4. Radio system

4.1 Introduction

The system is ultra low power compliant with the Bluetooth® core specification BLE5.4 standard.

The radio system consists of a 2.4 GHz RF front end and a Bluetooth® Low Energy (BLE) physical layer controller. The system is controlled from the CPU2 that contains the radio lower protocol software layers. Interface to the application running on the CPU2 is provided via mailbox message system.

4.2 Main features

4.3 Radio system functional description

4.3.1 General description

The block diagram of the Radio system is shown in Figure 5 .

Figure 5. Radio system block diagram

Figure 5: Radio system block diagram. A complex schematic showing the internal components of the radio system including BLE controller, modulator, demodulator, PLL, PA, LNA, SMPS, and various power management and control blocks. External pins like OSC_IN, OSC_OUT, V_DDSMPS, V_SSSMPS, V_LXSMPS, V_FBSMPS, V_DDRF, and RF1 are shown.

Notes:
- UFQFN48 and UFQFN48E: V SS through exposed pad and V SSRF pin must be connected to ground plane
- WLCSP49: V SSRF pins must be connected to ground plane

Figure 5: Radio system block diagram. A complex schematic showing the internal components of the radio system including BLE controller, modulator, demodulator, PLL, PA, LNA, SMPS, and various power management and control blocks. External pins like OSC_IN, OSC_OUT, V_DDSMPS, V_SSSMPS, V_LXSMPS, V_FBSMPS, V_DDRF, and RF1 are shown.

The maximum default transmit output power can be supported with a default \( V_{\text{FBSMPS}} \) supply level. For higher output power the \( V_{\text{FBSMPS}} \) supply level must be increased (see the device data sheet for more information).