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2 layers143.6 × 139.6 mmKazhan oldCopy, the printed circuit board in 3D

Kazhan oldCopy

tikinson/kazhan

custom 28-keys ergonomic mechanical keyboard powered by CH552T microcontroller

Size
143.6 × 139.6 mm
Copper layers
2
Thickness
1.6 mm
Parts
98
Nets
105
Pads
657
Tracks, vias
230, 40
Pours
1
Routed
Yes
KiCad
KiCad 8.0 (file 20240108)
Created
23 Nov 2024
Updated
16 Oct 2026

Overview

Kazhan oldCopy is an open-source printed circuit board by tikinson, from the tikinson/kazhan repository on GitHub, published under the GPL-3.0 licence. It is a 2-layer board of 143.6 × 139.6 mm with 98 parts on 105 nets, routed with 230 tracks and 40 vias.

It is built around the CH552T, USBLC6-2SC6 and PMEG2010EA. Its parts include 34 switches, 19 diodes, 6 resistors, 5 ICs and 3 connectors. It belongs with the 8051 (CH55x, STC, AT89) boards of this library.

Main components

3

README

README.md

🦇Kazhan🦇

projectlogo

WIP. Current PCB is still need a rewiev!

28 Keys. MX and Choc compatible keyboard with CH552T controller. This is the next logical step after my experimental keyboard ToadsTempest.

Idea

Kazhan (Кажан) is derived from the Ukrainian word meaning "bat". As a fan of ZilpZalp/Hummingbird projects i decided make something with same layout but more personalized. Same but different.

first_render

What this project is and what it is not

Goals:

  • A pet project of a keyboard as an act of absolute self-expression.
  • Flexibility and experiments over (and maybe in some case against) minimalistic design approach.
  • Testing interesting "non - conventional" switches as extra keys.
  • Testing things that i don't saw (yet?) in another keyboard PCB designs.

Non-goals:

  • Creation of another variant of the Corne (I like Corne btw, that was my first love in this hobby).
  • Design with a definite assembly variant.
  • Go through the steps in the keyboard design that I have already tried.

Features

  • Mirrored design of PCB to provide split and unibody functionality in one design.
  • Alpsalpine limit switches (SW1, SW2 on schematics) as additional switches. I accidentaly understood, that MX keycap kinda fits on them (with 45 dergee rotation), so i would give them a try.
  • Wired USB-C (USB 2.0) connection.
  • Designed for usage with really affordable chip and F.A.K. firmware.
  • Japanese (duplex) matrix of keys and diodes for them: first of all, it's way more easy to solder one dual diode instead of two regular, because you will never put this part with wrond polarity. And also because of type of key matrix, there is two types of dual diodes: with common anode and common cathode.

Layout

BOM

Opening local copy of ibom.html could save some times while soldering.

ReferenceValueFootprintQtyLCSC
C1, C2100nFCapacitor_SMD:C_0402_1005Metric_Pad0.74x0.62mm_HandSolder2C1525
D1, D4, D5, D8, D9, D11, D13, D15BAS70-06-CAnodePackage_TO_SOT_SMD:SOT-238C8651
D2, D3, D6, D7, D10, D12, D14, D16BAS70-05-CCatodePackage_TO_SOT_SMD:SOT-238C34489
D17PMEG2010EADiode_SMD:D_0402_1005Metric_Pad0.77x0.64mm_HandSolder1C2837790
D18, D19PWR LEDLED_SMD:LED_0402_1005Metric2C130724
F1500mAFuse:Fuse_0402_1005Metric_Pad0.77x0.64mm_HandSolder1C210357
J3USB_C_Receptacle_USB2.0Connector_USB:USB_C_Receptacle_HRO_TYPE-C-31-M-121C2765186
R1, R610kResistor_SMD:R_0402_1005Metric_Pad0.72x0.64mm_HandSolder2C25744
R2, R35.1kResistor_SMD:R_0402_1005Metric_Pad0.72x0.64mm_HandSolder2C25905
R4, R51kResistor_SMD:R_0402_1005Metric2C11702
SW1, SW2~MyFootprintsCollection:SW-TH_SSCF1101002C470322
SW4, SW6RESETKEY-SMD_4P-L4.8-W4.8-P3.70-LS6.4-TL2C2888968
S1–S28KeyswitchSW_Hotswap_Kailh_Choc_MX_1.00u_One_Sided28
U1, U4USBLC6-2SC6Package_TO_SOT_SMD:SOT-23-62C2687116
U2, U3, U5CH552T-- mixed footprints --3C111367
Note: S1-S28 - is footprints for switches. You can choose between MX or Kailh Choc switches (or both if you like experiments) and solder hotswaps accordingly.

Parts

98
QtyValueFootprintReferences
28KeyswitchMyFootprintsCollection:SW_Hotswap_Kailh_Choc_MX_1.00u_One_SidedS1, S2, S10, S11, S12, S13, S14, S15, S16, S17, S18, S19, S20, S21, S22, S23 +12
20SolderJumper_2_OpenMyFootprintsCollection:SolderJumper-1.25x0.5JP3, JP4, JP5, JP10, JP11, JP12, JP13, JP14, JP15, JP16, JP17, JP18, JP19, JP20, JP21, JP22 +4
8BAS70-05-CCatodePackage_TO_SOT_SMD:SOT-23D2, D3, D6, D7, D10, D12, D14, D16
8BAS70-06-CAnodePackage_TO_SOT_SMD:SOT-23D1, D4, D5, D8, D9, D11, D13, D15
5Mounting_HoleMyFootprintsCollection:MountingHole_3.5mmX4.5mm_PadH1, H2, H3, H4, H5
2100nFCapacitor_SMD:C_0402_1005Metric_Pad0.74x0.62mm_HandSolderC1, C2
210kResistor_SMD:R_0402_1005Metric_Pad0.72x0.64mm_HandSolderR1, R6
21kResistor_SMD:R_0402_1005MetricR4, R5
25.1kResistor_SMD:R_0402_1005Metric_Pad0.72x0.64mm_HandSolderR2, R3
2BOOTMyFootprintsCollection:KEY-SMD_4P-L4.8-W4.8-P3.70-LS6.4-TLSW3, SW5
2CH552TPackage_SO:TSSOP-20_4.4x6.5mm_P0.65mmU2, U3
2RESETMyFootprintsCollection:KEY-SMD_4P-L4.8-W4.8-P3.70-LS6.4-TLSW4, SW6
2USBLC6-2SC6Package_TO_SOT_SMD:SOT-23-6U1, U4
2~MyFootprintsCollection:SW-TH_SSCF110100SW1, SW2
1500mAFuse:Fuse_0402_1005Metric_Pad0.77x0.64mm_HandSolderF1
1AudioJack4MyFootprintsCollection:PJ-320A-REVERSIBLE-B.Cu-placingJ2
1AudioJack4MyFootprintsCollection:PJ-320A-REVERSIBLE-F.Cu-placingJ1
1CH552TMyFootprintsCollection:TSSOP-20_4.4x6.5mm_P0.65mm-REVERSIBLEU5
1LOGOMyFootprintsCollection:kazhantest2_1_1_1G***
1PMEG2010EADiode_SMD:D_0402_1005Metric_Pad0.77x0.64mm_HandSolderD17
1PWR LEDLED_SMD:LED_0402_1005MetricD18
1SolderJumper_2_OpenJumper:SolderJumper-2_P1.3mm_Open_RoundedPad1.0x1.5mmJP24
1SolderJumper_2_OpenMyFootprintsCollection:SolderJumper-F.Cu-B.CuJP23
1USB_C_Receptacle_USB2.0Connector_USB:USB_C_Receptacle_HRO_TYPE-C-31-M-12J3
1USR LEDLED_SMD:LED_0402_1005MetricD19

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Questions

How big is the Kazhan oldCopy PCB?

It measures 143.6 × 139.6 mm and has 2 copper layers, 1.6 mm thick.

What parts does the Kazhan oldCopy use?

98 parts, built around the CH552T, USBLC6-2SC6 and PMEG2010EA. 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 Kazhan oldCopy KiCad files?

From the tikinson/kazhan repository on GitHub, at the commit this page was made from: the board is kazhan_oldCopy.kicad_pcb and its schematic kazhan.kicad_sch. PCBKit opens the board in the browser, with nothing to install.

Can I use the Kazhan oldCopy 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).