The SIM800L is a compact GSM/GPRS module designed for cellular communication in embedded and IoT applications. It supports SMS, voice calls, and GPRS data over 2G networks, making it suitable for tracking systems, remote monitoring, alerts, and basic internet-enabled projects. Its small form factor and AT-command control allow easy integration with microcontrollers.
Core Module Specifications
• Cellular Standard: GSM / GPRS (2G)
• Frequency Bands: Quad-band 850 / 900 / 1800 / 1900 MHz
• Data Services: GPRS Class 12
• Control Method: AT commands
• SIM Type: Micro SIM
Electrical & Interface
• Operating Voltage: 3.4 V – 4.4 V (typical 4.0 V)
• Logic Level: 2.8 V (UART)
• Communication Interface: UART (TX, RX)
• Current Consumption:
– Idle: ~20 mA
– Peak (TX burst): up to 2 A
• Audio Interface: Mic and speaker pins available


Performance Characteristics
• SMS: Text and PDU modes supported
• Voice Calls: Full duplex
• Internet: TCP/IP stack via GPRS
• Network Registration: Automatic
• Response Time: Fast network attach (signal dependent)
Physical Characteristics
• Module Type: GSM/GPRS cellular module
• Form Factor: Ultra-compact PCB
• Antenna Interface: External GSM antenna pad / IPEX (variant dependent)
• Lightweight and space-efficient design
Compatibility
• Arduino Uno / Nano / Mega (with level shifting)
• ESP8266 / ESP32
• STM32, AVR, PIC microcontrollers
• Raspberry Pi (UART interface)
Key Advantages
• Small size with full GSM functionality
• Supports SMS, calls, and data
• Widely supported AT command set
• Ideal for low-cost cellular projects
Technical Insights
• Requires a stable power supply capable of high peak current
• External antenna strongly recommended for reliable operation
• Level shifting needed for 5 V UART controllers
• Proper grounding improves RF performance
Applications
• GPS trackers
• SMS alert systems
• Remote data monitoring
• IoT gateways
• Home and industrial automation
Pro Tip
• Use a Li-ion battery or high-current DC-DC converter
• Add large bulk capacitors (470 µF–1000 µF) near VCC
• Ensure good antenna placement for stable signal
• Disable unused features to reduce power usage
Package Includes
• 1 × SIM800L GPRS GSM Module
