E840-TTL (EC05-xxx) Series 4G CAT1 Module Comprehensive Technical Guide
1. Product Overview
1.1 Introduction
The E840-TTL (EC05-xxx) series is a compact, high-performance 4G CAT1 pin module designed for rapid IoT device integration. Measuring just 25×25 mm, this module enables bidirectional transparent data transmission between serial devices and network servers with minimal configuration. The 2.0mm pin header design simplifies integration into existing IoT projects, supporting both standard industrial voltage ranges and multiple network protocols. With native support for MQTT, HTTP, TCP, and UDP protocols, the module seamlessly connects to major cloud platforms including Alibaba Cloud, OneNET, Baidu Cloud, and Huawei Cloud, making it suitable for a wide range of IoT applications from industrial monitoring to smart city infrastructure.
1.2 Key Features
• 4G CAT1 technology with millisecond-level latency for real-time data transmission
• Multi-region frequency support for global deployment
• Transparent data transmission between serial port and network without protocol conversion
• Dual independent socket connections with master/slave configuration options
• Native MQTT 3.1.1 support for all major IoT cloud platforms
• Automatic Modbus RTU to TCP conversion for industrial automation applications
• Quick AT command support via serial, network, or SMS (modeldependent)
• Configurable heartbeat and registration packets for connection stability
• Multi-link protocol distribution for targeted data routing
• Dual power input support: 4.5~18V DC or 3.3~4.3V lithium battery
• Optional GNSS positioning (GPS/BeiDou/Galileo/GLONASS) on DGC model
• AWS certificate support on DNE-V2 model for enhanced security
• Wide operating temperature range (-40°C to +85°C) for industrial environments
1.3 System Parameters
Category Parameter
Frequency Bands
E840-TTL(EC05-DNC/DGC)
E840-TTL(EC05-DNE)
E840-TTL(EC05-DNE)-V2
Network Protocols
Specification
LTE-TDD: B34/B38/B39/B40/B41
LTE-FDD: B1/B3/B5/B8
LTE-FDD: B1/B3/B5/B7/B8/B20/B28
LTE-FDD: B1/3/5/7/8/20/28
LTE-TDD: B38/40/41
TCP/UDP/MQTT/HTTP/DNS
Positioning Supported Models E840-TTL(EC05-DGC) only Systems GPS/BDS/Galileo/GLONASS joint positioning
Serial Interface Level 3.3V TTL Baud Rate 1200-230400 bps (default: 115200)
Data Bits
Power Supply
8
Stop Bits 1 (default) / 2
Parity
None (default) / Odd / Even RS485 Support Hardware enable pin for external RS485 transceivers
VCC1 Input
VCC2 Input
4.5~18V DC (recommended, 2A @5V minimum load capacity)
3.3~4.3V DC (batterypowered applications, 2.5A @4V minimum load capacity)
Peak Current (VCC1) 2000mA @5V / 1000mA @12V
Standby Current (VCC1) 50mA @5V / 30mA @12V
Physical Dimensions 25×25 mm
Weight 4.5 ± 0.2 g
1.4 Indicator Lights
Indicator Color Status Description
PWR Blue Solid: Power connected
STATE Yellow Off: Searching for SIM card
Flashing: Attaching to network
Solid: Successfully connected to network
DATA Green Flashing: Serial port transmitting/receiving data
LINK Yellow Solid: Successfully connected to server Off: Not connected to server
1.5 Pin Definitions
Pin Number Name Function Description
1, 4, 9, 19 GND Ground Power ground connection
2 VCC1
Input 1 4.5~18V DC input 3
No Connection Leave floating, available for custom I/O in specialized versions
5 SIM_VDD External SIM Power VDD for external SIM card
SIM_CLK External SIM Clock Clock signal for external SIM card
for external SIM card
13 RS485_EN RS485 Enable High during serial transmission, low otherwise, for controlling external RS485 transceivers
14 RELOAD Factory Reset / Upgrade Pull low for 3-5 seconds to restore factory settings; pull low during power-on for firmware upgrade mode
15 STATE STATE Indicator Output For external LED connection (common cathode)
16 LINK LINK Indicator Output For external LED connection (common cathode)
17 DATA DATA Indicator Output For external LED connection (common cathode)
18 VCC2 Power Input 2 3.3~4.3V DC input for batterypowered applications
20 ANT-GNSS GNSS Antenna 1st generation IPEX connector for GNSS antenna (DGC model only)
26 ANT-4G 4G Antenna 1st generation IPEX connector for 4G LTE antenna