The Texas Instruments CC2640R2FRHBR is a Bluetooth v5.0 wireless MCU from the SimpleLink™ family, integrating a 2.4GHz transceiver with a 32-bit ARM Cortex-M3 core. It carries 128kB of Flash and 28kB of SRAM, enough to run a BLE stack and a moderate application without external memory. The RF front end delivers a -103dBm sensitivity and a 5dBm output power, giving a link budget that works through a couple of interior walls in a smart-home or beacon deployment.
Power budget and battery life
Current draw sits at 5.9mA in receive and 9.1mA in transmit at 5dBm output. For a coin-cell-powered sensor that wakes, sends a packet, and goes back to sleep, those numbers keep the average current low enough for multi-year operation with a CR2032. Supply range from 1.8V to 3.8V means the part runs directly off a lithium primary cell or a 3.3V rail without an extra regulator.
GPIO and serial interface count
Fifteen GPIOs are available, which covers a typical sensor node with an I²C accelerometer, a SPI flash, a UART for debug, and a couple of button/LED lines. The serial interfaces include I²C, I²S, SPI, and UART, so audio streaming or external codec connection is possible without bit-banging.