Dialectical Data
~/workshop $ cat ./inventory/raspberry-pi-pico-2-w/README.md

Raspberry Pi Pico 2 W

category
MCU
qty
1
status
owned / untested
maker
Raspberry Pi Ltd
Raspberry Pi Pico 2 W

Overview

The wireless variant of Raspberry Pi’s second-generation Pico board: an RP2350 microcontroller (dual Cortex-M33 or dual RISC-V Hazard3 cores, switchable) paired with an Infineon CYW43439 for WiFi 4 + Bluetooth 5.2, in the same 21×51mm 40-pin DIP-style castellated footprint as the original Pico/Pico W. Alex identified this from a printed third-party pinout reference card (not a photo of the physical board), so intake here started from “part name known” rather than “photo of markings” — specs below are pulled from Raspberry Pi’s own datasheet rather than inferred from the card, though the card’s pin layout was cross-checked and matches.

Key specs

  • Operating voltage: VSYS 1.8V–5.5V (onboard buck-boost SMPS regulates to 3.3V); VBUS (micro-USB) nominally 5V ±10%
  • Logic level: 3.3V fixed on all GPIO (unlike the bare RP2350 chip, which can run I/O down to 1.8V — the Pico 2 W board hardwires it to 3.3V)
  • Current draw: not tabulated in the datasheet in a single figure; ADC draws ~150µA extra when active; wireless/radio draw not specified locally — check RP2350 + CYW43439 datasheets directly if power-budgeting
  • Interfaces: 2×UART, 2×I2C, 2×SPI, 16×PWM channels, 1×HSTX, 3×PIO blocks (12 state machines total, can bit-bang custom protocols e.g. SD card, VGA), 12-bit 500ksps ADC
  • Clock speed / Flash / RAM: RP2350, dual-core (Cortex-M33 or RISC-V Hazard3, selectable) up to 150MHz; 520KB SRAM; flash size has a discrepancy in Raspberry Pi’s own datasheet — see Notes/gotchas
  • Wireless radios: Infineon CYW43439 — WiFi 4 (802.11n, single-band 2.4GHz, WPA3, SoftAP up to 4 clients), Bluetooth 5.2 (LE Central/Peripheral + Bluetooth Classic), connected to the RP2350 via internal SPI (~33MHz), onboard Abracon/ProAnt “Niche” antenna

Pinout

26 of the RP2350’s 30 GPIO are broken out to the 40-pin header (GPIO0–22 digital-only; GPIO26–28 digital or ADC0–2). GPIO23–25 and GPIO29 are reserved internally for the wireless interface and VSYS/3 monitoring (ADC3) and are not on the header. Physical pin numbers below match both the official Raspberry Pi datasheet and the supplied reference card.

Pin # Name Function Notes
1 GP0 UART0 TX, I2C0 SDA, SPI0 RX
2 GP1 UART0 RX, I2C0 SCL, SPI0 CSn
3 GND Ground
4 GP2 I2C1 SDA, SPI0 SCK
5 GP3 I2C1 SCL, SPI0 TX
6 GP4 UART1 TX, I2C0 SDA, SPI0 RX
7 GP5 UART1 RX, I2C0 SCL, SPI0 CSn
8 GND Ground
9 GP6 I2C1 SDA, SPI0 SCK
10 GP7 I2C1 SCL, SPI0 TX
11 GP8 UART1 TX, I2C0 SDA, SPI1 RX
12 GP9 UART1 RX, I2C0 SCL, SPI1 CSn
13 GND Ground
14 GP10 I2C1 SDA, SPI1 SCK
15 GP11 I2C1 SCL, SPI1 TX
16 GP12 UART0 TX, I2C0 SDA, SPI1 RX
17 GP13 UART0 RX, I2C0 SCL, SPI1 CSn
18 GND Ground
19 GP14 I2C1 SDA, SPI1 SCK
20 GP15 I2C1 SCL, SPI1 TX
21 GP16 SPI0 RX, I2C0 SDA, UART0 TX
22 GP17 SPI0 CSn, I2C0 SCL, UART0 RX
23 GND Ground
24 GP18 SPI0 SCK, I2C1 SDA
25 GP19 SPI0 TX, I2C1 SCL
26 GP20 I2C0 SDA
27 GP21 I2C0 SCL
28 GND Ground
29 GP22 General GPIO
30 RUN RP2350 enable/reset Internal ~50kΩ pull-up to 3.3V; short low to reset
31 GP26 ADC0, I2C1 SCL
32 GP27 ADC1, I2C1 SDA
33 GND (AGND) Analog ground Separate analog ground plane for GPIO26–29
34 GP28 ADC2
35 ADC_VREF ADC reference voltage Filtered from 3.3V; can be driven externally for better ADC accuracy
36 3V3(OUT) 3.3V power output Powers RP2350 + I/O; keep external load under 300mA
37 3V3_EN SMPS enable Pulled high via 100kΩ; short to GND to disable 3.3V rail (powers down the whole board)
38 GND Ground
39 VSYS Main system input voltage 1.8–5.5V range, feeds the onboard buck-boost SMPS
40 VBUS USB 5V input From micro-USB pin 1; ~5V, 0V if USB unpowered

Not on the header (internal use only): GPIO23 (wireless power-on), GPIO24 (wireless SPI data/IRQ), GPIO25 (wireless SPI CS), GPIO29 (wireless SPI CLK, doubles as ADC3 for VSYS/3 monitoring). On the CYW43439 side: WL_GPIO0 (drives the onboard user LED), WL_GPIO1 (controls SMPS power-save mode), WL_GPIO2 (VBUS-present sense).

Debug header (separate 3-pin): SWCLK, GND, SWDIO — standard Arm SWD, RP2350 has internal ~60kΩ pull-ups on both signal lines.

Six test points (SMT-module use, not normally needed): TP1 (GND), TP2 (USB D-), TP3 (USB D+), TP4 (SMPS PS pin — do not use externally), TP5 (WL_GPIO0/LED — not recommended for external use), TP6 (BOOTSEL — short low at power-up to force USB mass-storage programming mode, same effect as holding the BOOTSEL button).

Wiring / typical usage

Power via micro-USB for development (also enables USB mass-storage flashing by holding BOOTSEL at power-up). For battery use, feed VSYS directly (1.8–5.5V) — a single Li-ion cell or 3×AA in series both work without extra regulation, thanks to the onboard buck-boost SMPS. GPIO26–29 have a reverse protection diode to the 3.3V rail — don’t feed them more than ~300mV over 3.3V, and don’t apply voltage to them while the board is unpowered (it’ll leak into 3.3V through the diode); GPIO0–25 don’t have this restriction. RUN pin shorted to GND resets the chip in hardware.

Code / libraries

  • Official SDKs: C/C++ SDK (pico-sdk) or MicroPython — Raspberry Pi’s own “Getting started with Raspberry Pi Pico-series” book covers both.
  • Wireless stack (WiFi/Bluetooth) ships as part of the Pico SDK for the CYW43439 (pico_cyw43_arch in C/C++; network module built into MicroPython builds targeting Pico 2 W).
  • Board target strings differ from the original Pico W — make sure build configs/board defs specifically target pico2_w (RP2350), not pico_w (RP2040); they are not interchangeable despite similar names.

Source material

Verification

Verified against the official Raspberry Pi Pico 2 W datasheet (Release 2, 03/07/2026), pulled directly from datasheets.raspberrypi.com. The supplied printed reference card’s pin layout, GPIO functions, and internal/wireless pin assignments all cross-check exactly against the official datasheet — high confidence on the full pinout table above. This entry started from a part name + third-party reference card rather than a photo of the physical unit’s markings, but the primary source used for every spec in this document is Raspberry Pi’s own datasheet, not the card.

Notes / gotchas

  • Flash size discrepancy in Raspberry Pi’s own datasheet: the overview section states “RP2350 microcontroller with 4 MB of flash memory,” but §3.1 (“Programming the flash”) says “the on-board 2 MB QSPI flash can be (re)programmed…” and the components list names the flash chip as Winbond W25Q16JV (a 16Mbit = 2MB part). Third-party listings (Adafruit, Seeed Studio) consistently state 4MB, and 4MB matches the expected “double the Pico W’s 2MB” positioning of the RP2350 generation — so 4MB is very likely correct and the “2MB”/W25Q16JV mentions are a copy-paste leftover from the original Pico W datasheet template. If flash partitioning ever matters for a project, check the actual flash chip marking on the physical board rather than trusting either figure blindly.
  • GPIO26–29 diode protection means these four pins are not 5V-tolerant and shouldn’t be probed while the board is powered off if the signal source is live.
  • I/O is fixed at 3.3V on this board — the bare RP2350 chip itself supports down to 1.8V I/O, but that flexibility isn’t exposed here.
  • Board target name matters: don’t reuse Pico W (RP2040) build configs, board files, or assume identical performance/RAM — this is a different, more capable chip in the same footprint.