Phyduino Pico Rev A0

Phyduino Pico 2: Rev A0 release summary

Board

Revision	A0 (title block dated 2026-10-16)
Form factor	Arduino Uno R3, 68.58 × 53.34 mm
PCB	4 layers, 1.6 mm, ENIG finish
Design files	KiCad 10.0
Microcontroller	RP2350B (QFN-80), 12 MHz crystal
Memory	16 MB QSPI flash (AT25QF128A), 8 MB PSRAM (IS66WVS8M8FBLL), 8 KB EEPROM (AT24C64D, I²C 0x50)
Analogue	A0–A5 on a 12-bit, 8-channel SPI ADC (ADS7038); AREF on the header; VIN monitored by the RP2350's own ADC
Wireless	ESP32-C6-MINI-1-H4 running ESP-AT over UART0 with RTS/CTS (ESP32-C61-MINI-1 fits the same footprint)
I/O	D0–D15, Qwiic/STEMMA QT (I²C0 on D14/D15), 22-pin HSTX FFC connector, 3-pin SWD, I²C GPIO expander (FXL6408, 0x43)
Power	USB-C 5 V, or barrel jack 4.5–22 V, each through a TPS25947 eFuse (2.6 A limit); AP63301 buck regulators for 3.3 V and 5 V; TPS2121 power mux on the 5 V rail
Reset/boot	One button with a TPS3424: short press resets, holding about 2 s enters UF2 (BOOTSEL) mode

Default header functions:

• serial: UART1 on D0/D1 (GPIO5/4)
• SPI: SPI0 on D10–D13 (GPIO21, 23, 20, 22)
• I²C: I²C0 on D14/D15 (GPIO24/25)

Used on the board itself: UART0 (Wi-Fi), I²C1 (EEPROM, I/O expander, HSTX connector) and SPI1 (ADC).

Release files

• Fabrication: Gerber and drill files in fabrication/. Publishing a GitHub release attaches a zip of them and the schematic PDF.
• Project site (docs/):
  • schematic PDF
  • four copper-layer PDFs with white backgrounds; the bottom layer is mirrored
  • student and full iBOMs
  • STEP and GLB 3D models
  • board renders and the pinout diagram
  • 12 datasheets