2 layers
Ya4b alu
lafehubert/electronics
A place for info and code relating to my electronics projects
133 parts
2 layers83.6 × 45.1 mm
Slow clock
lafehubert/electronicsA place for info and code relating to my electronics projects
- Size
- 83.6 × 45.1 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 26
- Nets
- 40
- Pads
- 128
- Tracks, vias
- 294, 6
- Pours
- 2
- Routed
- Yes
- KiCad
- KiCad 5 (file 20171130)
- Created
- 19 Oct 2019
- Updated
- 8 Jan 2022
Overview
Slow clock is an open-source printed circuit board by lafehubert, from the lafehubert/electronics repository on GitHub. It is a 2-layer board of 83.6 × 45.1 mm with 26 parts on 40 nets, routed with 294 tracks and 6 vias.
It is built around the 74HCT00D, 74LS123FP-E and 74LS14PC, with the 74LS32SC among its other parts. Its parts include 8 capacitors, 7 resistors, 6 ICs, 2 switches and 1 diode. It belongs with the lEDs and displays boards of this library.
Main components
4
74HCT00D
SO-14-40℃~+125℃ 100mV、400mV 12ns@4.5V,50pF 2 2V 3.7V、4.4V 4 4.5V~5.5V 40uA 4mA 4mA 74HCT Series 800mV NAND Gate Overvoltage-tolerant input TTL Compatible CMOS SO-14 Logic Gates ROHSNexperiaLogic Gates74LS123FP-E
-Reset input、Adjustable pulse width、Retriggerable function - Monostable Multivibrators ROHSRenesas ElectronicsMonostable Multivibrators
74LS14PC
PDIP-14InvertersTexas Instruments
74LS32SC
-- Logic Gates ROHSTexas InstrumentsLogic Gates
README
ya4b/slow-clock/README.mdThis slow clock was initially inspired by Ben Eater's design (https://eater.net/8bit/clock) but I found the 555 to be too fiddly for the monostable stage, and overkill for the bistable stage, so I used a 74LS123 for the former and an R-S latch made from a couple of NANDs on a 74LS00 for the latter. I also replaced the 74LS04 with a 74LS14 which seemed to clean up the waveform a good bit.
Parts
26| Qty | Value | Footprint | References |
|---|---|---|---|
| 5 | 0.1 µF | Capacitor_THT:C_Disc_D3.8mm_W2.6mm_P2.50mm | C4, C5, C6, C7, C8 |
| 3 | 10 kΩ | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R4, R6, R7 |
| 2 | 1 kΩ | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R1, R2 |
| 2 | 1 µF | Capacitor_THT:C_Disc_D3.8mm_W2.6mm_P2.50mm | C2, C3 |
| 1 | 0.01 µF | Capacitor_THT:C_Disc_D3.8mm_W2.6mm_P2.50mm | C1 |
| 1 | 1 MΩ | Potentiometer_THT:GM_Small_Square_9mm_Pot | RV1 |
| 1 | 330 Ω | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R5 |
| 1 | 74HCT00 | Package_DIP:DIP-14_W7.62mm_Socket | U5 |
| 1 | 74LS08 | Package_DIP:DIP-14_W7.62mm_Socket | U3 |
| 1 | 74LS123 | Package_DIP:DIP-16_W7.62mm_Socket | U4 |
| 1 | 74LS14 | Package_DIP:DIP-14_W7.62mm_Socket | U2 |
| 1 | 74LS32 | Package_DIP:DIP-14_W7.62mm_Socket | U6 |
| 1 | 820 kΩ | Resistor_THT:R_Axial_DIN0207_L6.3mm_D2.5mm_P10.16mm_Horizontal | R3 |
| 1 | Blue 3mm LED | LED_THT:LED_D3.0mm | D1 |
| 1 | Conn_01x06_Male | Connector_PinHeader_2.54mm:PinHeader_1x06_P2.54mm_Vertical | J1 |
| 1 | LM555 | Package_DIP:DIP-8_W7.62mm_Socket | U1 |
| 1 | SW_Push | Button_Switch_THT:SW_PUSH_6mm | SW1 |
| 1 | SW_SPDT | Button_Switch_THT:GM_SPDT_Slide_Switch | SW2 |
Questions
How big is the Slow clock PCB?
It measures 83.6 × 45.1 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Slow clock use?
26 parts, built around the 74HCT00D, 74LS123FP-E, 74LS14PC and 74LS32SC. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Slow clock KiCad files?
From the lafehubert/electronics repository on GitHub, at the commit this page was made from: the board is ya4b/slow-clock/slow-clock.kicad_pcb. PCBKit opens the board in the browser, with nothing to install.
Can I use the Slow clock design in my own project?
Its repository states no licence, so its author keeps all rights: ask lafehubert before reusing the design.
More from lafehubert/electronics
6- 4 layers114.3 × 90.3 mm
Address register bank
lafehubert/electronics
A place for info and code relating to my electronics projects
99 parts - 4 layers100.2 × 81.9 mm
- 4 layers99.6 × 59.1 mm
Data register bank
lafehubert/electronics
A place for info and code relating to my electronics projects
57 parts - 2 layers99.5 × 49.7 mm
Transfer register board
lafehubert/electronics
A place for info and code relating to my electronics projects
40 parts - 2 layers98.8 × 46.7 mm
Ram-32-word
lafehubert/electronics
A place for info and code relating to my electronics projects
32 parts
Similar boards
- 2 layers160 × 100 mm
- 2 layers99.7 × 149.9 mm
- 2 layers
Rogelio Pineda part 7-AMLDC-2044B
ForgottenMachines/Entrex
The technologies documented here will include all like-kind systems manufactured by Nixdorf, Redifon, ROCC & Mera, all originally designed by Entrex Inc, Burlington, MA USA.
332 parts1 - 2 layers253.2 × 203 mm
Pegasus2023
NeilsVintageComputers/1981_Aamber-Pegasus-2023-Revival
My first computer, this is a replica I produced from the original schematics using original old components.
156 partsUnlicense - 2 layers150 × 110 mm
Hobgoblin v2
iley/hobgoblin
Single-board 8-bit computer capable of running CP/M. Inspired by RC2014 and computers by Grant Searle and Sergey Kiselev.
56 parts - 2 layers301.5 × 367.3 mm
OSI 600D Superboard II Cherry Solder Mask
Bambelweeny57/OSI-600D-SuperBoard-II
KiCad 10 recreation of the Ohio Scientific Superboard II Model 600 rev D (1980) with Cherry MX keyswitches, 27C16/2816 ROMs, full schematic and assembly guide.
314 parts - 2 layers229.9 × 86.4 mm
- 2 layers98.3 × 107.1 mm
Coco9511pak
barberd/coco9511pak
This board is a cartridge for the Tandy Radio Shack TRS-80 Color Computer (CoCo), an 8 bit computer produced between 1980 and 1991. It provides an Arithmetic Processor Unit (APU), the AMD 9511, to the CoCo.
44 parts13GPL-3.0