Supermini NRF52840

SuperMini NRF52840 is a Pro Micro alternative development board that's BLE ready (compatible with nice!nano). Its pins are the same as ProMicro, which means it can be used with almost any ProMicro keyboard. The NRF5280 development board has a 3.7V lithium battery interface and a software switch that can cut off the power of the LED. When turned off, the standby power consumption can reach 1mA.

nRF52840 is a high-performance, low-power wireless SoC chip launched by Norwegian Nordic Semiconductor. It supports multiple wireless protocols, including Bluetooth 5, Thread, Zigbee, ANT, and 2.4GHz. The nRF52840 chip uses an ARM Cortex-M4F processor, clocked at 64MHz, with built-in 1MB of flash memory and 256KB of RAM. It also has a variety of peripherals, including ADC, PWM, SPI, I2C, UART, USB and GPIO, etc.