
- Dual-Band Capability: Operates on 900/1800 MHz, making it compatible with most GSM providers worldwide.
- Full Wireless Services: Supports SMS (text), Voice (audio interface included), and GPRS (data) for comprehensive remote connectivity.
- Universal Interface: Equipped with a standard TTL serial port (UART), allowing direct connection to Arduino, Raspberry Pi, STM32, and other 3.3V/5V microcontrollers.
- Onboard SIM Slot: High-quality industrial SIM card holder designed for durability in high-vibration environments.
- Industrial Grade: Built to operate in extreme temperatures, ensuring reliability for outdoor weather stations or factory floor monitoring.
SIM900A V4.0 GSM/GPRS Wireless Module Kit – Global Compatible with Antenna (Tested Worldwide) [Non Original]
| Model Version | V4.0 (Enhanced Edition) |
|---|---|
| Frequency Bands | Dual-Band GSM/GPRS 900/1800MHz |
| Input Voltage | DC 5V (Direct) or 3.4V – 4.4V (VBAT) |
| Peak Current | 2.0A (Required during network bursts) |
| Communication | UART Serial (TTL Level 3.3V – 5V Auto-Compatible) |
| GPRS Class | Multi-slot Class 10/8 |
| Antenna Interface | SMA Female (High-gain antenna included) |
| Operating Temp | -40°C to +85°C |




- Antenna Installation: Screw the included antenna onto the SMA connector. Warning: Do not power the module without an antenna, as it may damage the RF internal components.
- SIM Card Setup: Insert a standard-size SIM card (Mini-SIM). Ensure the card is 2G-enabled and the PIN code is deactivated.
- Powering Up: Connect a stable 5V/2A power supply. The onboard status LED will begin to blink; once it blinks slowly (every 3 seconds), it has successfully registered on the network.
- Connecting to MCU: Connect the module’s TXD to your MCU’s RXD, and the module’s RXD to your MCU’s TXD. Connect the GND pins together.
- Initial Test: Send the command
ATvia a serial monitor at 9600 baud. The module should returnOK
Yes. Most 4G and 5G SIM cards are “downward compatible” and will work with the SIM900A, provided your local carrier still operates a 2G/GSM network
This is almost always a power supply issue. Sending an SMS or connecting to GPRS requires a sudden burst of current (up to 2A). Ensure your power source is rated for at least 5V/2A; a standard computer USB port (500mA) is often insufficient.
Yes. The V4.0 board features audio input and output pins. By connecting a microphone and speaker, you can use AT commands to initiate and receive voice calls
The kit includes the SIM900A V4.0 board and the GSM antenna. You will need a 5V power adapter and a microcontroller (like an Arduino) to begin programming
















