1. Prodotto finitoview
The Quectel LG77L (part of the BG77xA-GL series) is a high-performance, ultra-compact LPWA (Low-Power Wide-Area) module designed for IoT applications. This module integrates a GNSS engine and supports multiple satellite navigation systems including GPS, GLONASS, Galileo, BDS, and QZSS, along with anti-jamming capabilities. It is fully compliant with the 3GPP Rel-14 specification, supporting LTE Cat M1 and LTE Cat NB1/NB2 bands for global carrier compatibility.
Featuring a MIPS 5150 processor, the LG77L module is engineered for ultra-low power consumption, utilizing integrated RAM and flash to achieve minimal current draw in various standby and hibernation modes (3GPP PSM and e-I-DRX). Its advanced LGA package facilitates fully automated manufacturing, making it suitable for high-volume production environments.
The module also incorporates a comprehensive hardware-based security feature, Integrated Security Elements (ISE), ensuring robust data protection. With a rich set of Internet protocols and industry-standard interfaces, the LG77L is ideal for a wide range of IoT applications such as wireless POS terminals, smart metering, asset tracking, and wearable devices.

2. Caratteristiche principali
- Integrated RAM and flash for efficient operation.
- Embedded with abundant Internet service protocols.
- Support for QuecLocator® and DFOTA (Delta Firmware Over-The-Air) for location services and remote updates.
- Rich set of external, multi-band interfaces for convenient application integration.
- Fast time-to-market with reference designs, evaluation tools, and technical support.
- Robust mounting and interfaces for reliable performance.
- Comprehensive hardware-based security with Integrated Security Elements (ISE).
3. Specifiche
The following table details the key specifications for the Quectel LG77L (BG77xA-GL Series) module. For complete and up-to-date specifications, please refer to the official Quectel datasheet.

| Caratteristica | Descrizione |
|---|---|
| Prodotto | BG77xA-GL Series |
| Fattore di forma | LGA |
| Dimensioni (mm) | Dimensioni: 14.9 × 12.9 × 1.9 |
| EUT | LTE Cat M1/Cat NB2 |
| Bande di frequenza (MHz) | LTE-FDD: B1/B2/B3/B4/B5/B8/B12/B13/B18/B19/B20/B25/B26/B27/B28/B66/B71/B85; LTE-TDD: B39/B40/B41 (for Cat M1 only) |
| Weight (approx. g) | 1.25 |
| Temperatura di esercizio | Temperatura di esercizio -30°C ~ +75°C |
| Temperatura estesa | Temperatura di esercizio -40°C ~ +85°C |
| LTE Cat M1 Data Rate (Kbps) | Massimo 588 (DL), Massimo 1119 (UL) |
| LTE Cat NB1 Data Rate (Kbps) | Massimo 32 (DL), Massimo 10 (UL) |
| LTE Cat NB2 Data Rate (Kbps) | Massimo 127 (DL), Massimo 158.5 (UL) |
| GNSS Data Rate (Kbps) | Massimo 157 (DL), Massimo 89.6 (UL) |
| Protocolli | Point-to-point MO and ME, 3GPP Broadcast, Text and PDU mode |
| sms | PDU/TEXT mode |
| Interfacce UART | 1 (MAIN, DEBUG, NMEA) |
| Interfacce USB | 1 (USB 2.0) |
| I2C | 1 |
| ADC | 2 |
| GPIO | 5 |
| RESET | 1 |
| PCM | 1 |
| Interfacce antenna | 2 (for Main Antenna and GNSS Antenna, respectively) |
| OpenCPU | Simplifies the development of Embedded Applications |
| GNSS | SÌ |
| DFOTA | SÌ |
| USB Serial Driver | Android 4.x/5.x/6.x/7.x/8.x/9.x/10.x/11.x/12.x |
| RIL Driver | Android 4.x/5.x/6.x/7.x/8.x/9.x/10.x/11.x/12.x |
| Selezione SIM | SÌ |
| VoLTE | Opzionale |
| SIM elettronica | SÌ |
| Aggiornamento del firmware | Via USB interface |
| Volume di fornituratage Gamma | 2.2V-4.3V (typ. 3.8V) |
| Consumo energetico | 4.2 µA (PSM) |
| Potenza massima in uscita | Power Class 5 (23dBm) for LTE Bands |
| Certificazioni | Vodafone/Deutsche Telekom/Telstra/Verizon/AT&T/T-Mobile/GCF/PTCRB/FCC/IC/CE/RCM/JATE/TELEC/KC/NCC/Anatel/CCC/SRRC/RoHS/WEEE |
4. Configurazione e integrazione
The Quectel LG77L is an SMT (Surface Mount Technology) module designed for integration into larger electronic systems. It features an LGA (Land Grid Array) package, which requires professional soldering and assembly processes.
4.1. Hardware Integration
- Montaggio: The module should be mounted onto a host PCB using standard SMT reflow soldering techniques. Ensure proper alignment and temperature profiles to prevent damage.
- Alimentazione elettrica: Provide a stable power supply within the specified range of 2.2V to 4.3V (typical 3.8V). Pay close attention to power supply filtering and decoupling to ensure stable operation.
- Collegamenti dell'antenna: The module requires two antennas: a Main Antenna for LTE communication and a dedicated GNSS Antenna for satellite reception. Ensure these are correctly connected to the respective pads on the module and are suitable for the operating frequencies.
- Interfacce: Connect the module to your host system via the available interfaces: UART (MAIN, DEBUG, NMEA), USB 2.0, I2C, GPIOs, and PCM as required by your application.
4.2. Integrazione software
- Autisti: Install necessary USB serial drivers and RIL drivers for Android operating systems (Android 4.x through 12.x) if integrating with an Android device.
- Comunicazione: The module typically communicates with the host system using AT commands. Refer to the Quectel AT Command Manual for detailed command sets for cellular and GNSS functions.
- OpenCPU: For advanced users, the OpenCPU feature simplifies embedded application development directly on the module.
5. Istruzioni per l'uso
Once integrated and powered, the LG77L module operates by receiving and transmitting data over LTE networks and acquiring positioning data from GNSS satellites.
5.1. GNSS Operation
- Acquisizione satellitare: Ensure the GNSS antenna has a clear, unobstructed view del cielo per una ricezione ottimale del segnale satellitare.
- Dati in uscita: GNSS data (e.g., NMEA sentences) can be accessed via the UART or USB interfaces. Configure the module using AT commands to enable and format the desired output.
- Sistemi supportati: The module supports GPS, GLONASS, Galileo, BDS, and QZSS constellations for enhanced accuracy and availability.
5.2. LTE Communication
- Registrazione di rete: The module will attempt to register with an available LTE Cat M1 or NB1/NB2 network upon power-up. Ensure a valid SIM card is inserted if required by your application.
- Trasmissione dati: Use AT commands to establish data connections, send/receive data, and manage network services. The module supports various Internet protocols.
- Modalità a basso consumo: To conserve power, the module can be configured to enter PSM (Power Saving Mode) or e-I-DRX (extended Discontinuous Reception) modes. Refer to the Quectel power management guide for implementation details.
6. Manutenzione
As an embedded module, the LG77L requires minimal user maintenance. However, certain practices ensure its longevity and optimal performance.
- Aggiornamenti del firmware: The module supports DFOTA (Delta Firmware Over-The-Air) and firmware updates via the USB interface. Regularly check Quectel's website for the latest firmware versions to benefit from performance improvements and bug fixes.
- Condizioni ambientali: Operate the module within the specified temperature range (-30°C to +75°C, extended -40°C to +85°C). Avoid exposure to excessive moisture, dust, and corrosive environments.
- Ispezione fisica: Periodically inspect the module and its connections for any signs of physical damage or corrosion, especially in harsh environments.
7. Risoluzione Dei Problemi
If you encounter issues with your LG77L module, consider the following troubleshooting steps:
- Nessun potere: Verify that the power supply is connected correctly and provides the specified voltage (2.2V-4.3V). Check for any short circuits or incorrect polarity.
- Nessuna registrazione di rete:
- Ensure the Main Antenna is properly connected and functional.
- Verify that a valid and activated SIM card is inserted (if applicable).
- Controlla la copertura di rete nella tua zona.
- Confirm the module's firmware is up to date.
- No GNSS Fix / Poor Accuracy:
- Ensure the GNSS Antenna has a clear, unobstructed view del cielo.
- Verify the GNSS Antenna is correctly connected.
- Check for potential sources of interference (e.g., nearby electronics, metal objects).
- Confirm GNSS functionality is enabled via AT commands.
- Communication Errors (UART/USB):
- Verify correct wiring and pin assignments for the interface.
- Check baud rates and other serial port settings.
- Ensure the correct drivers are installed on the host system.
- Use AT commands to check the module's internal status and diagnostics.
- Surriscaldamento del modulo: Ensure adequate ventilation and heat dissipation, especially if the module is operating at its maximum temperature range or under heavy load.
For more detailed troubleshooting, consult the Quectel LG77L Hardware Design Guide and AT Command Manual.
8. Suggerimenti per l'utente
- Optimal GNSS Performance: For the best possible GNSS signal reception and positioning accuracy, always ensure the GNSS antenna has a clear, unobstructed view of the sky. Avoid placing the antenna near large metal objects or other electronic components that could cause interference.
- Gestione energetica: To maximize battery life in portable applications, carefully implement the module's low-power modes (PSM and e-I-DRX). Proper configuration can significantly reduce power consumption when the module is idle.
- Documentazione: Always refer to the latest official Quectel documentation, including the Hardware Design Guide, AT Command Manual, and application notes, for detailed integration instructions, software development, and advanced features.
- Selezione dell'antenna: Choose high-quality, appropriate antennas for both LTE and GNSS to ensure reliable communication and accurate positioning. Antenna placement and impedance matching are critical for performance.
9. Garanzia e supporto
Warranty information for the Quectel LG77L module is typically provided by the seller or directly by Quectel. Please retain your proof of purchase for warranty claims.
9.1. Supporto tecnico
For technical assistance, detailed documentation, or specific inquiries regarding the LG77L module, please contact:
- Your point of purchase or distributor.
- Quectel Wireless Solutions official support channels.
When contacting support, please be prepared to provide the module's model number (LG77L or BG77xA-GL), any relevant firmware versions, and a detailed description of the issue you are experiencing.





