NXP – Kinetis KW41Z Wireless MCU: A Single Chip for Multi-Protocol Connectivity Challenges


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Many designs with wireless capabilities require more than one chip to achieve wireless multi-protocol connectivity. It is becoming more prevalent for new designs of connected end-nodes to support two different wireless protocols that work concurrently, for improved functionality and user experience. This is the way forward for the Internet of Tomorrow (IoT).

As this happens, new challenges surface, such as higher costs, complexity, physical space, security, reliability, power consumption, functionality and user experience. Each requirement and development stage of the design is important, but the chip selection is one of the most critical, as it directly impacts how the present and future product development challenges are tackled.

The Kinetis KW41Z MCU, based on the ARM® Cortex® M0+ core, integrates a 2.4GHz transceiver that enables the use of Bluetooth® low energy (BLE) v4.2 and IEEE® 802.15.4 compliant modem, with up to 512Kb of Flash and up to 128Kb of SRAM – enough memory for networking stacks and custom application – all on a single chip.

Supporting true multi-protocol modes, the Kinetis KW41Z device is an exceptional solution for concurrent communication on two of the most used protocols, BLE v4.2 and 802.15.4 based network, such as ZigBee or Thread, with available certified software stacks. This multi-mode capability enables participation in a mesh network and direct communication with a mobile device for local and remote control and monitoring.

AES-128 accelerator and true random number generator enable more secure designs with fast encryption/decryption utilizing hardware security algorithms for network commissioning and transmissions. Additionally, the Kinetis KW41Z MCU facilitates an integral security strategy with over-the-air (OTA) firmware upgrades for application updates.

And for power optimization requirements, nine low power modes are available. Its buck-boost DC/DC converter, supports voltages from 0.9V to 4.2V, reducing peak current in receive mode to 6.8mA and transmit to 6.1mA – facilitating portable, battery-powered solutions without additional components, while delivering excellent link budget, maximizing communication range with higher immunity to interference.

The Kinetis KW41Z makes it easier to overcome the challenges of multi-protocol designs for the IoT.

Part NumberProduct FamilyFlash/RAM2.4GHz RF Compatibility
MKW41Z256VHT4KW41Z256KB/64KBBLE/Generic FSK/802.15.4 (Supports concurrent operation)
MKW41Z512VHT4KW41Z512KB/128KBBLE/Generic FSK/802.15.4 (Supports concurrent operation)
MKW31Z256VHT4KW31Z256KB/64KBBLE/Generic FSK
MKW31Z512VHT4KW31Z512KB/128KBBLE/Generic FSK

Development ToolsDevelopment Tools
FRDM-KW41ZFreedom development board for Kinetis® KW41Z MCUs with 2.4GHz BLE, generic FSK and 802.15.4 wireless connectivity solutions
USB-KW41ZUSB dongle for sniffer operations for Kinetis KW41Z MCUs with 2.4GHz BLE, generic FSK and 802.15.4 wireless connectivity solutions

Multi-protocol concurrent BLE v4.2 and 802.15.4 radio capabilitySupports concurrent (time slice) operations in a single chip between an 802.15.4 (Thread) and BLE network lowering system cost and complexity
Sensitivity: -95dBm typical BLE -100dBm typical Generic FSK (at 250 kbit/s) -100dBm typical 802.15.4 +3.5dBm maximum output powerHigh link budget improves range and lowers cost by reducing the need for external power amplifiers or low noise amplifiers. Integrated balun enables smaller, simpler RF design and reduces system costs.
6.8mA typical Rx and 6.1mA Tx current with DC-DC activatedSignificantly reduces the power consumption and extends battery life
Excellent selectivity and blockingSignificantly improves operation in harsh 2.4GHz environments such as condominiums and apartments
48MHz ARM Cortex-M0+ core Up to 512KB flash memory Up to 128KB SRAMHigh performance, low power core with adequate memory to run BLE, Generic FSK and Thread® protocol stacks and application
AES-128 Accelerator True random number generatorFast encryption/decryption utilizing hardware security algorithms for network commissioning and transmissions of supported protocols
Buck and Boost DC-DC working from 0.9V to 4.2VSupports a wide range of batteries from single alkaline or coin-cell to Lithium-Ion
16-bit analog-to-digital converter (ADC) 12-bit digital-to-analog converter (DAC) 6-bit high speed analog comparator (CMP)Supports high performance on-chip analog at the MCU level for sensor aggregation and other sophisticated applications
Small 7 x 7 laminate QFNSmaller size and low component count reduces cost
Fast antenna diversity for 802.15.4Allows the hardware to automatically select between two antennas, improving reliability in high interference environments
Compatible with NXP MCU familySoftware protocol stacks, tools and IDE are compatible with the Kinetis MCUs, and integrated in the MCUXpresso software development kit (SDK)