Clock
About the Clock PCB
Clock is an open source PCB design by ifilot, published on GitHub under the CERN-OHL-S-2.0 license. It is a 2-layer board measuring 101.6 × 55.9 mm, with 72 components from 40 distinct parts.
Other key parts include the SE555, 74HC00, 74HC14, 74HC151 and 74HC02. By type, the board carries 20 capacitors, 17 resistors, 12 ICs, 11 diodes, 8 switches and 2 connectors.
From the project
Modular 8-bit computer built with TTL logic units to create a "Simple as Possible" system
This project showcases the design and construction of a modular 8-bit computer built with TTL logic units. The core principle behind the project is to create a "Simple as Possible" system, focusing on simplicity, modularity, and compactness.
- TTL Logic-Based Design: The computer is built using traditional TTL (Transistor-Transistor Logic) components, adhering to a fundamental, hands-on approach to computing. - Modular Architecture: Designed for modularity, each functional unit (ALU, registers, memory, control logic, etc.) is implemented as a separate module, allowing for easy debugging…
Main components on the Clock
Clock bill of materials (BOM)
72 components, 40 distinct parts.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 2 | SE555 | SOIC-8_3.9x4.9mm_P1.27mm | U1, U9 |
| 4 | 74HC00 | SO-14_3.9x8.65mm_P1.27mm | U2, U5, U8, U11 |
| 1 | 74HC14 | SO-14_3.9x8.65mm_P1.27mm | U3 |
| 1 | 74HC151 | SO-16_3.9x9.9mm_P1.27mm | U4 |
| 1 | 74HC02 | SO-14_3.9x8.65mm_P1.27mm | U6 |
| 3 | 74HC193 | SO-16_3.9x9.9mm_P1.27mm | U7, U10, U12 |
| 1 | TCXO-14 | Oscillator_DIP-14 | X1 |
| 1 | SIGNALS | PinHeader_1x10_P2.54mm_Vertical | J1 |
| 1 | X | PinHeader_1x10_P2.54mm_Vertical | J2 |
| 1 | 1M | Potentiometer_ACP_CA9-V10_Vertical | RV1 |
| 1 | SWS0 | SW_PUSH_6mm | SW1 |
| 1 | Clock Divider | SW_DIP_SPSTx04_Slide_6.7x11.72mm_W8.61mm_P2.54mm_LowProfile | SW2 |
| 1 | SWS1 | SW_PUSH_6mm | SW3 |
| 1 | MANCLK | SW_PUSH-12mm_Wuerth-430476085716 | SW4 |
| 1 | SWS2 | SW_PUSH_6mm | SW5 |
| 1 | Reset Counter | SW_DIP_SPSTx04_Slide_6.7x11.72mm_W8.61mm_P2.54mm_LowProfile | SW6 |
| 1 | CLEAR | SW_PUSH_6mm | SW7 |
| 1 | MANHALT | tactile_button | SW8 |
| 1 | CLK | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D1 |
| 1 | S0 | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D2 |
Show 20 more
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | S1 | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D3 |
| 1 | S2 | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D4 |
| 1 | ~{CLR} | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D5 |
| 1 | CD0 | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D6 |
| 1 | CD1 | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D7 |
| 1 | CD2 | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D8 |
| 1 | CD3 | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D9 |
| 1 | MANHALT | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D10 |
| 1 | HALT | LED_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D11 |
| 2 | 0.01uF | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C1, C6 |
| 1 | 15pF | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C2 |
| 15 | 0.1uF | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C3, C7, C8, C9, C10, C11, C12, C13 +7 |
| 1 | .1uF | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C4 |
| 1 | 1uF | C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C5 |
| 6 | 10k | R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R1, R4, R5, R6, R10, R11 |
| 2 | 1k | R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R2, R3 |
| 4 | 330 | R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R7, R9, R12, R13 |
| 1 | 1M | R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R8 |
| 2 | 10k | R_Array_Convex_4x0603 | RN1, RN3 |
| 2 | 220 | R_Array_Convex_4x0603 | RN2, RN4 |
Clock design files
The KiCad project lives in the ifilot/sap-smd 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 101.6 × 55.9 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the Clock?
72 components, from 40 distinct parts. The full bill of materials is listed on this page.
Where can I download the Clock design files?
From the ifilot/sap-smd repository on GitHub, which has the KiCad layout and the schematic; the links under Design files point to each one.
Can I use the Clock design in my own project?
Yes, under the terms of its CERN-OHL-S-2.0 license, which ifilot chose for the repository.
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