1. Introduction
This manual provides detailed instructions for the setup, operation, and troubleshooting of the SIMCOM A7672E-LASE Core Board Development Kit. This kit is designed for developers working with 2G, 4G LTE CAT1 modules, offering a compact and functional solution for various applications.
Please note: This product is a module Core board and only includes the module. It does not include a SIM phone card.
2. Safety Information
- WARNING: Keep out of reach of children.
- Ensure proper handling of electronic components to prevent electrostatic discharge.
- Do not expose the board to moisture or extreme temperatures outside its operating range.
- Always ensure correct voltage supply to avoid damage to the module. Refer to the "Power Supply" section for details.
3. Product Overview
3.1. Components
The SIMCOM A7672E-LASE Core Board Development Kit typically includes:
- SIMCOM A7672E-LASE Core Board
- FPC Antenna
3.2. Features
- Compact 24x24 size function board, facilitating design of compact and fully functional terminal products.
- Integrated multi-constellation GNSS receivers supporting GPS, GLONASS, BeiDou, Galileo, and QZSS for accurate positioning.
- Compatible with various NB/CAT-M (SIM7000, SIM7070) and GSM/GPRS (SIM800A, SIM800F) modules.
- Supports LTE series modules including SIM7000G/A/E, SIM7070E/G, A7670C/E/SA/G, A7672G/E/SA, SIM7670/SIM7672.
- Supports TTL & USB 2.0 interfaces.
- Network protocols: TCP/IP/IPV4/IPV6/Multi-PDP/FTP/FTPS/HTTP/HTTPS/DNS/RNDIS/ECM/PPP.
- Applicable regions: China/India, Central Africa, Asia Pacific, North America/United States Verizon, Europe, Mexico, Japan, Latin America, Australia, New Zealand, South Korea.
3.3. Specifications
| Project | Description |
|---|---|
| Product Name | 4G Cat1 Core Board |
| Model | DD-MCore-A7672E-LASE |
| Package | 23PIN (2.54mm) |
| Power Supply (VIN) | 5-16V DC (recommended 5V 2A) |
| Power Supply (VBAT) | 3.3V-4.3V (typical 3.8V, for lithium battery) |
| UART | 3.3V TTL (Default) |
| SIM Card | Nano SIM |
| LED Indicators | Power/Network light |
| USB Interface | Yes (USB 2.0) |
| Size (mm) | 44.45*31.75*12.44 (Including pin height) |
| Operating Temperature | -40℃ to 85℃ |
| Network Band | LTE-FDD: B1/B2/B3/B4/B5/B7/B8/B28/B66, GSM/GPRS/EDGE: 900/1800 MHz |
| Network Speed | LTE: 10Mbps (DL), 5Mbps (UL) |
| Network Protocol | TCP/IP/IPV4/IPV6/MultiPDP/FTP/FTPS/HTTP/HTTPS/DNS/RNDIS/ECM/PPP |
| Function | LTE CAT1 + 4G + 2G + Voice |
| Type | Core Board |
| Origin | Mainland China |
| Condition | New |
Note: The module suffix (e.g., -LASE) indicates the applicable region. For Europe/Middle East/Africa, the 'E' suffix is relevant.
4. Setup and Installation
4.1. Pin Description (P1)
| Pin Number | Name | Pin Description | Remark |
|---|---|---|---|
| 1 | SC | USIM1 Bus clock output | When the SIM card is external, the external SIM card holder can be directly connected to the SC, SD, SR, SV pins. |
| 2 | SD | USIM1 Bus data | |
| 3 | SR | USIM1 Bus reset output | Note: The onboard card holder and the external card holder cannot be inserted at the same time. |
| 4 | SV | USIM1 card power supply output, output voltage can be changed dynamically according to the external card type, output current maximum 50mA | |
| 5 | STA | Power-on status indication: when the core board is powered on and initialization is complete, STA outputs a high level, otherwise it maintains a low level | Used to determine whether the core board is powered on. Voltage domain: 3.3V |
| 6 | TXD | Main serial port sending, used for AT command configuration and data transmission | Voltage domain: 3.3V; other levels can be changed by enabling VTTL |
| 7 | RXD | Main serial port receiving, used for AT command configuration and data transmission | |
| 8 | RTS | Hardware flow control, main serial port RTS input. | Voltage domain 3.3V |
| 9 | PEN | The core board power enable pin is pulled up to VIN by default. It will automatically start when powered on. When pulled down, the core board power supply has no output. If not used, leave it unconnected. | |
| 10 | P/R | Module power on/off/reset control, default is PWK pin | |
| 11 | GND | Negative power input | |
| 12 | P/G | Default is GND |
4.2. Pin Description (P2)
| Pin Number | Name | Illustrate | Remark |
|---|---|---|---|
| 13 | VEXT | Internal 1.8V power output, maximum output current 50mA, cannot power high power loads | Electrostatically sensitive, no need to be suspended |
| 14 | VTTL | External reference level input for level conversion circuit, invalid by default | |
| 15 | CTS | Hardware flow control, main serial port CTS output | Voltage domain 3.3V |
| 16 | RI | Ringing indication, when receiving URC report, it outputs low level for 60ms, and then returns to high level state | Voltage domain 3.3V |
| 17 | DTR | Sleep wake-up: when the core board enters sleep mode, pull down DTR to wake up the core board | Voltage domain 3.3V |
| 18 | TXD2 | Serial port 2 sends, not used by AT firmware, just leave it floating | Voltage domain 3.3V |
| 19 | RXD2 | Serial port 2 receiving, not used by AT firmware, just leave it unconnected | Voltage domain 3.3V |
| 20 | VBAT | Module power input, supports 3.4~4.2V input, typical value 3.8V, can be used for lithium battery power supply; when using VIN power supply, VBAT output 3.8V | PEN pin is disabled when powered by VBAT |
| 21 | NET | Network status indication | |
| 22 | VIN | Power input positive, supports 5-16V DC input | You can connect one or both. |
| 23 | VIN | ||
| 24 | TXD | Send through the main serial port, which is convenient for monitoring the data interaction between the main control and the core board after the core board is installed | To assist in testing |
| 25 | RXD | Main serial port receiving, convenient for monitoring the data interaction between the main control and the core board after the core board is installed | |
| 26 | GND | Main serial port auxiliary test common ground pin | |
| 27 | VB | USB_VBUS, VBUS presence detection input | USB XH2.0 Terminal Blocks |
| 28 | UN | USB_N, USB bus differential negative | |
| 29 | UP | USB_P, USB bus differential positive | |
| 30 | GND | GND, ground |
Note: For conventional applications, only VIN, GND, TXD, RXD, and PEN are needed. Other pins can be left floating.
Note: VBAT and VIN cannot be used as power input at the same time. When VBAT is used to power the core board, the PEN pin becomes invalid.
4.3. Power Supply
The core board supports three power supply modes: VIN, VBAT, and USB.
- VIN: Power supply range is 5V~16V. The power needs to be more than 8W, and the recommended power supply is 5V 2A.
- VBAT: Power supply range is 3.3V~4.3V, generally used for lithium battery power supply.
- USB: Powered by 5V USB data cable. Some computer USB interfaces (especially older USB 2.0 ports) may have insufficient driving capacity, leading to frequent restarts. It is recommended to connect to computer USB 3.0 or use an independent power supply if issues occur.
Important Note:
- VIN and VBAT cannot power the core board at the same time.
- The actual input voltage must be within the minimum and maximum value range.
4.4. Power On/Off Control
The core board automatically powers on by default. For applications requiring controlled power management or handling abnormal situations, it is recommended to use the PWK and PEN pins.
4.4.1. PWK Pin (Power Key)
Power On: The core board automatically powers on by default. The power on sequence is shown in the diagram below.
Shutdown: In the power-on state, pull the PWK pin low for more than 50ms and then pull it high for at least 650ms to enter the shutdown procedure. Maintain the PWK pin low for more than 2 seconds to ensure the shutdown procedure is fully executed. After execution, the core board will remain in the shutdown state if the low level is maintained.
Special Note: This product defaults to automatic boot. We only provide the POW-RKEY boot solution. This is not considered a product defect for returns.
For hardware developers, please remove the material with bit number R3 and C5 on the PWK/RST pin after receiving the goods, or short 3.3V on PWK/RST pin.
4.4.2. PEN Pin (Power Enable)
By default, PEN is internally pulled up to VIN, meaning the core board is enabled and powered on. If the PWK pin fails to shut down, you can control PEN to directly cut off the power supply. Pulling down the PEN pin disconnects the power supply of the core board to achieve power off and shutdown.
Note: When using an MCU's GPIO to control the PEN pin, it is recommended to add a transistor driver.
4.5. Serial Port (TTL) Interface
The core board has two serial ports. Serial port 1 is the main serial port for AT command interaction and data transmission. Serial port 2 has no function in AT firmware and can be left floating.
- Supported Baud Rates: 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800bps.
- Wiring: When communicating with a master control (e.g., MCU), TXD and RXD pins are cross-wired (MCU TXD to Core Board RXD, MCU RXD to Core Board TXD).
- Default Level: The default serial port level is 3.3V TTL. If your master control serial port level is not 3.3V, level matching is required. You can modify the jumper resistor on the core board and connect the VTTL pin to the target voltage.
| IO Level Value | Modification Description | Remark |
|---|---|---|
| 3.3V | Solder RT1, do not solder RT2 | Default factory welding method |
| Other Voltages | Solder RT2, do not solder RT1, VTTL connected to target voltage | Requires self-modification or contact sales |
Note: After modifying the IO level, the levels of the TXD, RXD, TXD2, RXD2, DTR, RI, CTS, RTS, and STA pins will all become VTTL.
4.6. USB Interface
The USB interface can be used for data transmission and communication. A USB driver needs to be installed for proper communication.
Important Note:
- The USB cable must have data transmission functionality.
- If the driver is not installed successfully after connecting the core board to the computer via USB, open the computer's Device Manager. You may see three devices with yellow exclamation marks under "Other Devices". You can update the drivers sequentially.
5. Operation
5.1. DTR Wake-up
The DTR pin is the sleep mode trigger pin. Leaving it floating when not in use is acceptable. Entering sleep mode significantly reduces standby power consumption. In sleep mode, the main serial port function is turned off.
To enable sleep mode, use the AT+CSCLK=1 command. Ensure DTR is kept at a high level (default internal pull-up is high). The module can be woken up by pulling DTR low by the host (it needs to be kept low in sleep mode to keep the core board awake).
5.2. PC-side Testing Method (Serial Port Debugging)
This section outlines the steps for connecting the core board to a computer for serial port debugging using AT commands.
Video 1: Demonstration of wiring the core board and performing serial port debugging.
- Connect Hardware:
- Connect the FPC antenna to the core board.
- Insert a Nano SIM card into the SIM slot.
- Connect the core board's serial port (TXD, RXD, GND) to a TTL-to-USB converter. Ensure cross-wiring (Core Board TXD to Converter RXD, Core Board RXD to Converter TXD).
- Connect the USB port of the TTL-to-USB converter to your computer.
- Check Device Manager:
- Open Device Manager on your computer.
- Verify that the serial port (COM port) for the TTL-to-USB converter is recognized. If drivers are missing, install them.
- Open Serial Port Tool:
- Use a serial port debugging tool (e.g., AT Terminal V1.6.6 as shown in the video).
- Configure the tool with the correct COM port and baud rate (e.g., 115200).
- Perform AT Commands Test:
- After power on, the core board power indicator (red light) should be on. Wait for about 10 seconds for the network indicator (blue light) to start flashing. This indicates the core board is on and ready for AT commands.
- Enter the corresponding AT commands to test functionality.
5.2.1. AT Command Examples and Responses
| Step | State | AT Commands and Return Values | Illustration |
|---|---|---|---|
| 1 | Send | AT | Handshake test. |
| Return | OK | If "OK" is returned, it means the serial communication is normal. | |
| 2 | Send | AT+CPIN? | Check SIM card status. |
| Return | +CPIN: READY OK | If "READY" is returned, it means the card reading is successful. If ERROR is returned, the card reading fails. | |
| 3 | Send | AT+CSQ | Query the RF signal quality. |
| Return | +CSQ: 24,99 OK | Parameter 1: Signal quality (0~31), make sure the signal quality is greater than 18, otherwise data communication may be unstable. 0: -113dBm or less 1: -111dBm 2..30: -109dBm... -53dBm 31: -51dBm or higher 99: Unknown or undetectable Parameter 2: Not enabled, can be ignored. | |
| 4 | Send | AT+CEREG? | Query network registration status. |
| Return | +CEREG: 0, 1 OK | Parameter 1: Controls unsolicited result codes, 0 is disabled. Parameter 2: Registration status, 1 indicates successful registration. 0: Unregistered, the module has not currently searched for a new operator to register 1: Successfully registered 2: Unregistered, but the module is searching for a new operator to register 3: Registration denied 4: Unknown 5: Registered, roaming |
6. Maintenance
The SIMCOM A7672E-LASE Core Board is a robust electronic component designed for long-term operation. Regular maintenance is generally not required under normal operating conditions.
- Keep the board clean and free from dust and debris.
- Avoid exposing the board to static electricity.
- Ensure proper ventilation if the module is enclosed in a casing to prevent overheating.
- Periodically check power connections for secure fit and proper voltage.
7. Troubleshooting
7.1. Common Issues and Solutions
- Module not powering on or restarting frequently:
- Check the power supply. Ensure it meets the specifications (VIN: 5-16V DC, recommended 5V 2A; VBAT: 3.3-4.3V).
- If using USB for power, ensure the USB port provides sufficient current (some older USB 2.0 ports may be insufficient). Consider using a USB 3.0 port or an independent power supply.
- Ensure VIN and VBAT are not used simultaneously for power input.
- Serial port communication issues:
- Verify correct wiring between the core board and the TTL-to-USB converter (TXD to RXD, RXD to TXD).
- Check if the USB driver for the TTL-to-USB converter is correctly installed in Device Manager.
- Ensure the serial port tool is configured with the correct COM port and baud rate.
- If the serial port level is not 3.3V TTL, ensure proper level matching is implemented.
- SIM card not detected or network registration failure:
- Ensure the Nano SIM card is correctly inserted.
- Use the
AT+CPIN?command to check SIM card status. If it returns "ERROR", the card reading failed. - Use the
AT+CSQcommand to check RF signal quality. A value greater than 18 is recommended for stable data communication. - Use the
AT+CEREG?command to check network registration status.
- Module not shutting down via PWK pin:
- Ensure the PWK pin is pulled low for more than 50ms and then high for at least 650ms.
- If PWK fails, use the PEN pin by pulling it low to disconnect power. Note that frequent use of PEN for shutdown is not recommended as it may damage the file system.
8. User Tips
- For customized product requirements, contact the seller with detailed specifications to discuss feasibility with their engineers.
- If you need to order in bulk or find shipping costs unexpectedly high, contact the seller to check for exact stock and potential shipping cost reductions.
- When debugging, ensure the core board's GND, power supply GND, and USB to TTL converter's GND are all connected together ("common ground").
9. Warranty and Support
For technical support, inquiries, or assistance with the SIMCOM A7672E-LASE Core Board, please contact the manufacturer or seller directly.
Manufacturer: Hunan Sanai Electronic Technology Co., Ltd
- Address: Building C3, Yupingshan International Industrial City, Xieyuan Road, Ningxiang Economic and Technological Development Zone, Changsha City, Hunan Province
- Email: pur1@muz-tech.com
- Telephone: 86-18188996558
EU Authorized Representative: EUREP ENV S.L.
- Address: ES-AVDA INDUSTRIA, NUM 16, ESC. A, PUERTA 207, 28760 TRES CANTOS - (MADRID)
- Email: eurep@eurep-gmbh.de
- Telephone: 34-67870708
For the full user manual in PDF format, please refer to the official document: SIMCOM A7672E-LASE User Manual (PDF).
10. Compliance Information
The product described in this manual conforms to relevant Union legislation:
- Electromagnetic Compatibility (EMC) Directive: 2014/30/EU
- Restriction of the Use of Certain Hazardous Substances (RoHS) Directive: 2011/65/EU
The following harmonized standards and technical specifications have been applied:
CE UKCA FC
Note: Specific compliance logos were not provided in the allowed image URLs. The text marks above indicate conformity.