2 layers
2 layers344.3 × 126.3 mm
KB75
Aahil78/KB756My 4th attempt on making a Mechanical 75% Keyboard
- Size
- 344.3 × 126.3 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 341
- Nets
- 214
- Pads
- 1,361
- Tracks, vias
- 3,617, 620
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 12 Jun 2025
- Updated
- 20 Jul 2025
Overview
KB75 is an open-source printed circuit board by Aahil78, from the Aahil78/KB75 repository on GitHub, published under the GPL-3.0 licence. It is a 2-layer board of 344.3 × 126.3 mm with 341 parts on 214 nets, routed with 3,617 tracks and 620 vias.
It is built around the 74AHCT125D. Its parts include 165 diodes, 82 capacitors, 74 switches and 1 IC. It belongs with the keyboards and input boards and the RP2040 boards of this library.
Main components
1README
README.mdKB75 -- A open-source 75% Keyboard
This is a 75% mechanical keyboard that has per-key rgb, hotswappable keys, an OLED, and a rotary encoder. It's based on the Raspberry Pi Pico so it supports QMK and KMK.
I decided to make this because I love mechanical keyboards but the one I was using broke. And keebs over here just don't got much variety or they are low quality, so I decided to make my own.
Features:
- Open Source
- Hotswappable
- Per-key SK6812MINI-E RGB Backlight
- A rotary encoder
- 75% Layout
- 0.91" Vertical OLED
- Easy to program (depends from person to person)
- QMK and KMK both are supported
- 3D Printed / CNC Case and plate
Images:
Schematic:
PCB:
Case and Plate:
Bill Of Materials
Here's my BOM:
| Item | Quantity | MOQ | LCSC # | Price |
|---|---|---|---|---|
| 0805 Capacitors 100nf | 82 | 100 | C49678 | $0.44 |
| 0805 Resistors 10K ohm | 2 | 100 | C84376 | $0.19 |
| 0805 Diodes | 83 | Multiples of 50 | C82544 | $2.7 |
| Kailh MX Sockets | 82 | Multiples of 10, 30, 70, or 110 | CPG151101S11 | $9.15 |
| Raspberry Pi Pico | 1 | 1 | Raspberry Pi Pico | $1.50 |
| SK6812MINI-E | 82 | Multiples of 5 | C5149201 | $5.02 |
| MX Style Stabilizers | 1 Kit | - | Gateron Stabs | $11.21 |
| 0.91" OLED White | 1 | 5 | 0.91" OLED | $8.86 |
| Si2318CDS-T1-GE3 | 1 | 5 | C14498 | $0.56 |
| MX Style Keycaps | 1 Set | - | Keycaps | $11.85 |
| MX Switches | 82 | Multiples of 10 | Switches | $41.99 |
| EC11 Encoder | 1 | 5 | Encoder | $3.06 |
| EC11 Encoder Knob | 1 | 1 | Knob | $1.18 |
| 74AHCT125 | 1 | 5 | C148198 | $1.12 |
The total cost will be a bit over $124 including PCB, shipping, and filament.
Parts
341| Qty | Value | Footprint | References |
|---|---|---|---|
| 83 | D | Diode_SMD:D_0805_2012Metric_Pad1.15x1.40mm_HandSolder | D1, D2, D10, D11, D12, D13, D14, D15, D16, D17, D18, D19, D20, D21, D22, D23 +67 |
| 82 | C | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C1, C2, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20, C21, C22, C23 +66 |
| 82 | ~ | MX_SK6812MINI-E:MX_SK6812MINI-E | LED1, LED2, LED10, LED11, LED12, LED13, LED14, LED15, LED16, LED17, LED18, LED19, LED20, LED21, LED22, LED23 +66 |
| 3 | MountingHole | Stabilizer_Cherry_MX_2.00u | ST28, ST57, ST59 |
| 2 | Alt | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW75, SW77 |
| 1 | " | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW56 |
| 1 | + | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW27 |
| 1 | , | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW67 |
| 1 | - | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW26 |
| 1 | . | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW68 |
| 1 | / | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW69 |
| 1 | 0 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW25 |
| 1 | 1 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW16 |
| 1 | 2 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW17 |
| 1 | 3 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW18 |
| 1 | 4 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW19 |
| 1 | 5 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW20 |
| 1 | 6 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW21 |
| 1 | 7 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW22 |
| 1 | 74AHCT125 | Package_SO:TSSOP-14_4.4x5mm_P0.65mm | U1 |
| 1 | 8 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW23 |
| 1 | 9 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW24 |
| 1 | ; | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW55 |
| 1 | A | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW46 |
| 1 | B | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW64 |
| 1 | Backspace | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW28 |
| 1 | C | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW62 |
| 1 | Caps Lock | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW45 |
| 1 | D | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW48 |
| 1 | Delete | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW14 |
| 1 | Down Arrow | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW81 |
| 1 | E | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW33 |
| 1 | ESC | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW1 |
| 1 | End | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW72 |
| 1 | Enter | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW57 |
| 1 | F | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW49 |
| 1 | F1 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW2 |
| 1 | F10 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW11 |
| 1 | F11 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW12 |
| 1 | F12 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW13 |
| 1 | F2 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW3 |
| 1 | F3 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW4 |
| 1 | F4 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW5 |
| 1 | F5 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW6 |
| 1 | F6 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW7 |
| 1 | F7 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW8 |
| 1 | F8 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW9 |
| 1 | F9 | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW10 |
| 1 | Fn | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW78 |
| 1 | G | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW50 |
| 1 | H | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW51 |
| 1 | Home | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW29 |
| 1 | I | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW38 |
| 1 | J | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW52 |
| 1 | K | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW53 |
| 1 | L | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW54 |
| 1 | L Ctrl | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW73 |
| 1 | L Shift | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW59 |
| 1 | Left Arrow | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW80 |
| 1 | M | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW66 |
| 1 | MountingHole | Stabilizer_Cherry_MX_6.25u | ST76 |
| 1 | N | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW65 |
| 1 | O | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW39 |
| 1 | P | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW40 |
| 1 | Pg Dn | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW58 |
| 1 | Pg Up | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW44 |
| 1 | Q | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW31 |
| 1 | R | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW34 |
| 1 | R Ctrl | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW79 |
| 1 | R Shift | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW70 |
| 1 | RaspberryPi_Pico | Module:RaspberryPi_Pico_Common_Unspecified | A1 |
| 1 | Right Arrow | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW82 |
| 1 | RotaryEncoder_Switch_MP | Encoders:RotaryEncoder_Alps_EC11E-Switch_Vertical_H20mm | SW83 |
| 1 | S | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW47 |
| 1 | Space | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW76 |
| 1 | T | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW35 |
| 1 | Tab | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW30 |
| 1 | U | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW37 |
| 1 | Up Arrow | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW71 |
| 1 | V | PCM_Switch_Keyboard_Hotswap_Kailh:SW_Hotswap_Kailh_MX_1.00u | SW63 |
The 327 most common of 341 parts.
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Questions
How big is the KB75 PCB?
It measures 344.3 × 126.3 mm and has 2 copper layers, 1.6 mm thick.
What parts does the KB75 use?
341 parts, built around the 74AHCT125D. 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 KB75 KiCad files?
From the Aahil78/KB75 repository on GitHub, at the commit this page was made from: the board is src/KB75.kicad_pcb and its schematic src/KB75.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the KB75 design in my own project?
Its repository publishes it under the GPL-3.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).