RN4020-V/RM123 Bluetooth Low Energy Module: Datasheet, Features, and Application Design Guide
The RN4020-V/RM123 from Microchip Technology is a fully certified Bluetooth Low Energy (BLE) module designed to accelerate product development and reduce time-to-market for IoT and smart device applications. This module integrates a powerful microcontroller, RF transceiver, protocol stack, and unique features into a compact, surface-mount package, providing a robust and reliable wireless connectivity solution.
Key Datasheet Specifications
The module is built around a PIC16LF18456 microcontroller and a proprietary BTLE v4.1 compliant radio. Key electrical specifications include:
Supply Voltage: 1.8V to 3.6V
Transmit Power: Configurable from -20 dBm to +6 dBm
Receiver Sensitivity: -92.5 dBm (typical)
Current Consumption: 4.5 µA (Sleep mode), 9 mA (average connected mode)
I/O Interfaces: UART, SPI, I²C, ADC, and GPIOs
Integrated PCB Antenna
Operating Temperature: -40°C to +85°C
Salient Features
The RN4020 module stands out due to its ease of integration and powerful command-driven interface.
Pre-Certified: FCC, IC, CE, and MIC certified, significantly reducing regulatory testing complexity and cost.
Integrated Stack and Profiles: The module runs the complete BLE protocol stack and supports GAP, GATT, and standard BLE profiles out-of-the-box, including Battery, Device Information, and Transparent UART.
Data Mode and Command Mode: It operates in two primary modes. The simple Data Mode allows for transparent UART communication, making it ideal for upgrading existing wired products. The Command Mode provides full control over all BLE functionalities for custom application development.
128-bit AES Encryption: Built-in hardware encryption ensures secure data transmission, a critical requirement for IoT applications.
Onboard PCB Antenna: Offers a good range and eliminates the need for an external antenna, saving space and BOM cost.
Application Design Guide and Considerations
Integrating the RN4020 module into a design is straightforward. Here are the key steps and considerations:
1. Power Supply: A stable and clean LDO regulator is recommended. Decoupling capacitors must be placed as close to the module's VDD pins as specified in the datasheet.
2. Host Microcontroller Interface: The primary interface is a UART (TX/RX). For basic functionality, only these two pins, along with power and ground, are required to establish a BLE connection.
3. Control Pins: Key pins for control include:
WAKE_IN: Used by the host to wake the module from sleep.
WAKE_OUT: The module uses this to wake up the host microcontroller.
MLDP: Used for firmware updates and entering Command Mode.
4. Configuration: The module is configured using simple ASCII commands over UART (e.g., `SR,
5. PCB Layout: While the module is pre-certified, the host PCB design must ensure stable power and avoid noise on the power rails. Keep digital traces away from the antenna zone on the module.
Typical Applications
The RN4020-V/RM123 is ideal for a vast array of applications, including:
Wireless Sensors (temperature, humidity, pressure)
Health and Fitness Monitors
Smart Home and Automation devices
Proximity and Asset Tracking tags
Remote Controls and HID devices
Industrial IoT sensor nodes
ICGOOODFIND
The RN4020-V/RM123 is a highly integrated and cost-effective solution for developers seeking to add low-power Bluetooth connectivity to their products. Its pre-certified status, simple UART interface, and ultra-low sleep current make it an excellent choice for battery-powered IoT devices, dramatically simplifying the design process and ensuring robust wireless performance.
Keywords: Bluetooth Low Energy (BLE), IoT Module, Pre-Certified, Ultra-Low Power, UART Interface
