The nRF51822 is a powerful, highly flexible multiprotocol SoC ideally suited for Bluetooth® Smart (previously called Bluetooth low energy) and 2.4GHz ultra low-power wireless applications. The nRF51822 is built around a 32-bit ARM® Cortex™ M0 CPU with 256kB/128kB flash + 32kB/16kB RAM for improved application performance. The embedded 2.4GHz transceiver supports both Bluetooth Smart and the Nordic Gazell 2.4 GHz protocol stack which is on air compatible with the nRF24L series products from Nordic Semiconductor. nRF51822 incorporates a rich selection of analog and digital peripherals that can interact without CPU intervention through the Programmable Peripheral Interconnect (PPI) system. A flexible 31-pin GPIO mapping scheme allows I/O like serial interfaces, PWM and quadrature demodulator to be mapped to any device pin as dictated by PCB requirements. This enables complete design flexibility associated with pin-out location and function. nRF51822 supports Bluetooth® Smart protocol stacks as well as 2.4GHz protocol stacks, including Gazell, both available as downloads. nRF51822 requires a single power supply and gives the user the option of using on chip linear regulators giving a supply range of 1.8-3.6V, a direct 1.8V mode and a on chip DC-DC buck converter giving a supply range of 2.1-3.6V. The use of the DC-DC converter can be dynamically controlled during run time and enables nRF51822 to operate at radio peak currents below 10 mA @ 3V supply (TX @ 0 dBm & RX). nRF51 SDK provides extensive software support for both Bluetooth Smart and 2.4GHz proprietary applications. nRF51822 is available in 6x6mm 48-pin QFN packages and 3 ultra compact wafer-level chip-scale packages (WLCSP). nRF51822 is available in either 256kB or 128kB Flash + 32kB or 16kB RAM variants. Nordic Semiconductor protocol stacks are known as SoftDevices. SoftDevices are pre-compiled, pre-linked binary files. SoftDevices can be programmed in nRF51 series SoCs and are downloadable from the Nordic website. The nRF51822 supports the SoftDevices below (click on the icons for details).