2 layers197.3 × 121.2 mm
TeensyMaestro Main PCB
rimuadmin/TeensyMaestro-Hardware
Hardware for the TeensyMaestro
115 parts13CERN-OHL-P-2.0
2 layers244.2 × 92.8 mm
Kai simple v3
kaihchang/Kai_Simple_split_keyboard10Kai Simple is a cradio (or some call it Sweep) variation that fits author's hands best. Author's first KB design: https://github.com/kaihchang/Ascendsplaysplitkeyboard
- Size
- 244.2 × 92.8 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 56
- Nets
- 52
- Pads
- 418
- Tracks, vias
- 350, 0
- Pours
- 4
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 1 Apr 2024
- Updated
- 20 Feb 2026
Overview
Kai simple v3 is an open-source printed circuit board by kaihchang, from the kaihchang/Kai_Simple_split_keyboard repository on GitHub. It is a 2-layer board of 244.2 × 92.8 mm with 56 parts on 52 nets, routed with 350 tracks and 0 vias.
It is built around the B5B-XH-A(LF)(SN). Its parts include 34 switches, 2 ICs and 2 connectors.
Main components
1README
README.mdKai Simple, an easy-to-build diodeless, wireless split keyboard
Kai Simple is a cradio (or some call it Sweep) variation that fits author's hands best. Author's first KB design: https://github.com/kaihchang/Ascend_splay_split_keyboard
👉 ZMK config | Dongle-less | With Dongle
MCUs face up for englmaxi's ZMK on-board LED widget. Front-facing built-in LEDs are utilized to present battery and connection status. I use n!n replicas, they only have 1 led each, so sadly no layer change indication.
| Images |
|---|
| New v4 case available! |
 |
I've been using my last Ascend KB for a month, while it is comfortable, MX switches are still relatively big and wide. Maybe it's bc I have small hands or was used to Sweep before it, I started missing Chocs, so that's why there's this Simple. I'll probably stick with ZMK but just in case something went wrong with the power circuits (unlikely), I left a pin for TRRS connectors.
Parts
56| Qty | Value | Footprint | References |
|---|---|---|---|
| 34 | SW_Push | custom_components:Choc_v1v2_pretty | SW1, SW2, SW10, SW11, SW12, SW13, SW14, SW15, SW16, SW17, SW18, SW19, SW20, SW21, SW22, SW23 +18 |
| 2 | B5B-XH-A_LF__SN_ | custom_components:Switch_slide_TH_5P | J1, J2 |
| 2 | Battery_Cell | KLOTZ:JST_PH_reversible | BT1, BT2 |
| 2 | TRRS | ScottoKeebs_Components:TRRS_PJ-320A | U1, U2 |
| 2 | VAL** | Panelization:mouse-bite-3mm-slot | mouse-bite-3mm-slot, mouse-bite-3mm-slot |
| 2 | ~ | custom_components:Pro Micro nRF52840 | Pro_Micro_nRF1, Pro_Micro_nRF2 |
The 44 most common of 56 parts.
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Questions
How big is the Kai simple v3 PCB?
It measures 244.2 × 92.8 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Kai simple v3 use?
56 parts, built around the B5B-XH-A(LF)(SN). 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 Kai simple v3 KiCad files?
From the kaihchang/Kai_Simple_split_keyboard repository on GitHub, at the commit this page was made from: the board is kai_simple_v3.kicad_pcb and its schematic kai_simple_v3.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Kai simple v3 design in my own project?
Its repository states no licence, so its author keeps all rights: ask kaihchang before reusing the design.