LoRa - Wireless RF Semtech SX126x Transceiver Hardware Architecture Introduction

^{SX126x Block Diagram}

introductory

The Semtech SX126x is an ideal sub-GHz radio transceiver (transceivers) designed for long-range wireless applications, supporting transmit power up to +22dBm and maintaining power consumption as low as 20 mA in receive mode. The chip supports LoRa® modulation and (G)FSK modes for Low Power Wide Area Network (LPWAN) and legacy applications, and is compatible with the LoRaWAN® standard and proprietary protocols.

Main components of the SX126x chip and their functions

1.Analog Front End & Data Conversion

• Matching and Low Pass Filter (LPF):
  • Function: Improve the impedance matching between antenna and wafer, reduce signal loss, and improve reception sensitivity.
• Low Noise Amplifier (LNA):
  • Function: To amplify the weak signals received from the antenna and provide high quality input for subsequent data processing.
• Power Amplifier (PA):
  • Function: Increase the output power of the signal when sending information to ensure that the signal can cover a longer distance.
• Phase Locked Loop (PLL) and Oscillator (OSC):
  • Function: Generate a stable clock signal to control the frequency generation and modulation process of the wafer.
• Analog-to-digital converter (ADC)::
  • Function: Converts analog signals to digital signals for signal processing.

2.Modem Module (Modem)

• LoRaData machine:
  • Function: Provides modulation and demodulation of LoRa communication technology to support long range and low power data transmission.
• FSKData machine:
  • Function: Provides frequency shift keying (FSK) modulation demodulation for higher rate application scenarios.

3.Protocol Engine

• Protocol Engine:
  • Function: Logic that handles communication protocols and ensures that information is packaged and parsed correctly.
• Data Buffer:
  • Function: Temporary storage of data to be sent and received to support efficient data processing.

4.power management

• DC-DC Converters and Low Dropout Linear Regulators (LDOs):
  • Function: Provides stable power management and optimizes the energy efficiency of the chip.

5.external interface

• SPICommunication Interface:
  • Function:The datacom connects to the LoRa demodulation-enabled master control unit (MCU) through the SPI interface, ex: ST stm32wle5c8.

application scenario

The SX126x series chips are suitable for a variety of IoT applications that require long-range, low-power communication, including smart agriculture, urban infrastructure management, and environmental monitoring. Its powerful LoRa and FSK features make it ideal for diverse applications in the market.

reach a verdict

The SX126x family of chips is Semtech's technological breakthrough in RF communications. These chips not only integrate a highly efficient analog front-end and diverse modulation and demodulation capabilities such as LoRa® and (G)FSK, but also incorporate advanced data processing to ensure an efficient and reliable communications solution. These features make the SX126x ideal for meeting the demands of today's market for low-power WAN applications.