Memory
About the Memory PCB
Memory is an open source PCB design by DutchMaker, published on GitHub. It is a 2-layer board measuring 149.2 × 86.4 mm, with 29 components from 16 distinct parts.
Other key parts include the 74x04, 74x00, 74x02, 74x32 and UM61512AK-15. By type, the board carries 10 switches, 9 ICs, 4 connectors, 3 resistors and 2 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 Memory
Memory bill of materials (BOM)
29 components, 16 distinct parts.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | 74x04 | DIP-14_W7.62mm | U1 |
| 1 | 74x00 | DIP-14_W7.62mm | U2 |
| 1 | 74x02 | DIP-14_W7.62mm | U3 |
| 1 | 74x32 | DIP-14_W7.62mm | U4 |
| 1 | UM61512AK-15 | DIP-32_W7.62mm | U5 |
| 1 | 27C512 | ZIF-28_Socket | U6 |
| 3 | 74x245 | DIP-20_W7.62mm | U7, U8, U9 |
| 1 | Conn_01x13_Male | PinHeader_1x13_P2.54mm_Vertical | J1 |
| 1 | Conn_01x16_Male | PinHeader_1x16_P2.54mm_Vertical | J2 |
| 2 | Conn_01x08_Male | PinHeader_1x08_P2.54mm_Vertical | J3, J4 |
| 1 | HDSP-4830_2 | HDSP-4830 | BAR1 |
| 8 | SW_DPDT_x2 | FlipSwitch | SW1, SW2, SW3, SW4, SW5, SW6, SW7, SW8 |
| 2 | SW_DPDT_x2 | Switch | SW9, SW10 |
| 2 | LED | LED_D5.0mm | D1, D2 |
| 2 | 470 | R_Axial_DIN0207_L6.3mm_D2.5mm_P7.62mm_Horizontal | R1, R2 |
| 1 | 470 | R_Array_SIP9 | RN1 |
Memory 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.
Memory: common questions
How big is the Memory PCB?
The Memory measures 149.2 × 86.4 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the Memory?
29 components, from 16 distinct parts. The full bill of materials is listed on this page.
Where can I download the Memory 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 Memory 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.
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