SIM800C vs A7670C vs SIM7600: Which GSM/4G Module Should You Choose?
Choosing the right cellular communication module is one of the most important decisions in any IoT project. Whether you are building a remote data logger, an SMS-based alert system, or a GPS tracking device, the module you pick determines your network reach, power budget, data throughput, and long-term viability. In India's rapidly evolving telecom landscape — where 2G networks face an uncertain future while 4G coverage expands aggressively — making an informed choice is more critical than ever.
In this guide we compare four of the most popular modules available at Wirelays: the SIM800C, A7670C, A7672S, and SIM7600. By the end you will know exactly which module fits your project requirements and budget.
SIM800C — The Budget 2G Workhorse
The SIM800C from SIMCom is a quad-band GSM/GPRS module that has been a staple of the Indian maker and industrial community for years. It operates on the 850/900/1800/1900 MHz bands and communicates over a simple TTL-level UART serial interface, making it extremely easy to integrate with Arduino, ESP32, and other microcontrollers.
Key Specifications
- Network: 2G GSM/GPRS
- Data Speed: Up to 85.6 kbps (GPRS Class 12)
- Interface: UART (TTL), AT commands
- Supply Voltage: 3.4 V – 4.4 V (typ. 4.0 V)
- Peak Current: ~2 A during transmission bursts
- Price Range: Approximately ₹200 – ₹400
- GPS: Not built-in
Best For
SMS alerts, voice calls, basic GPRS data transfer, and cost-sensitive prototypes. The SIM800C remains unbeatable on price. However, keep in mind that Indian telecom operators are gradually phasing out 2G, so new long-term deployments should consider 4G alternatives.
A7670C — The 4G Cat-1 Sweet Spot
The A7670C from SIMCom is a 4G LTE Cat-1 module designed as a modern replacement for 2G modules. It supports LTE-FDD and LTE-TDD bands relevant to Indian operators, with 2G GSM fallback for areas where 4G has not yet been rolled out.
Key Specifications
- Network: 4G LTE Cat-1 with 2G fallback
- Data Speed: Up to 10 Mbps downlink / 5 Mbps uplink
- Interface: UART, USB, AT commands (largely compatible with SIM800 AT set)
- Supply Voltage: 3.4 V – 4.2 V
- VoLTE: Supported
- Price Range: Approximately ₹600 – ₹900
- GPS: Not built-in (external GNSS option available)
Best For
IoT data logging, cloud-connected sensors, MQTT/HTTP communication, and any project that needs reliable 4G connectivity at moderate cost. The AT command compatibility with SIM800 makes migration straightforward.
A7672S — A Close Sibling of A7670C
The A7672S is another Cat-1 module from SIMCom in the same family as the A7670C. It shares the same form factor and most features but differs slightly in supported LTE bands. In practice, for Indian deployments (Jio, Airtel, Vi bands), both modules perform comparably.
Key Differences from A7670C
- Slightly different LTE band configuration — check your operator's band requirements
- Same AT command set and physical footprint
- Pricing and power consumption are virtually identical
Choose the A7672S if the specific band combination better matches your target operator, otherwise the A7670C is the default recommendation.
SIM7600 — High-Speed 4G with Built-in GPS
The SIM7600 series (SIM7600CE, SIM7600EI) is a 4G LTE Cat-4 module offering significantly higher data rates and an integrated GNSS (GPS + GLONASS + BeiDou) receiver. It is the go-to choice when your project demands both fast data and location tracking.
Key Specifications
- Network: 4G LTE Cat-4
- Data Speed: Up to 150 Mbps downlink / 50 Mbps uplink
- Interface: UART, USB, AT commands
- Supply Voltage: 3.4 V – 4.2 V
- Peak Current: ~2 A
- Price Range: Approximately ₹2,500 – ₹4,000
- GPS: Built-in GNSS (GPS, GLONASS, BeiDou)
Best For
Vehicle tracking, high-bandwidth data applications, firmware OTA updates, video streaming, and any project that needs simultaneous cellular data and GPS without adding extra hardware.
Comparison Table
| Feature | SIM800C | A7670C | A7672S | SIM7600 |
|---|---|---|---|---|
| Network | 2G GSM/GPRS | 4G Cat-1 + 2G | 4G Cat-1 + 2G | 4G Cat-4 |
| Max Download Speed | 85.6 kbps | 10 Mbps | 10 Mbps | 150 Mbps |
| Power Consumption | Low | Low-Medium | Low-Medium | Medium-High |
| Approx. Price (INR) | ₹200 – ₹400 | ₹600 – ₹900 | ₹600 – ₹900 | ₹2,500 – ₹4,000 |
| Built-in GPS | No | No | No | Yes |
| VoLTE | No | Yes | Yes | Yes |
| Best Use Case | SMS alerts, basic data | IoT data logging, MQTT | IoT data logging, MQTT | Tracking, high-speed data |
| Future-Proof | Low (2G sunset risk) | High | High | High |
Which Module Should You Choose?
Scenario 1: Basic SMS Alerts or Voice Call Triggers
If your project simply needs to send an SMS when a sensor triggers, or accept an incoming call to toggle a relay, the SIM800C is the cheapest and simplest option. Just be aware of the 2G sunset timeline in your region.
Scenario 2: IoT Data Logging and Cloud Communication
For sending sensor data to platforms like ThingSpeak, Blynk, AWS IoT, or your own server over MQTT or HTTP, the A7670C offers the best balance of cost, speed, and future-proofing. Its AT command compatibility with SIM800 also means you can reuse much of your existing code.
Scenario 3: Vehicle or Asset Tracking
When you need real-time GPS coordinates along with cellular data (for fleet management, bike tracking, or asset monitoring), the SIM7600 is the clear winner. Its integrated GNSS eliminates the need for a separate GPS module, simplifying your PCB design and BOM.
Scenario 4: Maximum Cost Savings with 4G
If budget is tight but you still want 4G reliability, compare the A7670C and A7672S based on the LTE bands supported by your SIM operator. Both are priced similarly and offer excellent value.
Getting Started
All four modules are available at Wirelays with breakout boards, development kits, and antennas to help you prototype quickly. Browse our full range of communication modules or check out our IoT modules collection to find the right fit.
Need help choosing? Contact our team — we are happy to recommend the right module for your specific application.