BLE 5.1 MCU with 31 GPIOs — enough I/O for a sensor hub
The Texas Instruments CC2640F128RGZT is a Bluetooth v5.1 wireless MCU from the SimpleLink family, combining a 2.4 GHz transceiver with an ARM Cortex-M3 core. It integrates 128 kB of Flash and 28 kB of SRAM, enough to run the BLE 5.1 protocol stack alongside a moderate application — think environmental sensor nodes, beacons, or simple HID peripherals. The 31 GPIOs mean you can connect multiple sensors, buttons, and LEDs without an external I/O expander, saving board space and BOM cost. Receiver sensitivity is rated at -97 dBm, giving a solid link budget for indoor ranging and asset-tracking applications that need the coded PHY or direction-finding features in v5.1.
The supply voltage spans 1.8 V to 3.8 V, so it can run directly from a single Li-ion cell or two alkaline batteries without an external regulator, though the RF output power (5 dBm typical) will drop at the low end of the range. Current consumption in receive mode sits between 5.9 mA and 6.1 mA; transmit draws 6.1 mA to 9.1 mA depending on output power setting, which matters for battery-life budgeting in coin-cell designs.
Package and layout — 48-VQFN with exposed pad
The CC2640F128RGZT comes in a 48-VFQFN package with an exposed thermal pad (supplier package designation 48-VQFN, 7x7 mm). The part is surface-mount only.
Active lifecycle — no end-of-life concern for new designs
The serial interfaces include I²C, I²S, JTAG, SPI, and UART, covering most sensor and peripheral connectivity needs.