The $4 Raspberry Pi Radio Module 2 Looks to Add SPI-Connected Wi-Fi, Bluetooth to Your Next Project
Based on the same Infineon CYW43439 as the Raspberry Pi Pico W and Pico 2 W, this compact comms module comes pre-certified.
Raspberry Pi has announced the official launch of its Raspberry Pi Radio Module 2 — now available as a standalone product for the first time, priced at just $4.
"Every Raspberry Pi computer since Raspberry Pi 3B+ has been a 'module' from a conformance perspective: because we isolate the radio frequency components under a shield can, you can build your own wireless-enabled product around ours without having to re-certify the radio, saving tens of thousands of dollars," explains Raspberry Pi's Eben Upton. "Today we're building on that heritage with our first stand-alone Wi-Fi and Bluetooth radio module. Priced at just $4, Raspberry Pi Radio Module 2 packages the same Infineon CYW43439 radio used on Raspberry Pi Pico W and Pico 2 W, and is an ideal choice for RP2040- and RP2350-based products that require turnkey wireless connectivity."
As Upton says, the new Radio Module 2 (RM2) is built around the Infineon CYW43439 wireless chip — meaning it includes 1×1 single-band 2.4GHz Wi-Fi 4 and Bluetooth 5.2 connectivity, with the latter supporting both full-fat Bluetooth Classic and the slimmed-down Bluetooth Low Energy. Elsewhere on the module is an integrated power amplifier, low-noise amplifier, and transmit/receive switch — though both Wi-Fi and Bluetooth radios share a single PCB antenna. Interestingly, there's also a built-in general-purpose input/output (GPIO) expander that gives a host device three additional IO pins to play with.
The module uses the same castellated pin headers as the Raspberry Pi Pico family, meaning it can be used with pins or soldered into place as a surface-mount component — the latter approach likely the most common usage, and aided by a lack of components on the underside. There's a low-pin-count SPI host interface, and the promise of full modular certification — meaning it can be added to a design without the need for the resulting device to undergo radio-frequency certification once assembled. 20MHz channels are supported along with an official PHY data rate of 96Mb/s, though real-world throughput is unlikely to reach this theoretical maximum.
More information on the Raspberry Pi Radio Module 2 is available on the Raspberry Pi website along with links to purchase the part, which had previously been available only to partner companies like SparkFun and Pimoroni for use in their own board designs, for just $4 in single-unit quantities.