 Hello, and welcome to this overview of the radio frequency characteristics of the STM32WB microcontroller. The STM32WB is a new family, which combines on the same die, an STM32 microcontroller, and an RF part for connectivity. A radio frequency chain consists of a transmitter to send the signal over the air, and on the other hand, a receiver to acquire this signal. At each side, transmitter and receiver, an antenna is needed to convert the electrical signal to electromagnetic waves on the transmitter side, and conversely, to transform the electromagnetic waves into an electrical signal on the receiver side. The RF transceiver, embedded inside the STM32WB microcontroller, comprises a digital interface, a 32 MHz external crystal isolator for the internal synthesizer used for the modulation, an output input stage, and a dedicated power management circuit. The output stage consists of a power amplifier, or PA. The input stage consists of a low-noise amplifier, or LNA. STM32WB microcontrollers support short-range communication technologies, such as Bluetooth Low Energy, or Bluetooth LE, formerly marketed as Bluetooth Smart, and IEEE 802.15.4, BLE, Thread, and ZigBee. The Bluetooth Special Interest Group, or SIG, is the standards organization that oversees the development of the Bluetooth standards and the licensing of the Bluetooth technologies and trademarks to manufacturers. The SIG is a not-for-profit, non-stock corporation founded in September 1998. STM32WB is certified Bluetooth 5 with the 2 Mbps RF physical layer, or PHY. Thanks to an internal transformer connected to the RF pins, the circuit provides a direct interface for the antenna, single-ended connection, impedance close to 50 ohms. The natural band-pass behavior of the internal transformer simplifies the external circuitry used for harmonic filtering and out-of-band interference rejection. To achieve the best RF performance for both transmission and reception, the use of an external matching network and an integrated low-pass filter, or LPF, is recommended. In receiver mode, a linearized, smooth analog control offers a clean power ramp-up. In receive mode, the circuit can be used in standard high-performance, or in reduced power consumption, or user-programmable mode. The automatic gain control, or AGC, is able to reduce the chain gain at both RF and IF locations for optimized interference rejection. Thanks to the use of complex filtering and highly accurate IQ architecture, high sensitivity and excellent linearity can be achieved. The STM32WB is a dual-core device. The microcontroller has a Cortex-M4 core for the application, and a Cortex-M0-plus core dedicated to the radio. A section of the flash memory is secured for the RF subsystem CPU, that is the Cortex-M0-plus core, and cannot be accessed by the Cortex-M4 core. Both cores can read, write, or erase the embedded flash memory thanks to a dedicated hardware mechanism. The arbitration is based on time-sharing. The STM32WB microcontroller has the same readout protection as the other STM32 microcontrollers with three levels of protection. Level zero gives full access, while level two ensures full protection by fuse, meaning it cannot be undone. Depending on the application, the output power can reach its maximum value of plus 6 dBm with the maximum LDO voltage, or can be reduced to minimize the current consumption. The 32 MHz crystal oscillator does not need an external trimming capacitor network thanks to a dual network of programmable integrated capacitors. To achieve the best RF performance for both transmission and reception, the use of an external matching network and an integrated low-pass filter or LPF is recommended. This slide shows an example of a complete application circuit.