4 layers100 × 100 mm
Kvm switch
Rithvik-Vadlamani/kvm-switch
Four-layer HDMI/USB KVM design with STM32 firmware, supply supervision, and verification evidence
170 parts
4 layers227.5 × 75.2 mm
Nehan42
skeletonkbd/NehanMinimal 30% keyboard PCB and Case Project
- Size
- 227.5 × 75.2 mm
- Copper layers
- 4
- Thickness
- 1.6 mm
- Parts
- 183
- Nets
- 171
- Pads
- 756
- Tracks, vias
- 1,592, 447
- Pours
- 4
- Routed
- Yes
- KiCad
- KiCad 9.0 (file 20241229)
- Created
- 20 Nov 2025
- Updated
- 9 Jan 2026
Overview
Nehan42 is an open-source printed circuit board by skeletonkbd, from the skeletonkbd/Nehan repository on GitHub, published under the CERN-OHL-S-2.0 licence. It is a 4-layer board of 227.5 × 75.2 mm with 183 parts on 171 nets, routed with 1,592 tracks and 447 vias.
It is built around the RP2040, IS31FL3236A-QFLS2-TR and W25Q32JVUUIQ, with the TPS2051CDBVR, XC6206P332MR and 1N4148W among its other parts. Its parts include 42 diodes, 42 switches, 31 capacitors, 12 resistors and 6 ICs. It belongs with the RP2040 boards of this library.
Main components
12
RP2040
LQFN-56(7x7)12bit 133MHz 30 LQFN-56(7x7) Microcontrollers (MCU/MPU/SOC) ROHSRaspberry PiMicrocontrollers (MCU/MPU/SOC)
IS31FL3236A-QFLS2-TR
QFN-44-EP(5x5)-40℃~+85℃ 2.7V~5.5V 38mA 400kHz 9mA I²C PWM dimming、Internal reset function QFN-44-EP(5x5) Digital Tube Drivers ROHSISSIDigital Tube Drivers
W25Q32JVUUIQ
USON-8(3x4)-40℃~+85℃ 100,000 cycles 10uA 133MHz 2.7V~3.6V 20 Years 32Mbit Power-on reset、Hardware write protection、Software write protection、Write enable latch、Absolute write protection SPI USON-8(3x4) NOR FLASH ROHSWinbond ElecNOR FLASH
TPS2051CDBVR
SOT-23-5-40℃~+125℃ 100nA 2.5V~5.5V 3.8A Not supported Not supported Soft-start、Under-voltage lockout、Overcurrent Protection、Short-Circuit Protection、Reverse current blocking、Overvoltage protection、Output discharge function SOT-23-5 Power Distribution Switches ROHSTECH PUBLICPower Distribution Switches
XC6206P332MR
SOT-23-40℃~+85℃@(Ta) 1 1uA 200mA 3.3V 6V Fixed Over Current Protection Positive SOT-23-3L Voltage Regulators - Linear, Low Drop Out (LDO) Regulators ROHSTorex SemiconductorVoltage Regulators - Linear, Low Drop Out (LDO) Regulators
1N4148W
SOD-123150mA 1A 1V@50mA 1uA@75V 400mW 4ns 75V Independent SOD-123 Switching Diodes ROHSSTMicroelectronicsSwitching Diodes
XL-3215UWC
SMD,3.2x1.3mmLED Indication - DiscreteXINGLIGHT
CPG151101S11-16
SMD- Mechanical Keyboard Shaft ROHSKailhMechanical Keyboard Shaft
CL31A106KBHNNNE
120610uF 50V X5R ±10% 1206 Multilayer Ceramic Capacitors MLCC - SMD/SMT ROHSSamsung Electro-MechanicsMultilayer Ceramic Capacitors MLCC - SMD/SMTCL31A226KAHNNNE
120622uF 25V X5R ±10% 1206 Multilayer Ceramic Capacitors MLCC - SMD/SMT ROHSSamsung Electro-MechanicsMultilayer Ceramic Capacitors MLCC - SMD/SMT
TS-1187A-B-A-B
SMD-4P,5.1x5.1mm-30℃~+85℃ 1.5mm 1.6N 100,000 cycles 12V 5.1mm 5.1mm 50mA Gold No Round Button SPST Surface Mount,Vertical Without Bracket SMD-4P,5.1x5.1mm Tactile Switches ROHSXKB ConnectionTactile Switches
X322512MSB4SI
SMD3225-4P-40℃~+85℃ 12MHz 20pF 80Ω Crystal Oscillator ±10ppm ±20ppm SMD3225-4P Crystals ROHSYXCCrystals
README
Nehan42 PCB/README.mdRP2040_KiCad_template
※ 現時点ではまだ基板を製造しての実機確認は行っていません。もしご利用される場合は自己責任でお願いいします。
これはなに？
RP2040周りの回路図をKiCadで作成したものです。プロジェクトテンプレートとして使用することを想定しています。
JLCPCBでPCBAをするための部品の選定も行っています。
使用方法
ユーザーテンプレートフォルダのパスの確認・変更
KiCadで設定からパスを設定を開きます。
KICAD_USER_TEMPLATE_DIRのパスを確認、必要に応じて変更します。
このディレクトリを配置します。
テンプレートから新規プロジェクトを作成
ファイルからテンプレートから新規プロジェクトを開きます。
ユーザーテンプレートに「RP2040 Template」という表示が現れますので、それを選択してOKをクリックします。
BOM
| MNP | メーカー | 用途・概要 | LCSC | 数量 | Basic Parts |
|---|---|---|---|---|---|
| RP2040 | Raspberry Pi | マイコン (メイン MCU) | C2040 | 1 | |
| TYPE-C-31-M-12 | Korean Hroparts Elec | USB Type-C レセプタクル | C165948 | 1 | |
| USBLC6-2SC6 | TECH PUBLIC | USB 信号ライン用 ESD 保護 IC | C2827654 | 1 | |
| W25Q32JVUUIQ | Winbond Elec | フラッシュストレージ (4MB) | C2999380 | 1 | |
| XC6206P332MR-G | Torex Semicon | LDO レギュレーター (3.3V 出力) | C5446 | 1 | 👍️ |
| nSMD050-24V | TECHFUSE | ヒューズ | C70076 | 1 | |
| X322512MSB4SI | YXC Crystal Oscillators | 水晶発振子 12MHz | C9002 | 1 | 👍️ |
| TS-1187A-B-A-B | XKB Connection | タクトスイッチ | C318884 | 2 | 👍️ |
| ESD5Z5V0 | MDD (Microdiode Semiconductor) | 電源ライン用 ESD 保護ダイオード | C502546 | 1 | |
| CL10C220JB8NNNC | Samsung Electro-Mechanics | コンデンサー 22pF | C1653 | 2 | 👍️ |
| CL05B104KO5NNNC | Samsung Electro-Mechanics | コンデンサー 100nF | C1525 | 10 | 👍️ |
| CL05A105KA5NQNC | Samsung Electro-Mechanics | コンデンサー 1µF | C52923 | 4 | 👍️ |
| CL05A106MQ5NUNC | Samsung Electro-Mechanics | コンデンサー 10µF | C15525 | 1 | 👍️ |
| 0603WAF1001T5E | UNI-ROYAL (Uniroyal Elec) | 抵抗 1kΩ | C21190 | 2 | 👍️ |
| 0603WAF5101T5E | UNI-ROYAL (Uniroyal Elec) | 抵抗 5.1kΩ | C23186 | 2 | 👍️ |
| 0603WAF270JT5E | UNI-ROYAL (Uniroyal Elec) | 抵抗 27Ω | C25190 | 2 |
参考資料
RP2040を使用したハードウェア設計
https://datasheets.raspberrypi.com/rp2040/hardware-design-with-rp2040-JP.pdf
「2.1.2. バイパスコンデンサー」のサンプル回路を参考に、コンデンサーの個数を決定しています。配置については回路図内に注記しています。
Hardware design for the RP2040
https://github.com/calliah333/RP2040-designguide/tree/main
主要なパーツの選定の参考にしています。
Xiao RP2040 回路図
https://files.seeedstudio.com/wiki/XIAO-RP2040/res/Seeed-Studio-XIAO-RP2040-v1.3.pdf
ResetとBootの2つのスイッチを配置する方式はXiao RP2040の設計を参考にしています。
Parts
183| Qty | Value | Footprint | References |
|---|---|---|---|
| 42 | 1N4148W | Diode_SMD:D_SOD-123 | D1, D2, D10, D11, D12, D13, D14, D15, D16, D17, D18, D19, D20, D21, D22, D23 +26 |
| 42 | XL-3215UWC | easyeda2kicad:LED-SMD_L3.2-W1.3-RD_GREEN-MHT151UGCT | BL1, BL2, BL10, BL11, BL12, BL13, BL14, BL15, BL16, BL17, BL18, BL19, BL20, BL21, BL22, BL23 +26 |
| 32 | SW_Push | MX_Hotswap:MX-Hotswap-1U | SW1, SW2, SW10, SW11, SW12, SW14, SW15, SW16, SW17, SW18, SW19, SW20, SW21, SW22, SW25, SW26 +16 |
| 13 | 100nF | Capacitor_SMD:C_0402_1005Metric | C1, C3, C10, C11, C12, C13, C14, C15, C16, C18, C20, C21, C23 |
| 6 | 1uF | Capacitor_SMD:C_0402_1005Metric | C2, C4, C6, C7, C17, C19 |
| 6 | SW_Push | MX_Hotswap:MX-Hotswap-1.25U | SW13, SW34, SW35, SW36, SW41, SW42 |
| 5 | 10uF | Capacitor_SMD:C_1206_3216Metric | C8, C28, C29, C30, C31 |
| 4 | 22uF | Capacitor_SMD:C_1206_3216Metric | C24, C25, C26, C27 |
| 4 | 4.7k | Resistor_SMD:R_0603_1608Metric | R2, R3, R5, R6 |
| 4 | MountingHole | MountingHole:MountingHole_2.2mm_M2_DIN965_Pad_TopOnly | H1, H2, H3, H4 |
| 3 | 10k | Resistor_SMD:R_0603_1608Metric | R1, R4, R12 |
| 2 | 1k | Resistor_SMD:R_0603_1608Metric | R7, R10 |
| 2 | 22pF | Capacitor_SMD:C_0603_1608Metric | C5, C9 |
| 2 | 27 | Resistor_SMD:R_0603_1608Metric | R8, R9 |
| 2 | IS31FL3236A-QFLS2-TR | easyeda2kicad:QFN-44_L5.0-W5.0-P0.40-BL-EP | U1, U2 |
| 2 | SW_Push | MX_Hotswap:MX-Hotswap-1.75U | SW23, SW24 |
| 2 | TS-1187A-B-A-B | Button_Switch_SMD:SW_SPST_SKQG_WithStem | BTN1, BTN2 |
| 1 | 1 | Resistor_SMD:R_0603_1608Metric | R11 |
| 1 | 12MHz | Crystal:Crystal_SMD_3225-4Pin_3.2x2.5mm | Y1 |
| 1 | 4.7uF | Capacitor_SMD:C_0805_2012Metric | C22 |
| 1 | 781710004 | Connector_Molex:Molex_Pico-EZmate_78171-0004_1x04-1MP_P1.20mm_Vertical | J1 |
| 1 | RP2040 | Package_DFN_QFN:QFN-56-1EP_7x7mm_P0.4mm_EP3.2x3.2mm_ThermalVias | U4 |
| 1 | SW_Push | MX_Hotswap:MX-Hotswap-2.75U-ReversedStabilizers | SW38 |
| 1 | SW_Push | MX_Hotswap:MX-Hotswap-2.25U-ReversedStabilizers | SW39 |
| 1 | TPS2051CDBV | Package_TO_SOT_SMD:SOT-23-5 | U6 |
| 1 | W25Q32JVUUIQ | Package_SON:Winbond_USON-8-2EP_3x4mm_P0.8mm_EP0.2x0.8mm | U5 |
| 1 | XC6206P332MR | Package_TO_SOT_SMD:SOT-23-3 | U3 |
Questions
How big is the Nehan42 PCB?
It measures 227.5 × 75.2 mm and has 4 copper layers, 1.6 mm thick.
What parts does the Nehan42 use?
183 parts, built around the RP2040, IS31FL3236A-QFLS2-TR, W25Q32JVUUIQ and TPS2051CDBVR. 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 Nehan42 KiCad files?
From the skeletonkbd/Nehan repository on GitHub, at the commit this page was made from: the board is Nehan42 PCB/Nehan42.kicad_pcb and its schematic Nehan42 PCB/Nehan42.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Nehan42 design in my own project?
Its repository publishes it under the CERN-OHL-S-2.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
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