The **u-blox EVK-R5** is an evaluation kit designed for the SARA-R5 series modules, which are LTE-M and NB-IoT cellular solutions. This kit allows developers to test cellular connectivity, security features, and GNSS (Global Navigation Satellite System) integration. Below is a breakdown of the key electronic components and subsystems of the EVK-R5. --- ## 1. Core Module and Connectivity The heart of the evaluation kit is the u-blox SARA-R5 module. | Component | Description | | :--- | :--- | | **SARA-R5 Module** | Supports LTE Cat M1 / NB1 / NB2. It includes the UBX-R5 chipset and hardware-based Secure Cloud functionality. | | **GNSS Integration** | Many EVK-R5 variants include an onboard **u-blox M8** or **M10** GNSS chip for location tracking, accessible via the SARA module. | | **Antenna Connectors** | Two SMA connectors: one for LTE (Cellular) and one for GNSS (Active/Passive). | ## 2. Power Supply System The board is designed to be versatile in how it draws power to simulate real-world battery or industrial conditions. * **Main Power:** DC Jack (typically 9V to 12V) or via USB. * **Voltage Regulators:** Onboard buck converters step down the input voltage to the **3.8V** required by the SARA-R5 module. * **Current Measurement:** The board includes a 3-pin header (J103) that allows an ammeter to be connected to measure the exact power consumption of the module in various sleep/active modes. ## 3. Interfaces and I/O The EVK-R5 acts as a bridge between the cellular module and a PC or microcontroller. ### Communication Ports * **USB Ports:** * *Main USB:* Used for AT commands, data transfer, and firmware updates. * *Two-port Serial-to-USB:* Typically uses an FTDI chip to provide two virtual COM ports (one for data/AT commands and one for GNSS or logging). * **DB9 RS-232:** A standard serial port for industrial equipment interfacing. ### Expansion Headers The kit features two main headers for prototyping: 1. **SARA-R5 Pins:** Access to GPIOs, I2C, SPI, and UART. 2. **Arduino Uno Shield Header:** Allows the attachment of standard Arduino shields to extend functionality (e.g., sensors or displays). ## 4. User Interface Components Physical components for manual interaction and status monitoring: * **LED Indicators:** * *Power:* Indicates the board is energized. * *Cellular Status:* Indicates network registration/activity. * *GNSS Status:* Indicates if a position fix has been achieved. * **Buttons:** * *Power-On:* Manually toggles the SARA module power-on pin. * *Reset:* Hard reset for the module. * **SIM Card Slot:** A standard mini-SIM (2FF) slot located on the underside or side of the board. --- ## 5. Simplified Block Diagram Logic ```mermaid graph LR A[External Power/USB] --> B[Power Management] B --> C[SARA-R5 Module] C <--> D[SIM Card Slot] C <--> E[LTE/GNSS Antennas] C <--> F[USB/RS232 Interface] C <--> G[Arduino Headers] ```