2 layers99.1 × 99.1 mm
2 layers99.1 × 99.1 mm
Ram unit
ksmonkey123/8bit_computer1custom 8bit microprocessor project
- Size
- 99.1 × 99.1 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 25
- Nets
- 52
- Pads
- 238
- Tracks, vias
- 655, 19
- Pours
- 3
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 10 Dec 2024
- Updated
- 9 Sep 2026
Overview
Ram unit is an open-source printed circuit board by ksmonkey123, from the ksmonkey123/8bit_computer repository on GitHub, published under the MIT licence. It is a 2-layer board of 99.1 × 99.1 mm with 25 parts on 52 nets, routed with 655 tracks and 19 vias.
It is built around the 74HC138 and 74HC14. Its parts include 8 capacitors, 6 ICs, 3 resistors and 2 transistors.
Main components
2
74HC138
SOP-160℃~+70℃ 24ns@5.0V,16pF 2V~6V 3/8 5.2mA 5.2mA 5uA 74HC Decoder Reverse function Single Supply SOP-16 Signal Switches, Multiplexers, Decoders ROHSGRSignal Switches, Multiplexers, Decoders
74HC14
SOP-14-40℃~+85℃ 1.9V、3.98V、4.4V、5.48V、5.9V 100mV、260mV、260mV 20uA 25ns@4.5V,50pF 2V~6V 6 74HC Noise suppression function Schmitt trigger SOP-14 Inverters ROHSJSMSEMIInverters
Parts
25| Qty | Value | Footprint | References |
|---|---|---|---|
| 5 | C | Capacitor_SMD:C_0603_1608Metric | C2, C3, C4, C5, C6 |
| 4 | MountingHole_Pad | MountingHole:MountingHole_3.2mm_M3_Pad_Via | H1, H2, H3, H4 |
| 4 | ~ | Package_DIP:DIP-28_W7.62mm_LongPads | U1, U2, U3, U4 |
| 2 | 100nF | Capacitor_SMD:C_0603_1608Metric | C7, C8 |
| 2 | 150R | Resistor_SMD:R_0603_1608Metric | R1, R2 |
| 2 | 2N7000 | Package_TO_SOT_THT:TO-92_Inline_Wide | Q1, Q2 |
| 2 | Conn_01x16 | Connector_IDC:IDC-Header_2x08_P2.54mm_Horizontal | ADDRESS_BUS1, DATA_BUS1 |
| 1 | 1k | Resistor_SMD:R_0603_1608Metric | R3 |
| 1 | 74HC138 | Package_DIP:DIP-16_W7.62mm_LongPads | U5 |
| 1 | 74HC14 | Package_DIP:DIP-14_W7.62mm | U7 |
| 1 | C_Polarized | Capacitor_SMD:CP_Elec_5x5.3 | C1 |
Questions
How big is the Ram unit PCB?
It measures 99.1 × 99.1 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Ram unit use?
25 parts, built around the 74HC138 and 74HC14. 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 Ram unit KiCad files?
From the ksmonkey123/8bit_computer repository on GitHub, at the commit this page was made from: the board is circuits/pc-07_ram_unit/ram_unit.kicad_pcb and its schematic circuits/pc-01_dual_8bit_register/dual_8bit_register.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Ram unit design in my own project?
Its repository publishes it under the MIT licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
More from ksmonkey123/8bit_computer
12- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
- 2 layers99.1 × 99.1 mm
Similar boards
- 2 layers208 × 110 mm
- 2 layers254 × 160 mm
- 2 layers225.1 × 167.8 mm
- 2 layers80 × 75 mm
- 2 layers238.8 × 120.6 mm
- 4 layers251.5 × 116.8 mm
- 2 layers254 × 110.5 mm
- 2 layers234 × 100 mm
V2b
KITTY-6502/hardware
the KITTY is a 65c02 homebrew kit microcomputer designed around text mode graphics and cartridge media. It is fully open source, and uses exclusively in-production parts.
147 parts