LTE IoT 6 Click is a compact add-on board that contains an IoT module with worldwide coverage. This board features the SARA-R412M, a cellular module that offers multi-band data transmissions for Low Power Wide Area solutions in a compact form factor from u-Blox. It provides software-based multi-band configurability enabling international multi-regional coverage in LTE Cat M1/NB1 and (E)GPRS radio access technologies. It also ensures data integrity between applications via secure communication protocols (two-way authentication between the client and server) and provides critical firmware updates thanks to the u-Blox proprietary uFOTA (firmware over the air). This Click board™ is suitable for secure low-power IoT applications requiring deeper range (underground) and extended battery life.

LTE IoT 6 Click is supported by a mikroSDK compliant library, which includes functions that simplify software development.

LTE IoT 6 Click is based on the SARA-R412M, an ultra-compact LTE Cat M1/NB1, and EGPRS module with multi-regional coverage with data communications up to 1200 kbit/s from u-Blox. It ensures data integrity between applications via secure communication protocols, notably including two-way authentication between the client and server, a strategy often utilized with cloud services. Thanks to the u-Blox nested design principle, SARA modules are compatible with other u-Blox product families, enabling easy migration from 2G, 3G, and 4G. The SARA-R412M module target long life, low-maintenance, cost-sensitive, lower power consumption, extended battery life applications, and are ideal for mission-critical IoT solutions, as they include a unique and immutable root-of-trust.

This module requires a power supply of 3.8V. Therefore, the Click board™ incorporates an low-dropout(LDO) regulator, labeled as TPS7A7002 by Texas Instruments. This IC can output up to 3A of current, still maintaining an excellent regulation. Its task is to provide a stable 3.8V power supply, capable of mitigating voltage drops at the input when a high current peak appears (typically at the StartUp of the device).

The SARA-R412M communicates with MCU using the UART interface with commonly used UART RX and TX pins with the hardware flow control pins UART CTS, RTS, RI (Clear to Send, Ready to Send, and Ring Indicator). It supports automatic baud rate detection, operates at 115200 bps by default configuration, and is used for data transmission and exchanging AT commands with the host MCU. This Click board™ is also USB 2.0 compliant, equipped with the USB type C connector with a maximum 480 Mbit/s data rate available for the diagnostic purpose only. The module itself acts as a USB device and can be connected to any USB host equipped with compatible drivers.

The onboard push-button labeled as PWR routed to the AN pin on the mikroBUS™ socket represents the Ignition (Power-On) button whose function can be visually displayed by the yellow LED labeled as STAT used to indicate the Operational Status of the device. If the device is already powered up, a LOW pulse with a duration of 1.5s on this pin will power the module down. It is also possible to power down the module by issuing the AT+CPWROFF command or with a Reset function routed to the RST pin on the mikroBUS™ socket that will cause an abrupt Power-Down (forced Power-Down) by sending an active low input on this pin with the duration of 10s. In addition to the STAT LED, this Click board™ has an additional LED indicator, a red LED labeled as TX used to indicate the Network Status.

LTE IoT 6 Click has on itself the SMA antenna connector with an impedance of 50Ω, and it can be used for connecting the appropriate antenna. Besides the LTE SMA connector, this Click board™ also has a nano-SIM card slot that provides multiple connections and interface options. The unpopulated header labeled as J1 allows you to access the configurable GPIO and EXT Interrupt pin of the SARA module, while test points marked from TP1 to TP6 allow you easy FW upgrades and testing of the module.

Customers can future-proof their solutions through over-the-air firmware updates, thanks to the uFOTA client/server solution that utilizes LWM2M, a light and compact protocol ideal for IoT. We have also provided accessible test points directly connected to the TxD and RxD pins for FW upgrade purposes.

This Click board™ can be interfaced with both 3.3V and 5V MCUs, which can be set via jumper labeled as VCC SEL because a proper logic voltage level conversion is performed by appropriate voltage level shifters, while the onboard LDOs ensures that the module is powered by recommended voltage levels.

• Interface: GPIO, UART
• Compatibility: mikroBUS™
• Dimensions: 57.15 x 25.4mm
• Input Voltage: 3.3V or 5V
• Operating Frequency Range: Min. 850MHz, Max. 1900MHz
• Operating Temperature Range: Min. -40°C, Max. +85°C

• Schematic
• SARA-R412M Datasheet
• TPS7A7002 Datasheet
• SARA-R412M-AT Commands
• mikroSDK
• GitHub