Td4
About the Td4 PCB
Td4 is an open source PCB design by nanamitm, published on GitHub. It is a 2-layer board measuring 97.8 × 97.2 mm, with 100 components from 12 distinct parts.
By type, the board carries 48 resistors, 33 diodes and 19 capacitors.
From the project
TD4 4-bit CPU (from the book CPUの創りかた) as a KiCad 10 hierarchical schematic
A KiCad 10 hierarchical schematic of the TD4, the 4-bit CPU from the book CPUの創りかた (“How to Build a CPU”), transcribed from the published drawing by M. Yamamoto: xyama.sakura.ne.jp / 4bitCPU_TD4.
- 15 ICs, an external-ROM interface, and a 4-bit data path - The 74HC10 and 74HC540 of the original are replaced by more readily available parts, following cuboktahedron's note: a 74HC00 (plus one spare NAND as the inverter) and two 74HC04s - Traced pixel by pixel from 4bitCPUTD4x.gif — wires, junction dots, IC outlines and pin numbers - ERC: 0 errors and one intentional D5 / SELB net-label warning
Td4 bill of materials (BOM)
100 components, 12 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 25 | XL-1608SURC-06 Red XINGLIGHT | LED_0603_1608Metric | D1, D8, D9, D10, D11, D12, D13, D14 +17 |
| 4 | XL-1608UGC-04 Red XINGLIGHT | LED_0603_1608Metric | D2, D3, D28, D29 |
| 4 | XL-1608UYC-06 Yellow XINGLIGHT | LED_0603_1608Metric | D4, D5, D6, D7 |
| 18 | CC0603KRX7R9BB104 100n YAGEO | C_0603_1608Metric | C5, C6, C7, C8, C9, C10, C11, C12 +10 |
| 1 | CL10B102KB8NNNC 1n Samsung Electro-Mechanics | C_0603_1608Metric | C22 |
| 35 | 1k | R_0603_1608Metric | R1, R2, R12, R13, R14, R15, R16, R17 +27 |
| 2 | 1M | R_0603_1608Metric | R3, R46 |
| 4 | 100K 100k | R_0603_1608Metric | R4, R8, R9, R47 |
| 2 | 10K 10k | R_0603_1608Metric | R5, R45 |
| 1 | C23137 330k *1 | R_0603_1608Metric | R6 |
| 1 | C4216 33k *2 | R_0603_1608Metric | R7 |
| 3 | 100 | R_0603_1608Metric | R10, R11, R48 |
Td4 design files
The KiCad project lives in the nanamitm/td4-kicad repository on GitHub; these links point at the commit this page was built from.
Td4: common questions
How big is the Td4 PCB?
The Td4 measures 97.8 × 97.2 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the Td4?
100 components, from 12 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the Td4 design files?
From the nanamitm/td4-kicad repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the Td4 design in my own project?
The repository has no license, so all rights stay with nanamitm. Use it as a reference, and ask the author before reusing the design.