FPGA Board for Beginners
- FPGA: Lattice iCE40LP8K (7680 LUTs, BGA-81)
- USB: FT2232HL (Channel A: SPI programming, Channel B: UART)
- Flash: W25Q32 (32Mbit SPI, auto-boot)
- Power: USB 5V -> 3.3V (AMS1117) -> 1.2V (AP2112K)
- GPIO: 2x20 castellated + through-hole pins, 2.54mm pitch (3.3V logic)
- Board: 51mm x 21mm (Raspberry Pi Pico compatible footprint), 2-layer FR4
| Ref | Part | Package | Description | Cost | Buy |
|---|---|---|---|---|---|
| U2 | iCE40LP8K-CM81 | BGA-81 | FPGA 7680 LUTs | $11.55 | digikey |
| U1 | FT2232HL | LQFP-64 | Dual USB-UART/SPI | $8.51 | digikey |
| U3 | MX25L3233F | SOP-8 | 32Mbit SPI Flash | $1.28 | digikey |
| U4-U5 | TPS62A02 | SOT-23-6 | DC-DC Converter | $0.25 | digikey |
| Y1 | ABM8-12.000MHZ-B2-T | 3.2x1.5mm | 12MHz Crystal (18pF) | $0.52 | digikey |
| J1 | USB4085-GF-A | SMD 16pin | USB-C connector | $1.01 | digikey |
| FB1 | BLM21AG601SH1D | 0805 | USB power filter | $0.19 | digikey |
| Ref | Value | Package | Qty | Cost | Notes |
|---|---|---|---|---|---|
| C1-C8 | 100nF | 0402 | 8 | $0.16 | IC decoupling |
| C9-C12 | 10uF | 0805 | 4 | $0.20 | LDO in/out bulk |
| C13-C14 | 18pF | 0402 | 2 | $0.04 | Crystal load caps |
| C15 | 4.7uF | 0603 | 1 | $0.03 | FT2232H VCCORE |
| R1-R2 | 5.1K | 0402 | 2 | $0.02 | USB-C CC pull-down |
| R3 | 12K | 0402 | 1 | $0.01 | FT2232H REF resistor |
| R4 | 10K | 0402 | 1 | $0.01 | CRESET_B pull-up |
| R5-R8 | 1K | 0402 | 4 | $0.04 | LED current limiting |
| D1-D4 | LED | 0603 | 4 | $0.20 | PWR/CDONE/USER x2 |
| SW1-SW2 | Tact | 3x6mm | 2 | $0.20 | Reset/User button |
Toolchain: Yosys + nextpnr-ice40 + icestorm
Programming: iceprog via FT2232H Channel A (MPSSE SPI)