Clock
About the Clock PCB
Clock is an open source PCB design by DutchMaker, published on GitHub. It is a 2-layer board measuring 76.2 × 68.6 mm, with 38 components from 18 distinct parts.
Other key parts include the 74x04, 555, 74x08 and 74x32. By type, the board carries 13 resistors, 8 ICs, 6 capacitors, 4 connectors, 3 switches and 3 diodes.
From the project
Building a computer from scratch using 74xx logic chips
- Add ./Libraries/74xx-Computer-Symbols.lib as global Symbol library to KiCad (Eeschema) - Add ./Libraries as global Footprint library to KiCad (Pcbnew) - PCBs are initially autorouted using ./Libraries/freeRouting.jar and traces are enhanced manually
There are a number of deviations and errors that were found in schematic/PCB designs after PCB production. They are listed here if they were not fixed in the schematic/PCB design files.
Main components on the Clock
Clock bill of materials (BOM)
38 components, 18 distinct parts.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | 74x04 | DIP-14_W7.62mm | U1 |
| 4 | 555 | DIP-8_W7.62mm | U2, U6, U7, U8 |
| 2 | 74x08 | DIP-14_W7.62mm | U3, U5 |
| 1 | 74x32 | DIP-14_W7.62mm | U4 |
| 1 | 1 MHz | Oscillator_DIP-8_v2 | Y1 |
| 1 | Conn_01x05_Male | PinHeader_1x05_P2.54mm_Vertical | J1 |
| 3 | Conn_01x02_Male | PinHeader_1x02_P2.54mm_Vertical | J2, J3, J4 |
| 1 | SW_Push | SW_6mm_Tact | SW1 |
| 2 | SW_Push_SPDT | Switch | SW2, SW3 |
| 3 | LED | LED_D5.0mm | D1, D2, D3 |
| 1 | 1uF | CP_Radial_D5.0mm_P2.50mm | C1 |
| 4 | 10nF | C_Rect_L4.6mm_W2.0mm_P2.50mm_MKS02_FKP02 | C2, C3, C5, C6 |
| 1 | 100nF | C_Rect_L4.6mm_W2.0mm_P2.50mm_MKS02_FKP02 | C4 |
| 7 | 1K | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R1, R4, R5, R8, R9, R10, R11 |
| 1 | 47K | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R2 |
| 1 | 1M | Potentiometer_Piher_PT-6-V_Vertical | R3 |
| 1 | 1M | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R6 |
| 3 | 330 | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R7, R12, R13 |
Clock design files
The KiCad project lives in the DutchMaker/TTL-computer repository on GitHub; these links point at the commit this page was built from.
Clock: common questions
How big is the Clock PCB?
The Clock measures 76.2 × 68.6 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the Clock?
38 components, from 18 distinct parts. The full bill of materials is listed on this page.
Where can I download the Clock design files?
From the DutchMaker/TTL-computer repository on GitHub, which has the KiCad layout; the links under Design files point to each one.
Can I use the Clock design in my own project?
The repository has no license, so all rights stay with DutchMaker. Use it as a reference, and ask the author before reusing the design.
More boards in TTL-computer
Controller
191.1 × 114.3 mm60 parts2LNo license23
Main-Board
286.4 × 484.5 mm58 parts2LNo license23
Memory-Access-Register
144.8 × 114.3 mm39 parts2LNo license23
ALU
132.1 × 86.4 mm30 parts2LNo license23
Memory
149.2 × 86.4 mm29 parts2LNo license23
Flags-Register
76.2 × 55.9 mm16 parts2LNo license23
Program-Counter
81.3 × 82.6 mm15 parts2LNo license23
Stack-Pointer
81.3 × 50.8 mm9 parts2LNo license23
Register
55.9 × 52.1 mm7 parts2LNo license23
Instruction-Register
53.3 × 52.1 mm6 parts2LNo license23