A Raspberry Pi Pico is a microcontroller board, not a small Linux computer: no operating system, no SD card. You flash one program into its on-board flash and it runs from power-on.
The two chips
| RP2040 | RP2350 | |
|---|---|---|
| CPU | 2 × Arm Cortex-M0+ | 2 × Arm Cortex-M33 or 2 × Hazard3 RISC-V (chosen at boot) |
| Max clock | 133 MHz | 150 MHz |
| SRAM | 264 kB | 520 kB |
| Flash | none on chip (external QSPI) | none (RP2350A/B) or 2 MB stacked (RP2354A/B) |
| PIO | 2 blocks × 4 state machines | 3 blocks × 4 state machines |
| Security | — | Arm TrustZone, signed boot, 8 kB OTP, SHA-256, TRNG, encrypted boot |
| Extras | USB 1.1 host/device, 2× UART/SPI/I2C, 16 PWM | same basics, plus HSTX high-speed output, PSRAM support, 16 or 24 PWM |
RP2350 comes in four variants: A packages (QFN-60, 30 GPIO) and B packages (QFN-80, 48 GPIO), each with or without stacked flash.
The boards
| Board | Chip | Flash | Wi-Fi + Bluetooth |
|---|---|---|---|
| Pico / Pico H | RP2040 | 2 MB | no |
| Pico W / Pico WH | RP2040 | 2 MB | yes |
| Pico 2 / Pico 2 with headers | RP2350 | 4 MB | no |
| Pico 2 W / Pico 2 W with headers | RP2350 | 4 MB | yes |
"H" / "with headers" only means pre-soldered pins and a different debug connector. Pinouts of Pico and Pico 2 are the same, as are Pico W and Pico 2 W.
Choosing
- New designs: Pico 2 / Pico 2 W. Twice the SRAM, faster cores, security features, and the option of RISC-V.
- Existing RP2040 code or hardware: Pico / Pico W remain supported by the same SDK.
- Need networking: pick a W model; the wireless chip adds a few quirks (see the Pico W LED and wireless items).
- Battery devices: check the low-power item first. RP2040's deep-sleep current is higher than many expect.