2 layers232 × 134 mm
2 layers100 × 100 mm
Fuji Synth
A41K/Fuji-SynthThe firmware can be found in /Firmware/Firmware.cpp
- Size
- 100 × 100 mm
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 59
- Nets
- 68
- Pads
- 209
- Tracks, vias
- 1,672, 80
- Routed
- Yes
- KiCad
- KiCad 10.0 (file 20260206)
- Created
- 19 Oct 2026
- Updated
- 24 Oct 2026
Overview
Fuji Synth is an open-source printed circuit board by A41K, from the A41K/Fuji-Synth repository on GitHub. It is a 2-layer board of 100 × 100 mm with 59 parts on 68 nets, routed with 1,672 tracks and 80 vias.
It is built around the MPR121QR2 and PCM5102APW. Its parts include 18 resistors, 12 capacitors, 5 switches, 3 ICs and 1 connector. It belongs with the audio and music boards and the RP2040 boards of this library.
Main components
2
MPR121QR2
QFN-20(3x3)-40℃~+85℃ 1.71V~3.6V 12 29uA 2kV 3uA Capacitive Touch QFN-20(3x3) Touch Sensors ROHSNXP SemiconductorsTouch Sensors
PCM5102APW
TSSOP-20-25℃~+85℃ 1.8V~3.3V 2 32 384kHz 500uA 50MHz Audio Decoder Digital filtering、Power-down mode I2S TSSOP-20 ADCs/DACs - Special Purpose ROHSTexas InstrumentsADCs/DACs - Special Purpose
README
README.mdFuji Synth
A smaller 12 pad touch synthesizer with
- 3 rotary encoders
- 2 buttons
- a 0.91 inch screen
- 2 Sliding potentiometers
PCB
Schematic
3d model
The firmware can be found in /Firmware/Firmware.cpp
Parts
59| Qty | Value | Footprint | References |
|---|---|---|---|
| 12 | 330R | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18 |
| 12 | TestPoint | Library:TouchPad_D12mm | TP1, TP2, TP3, TP4, TP5, TP6, TP7, TP8, TP9, TP10, TP11, TP12 |
| 9 | 100nF | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C2, C3, C6, C7, C8, C9, C10, C11, C12 |
| 4 | MountingHole | MountingHole:MountingHole_2.2mm_M2 | H1, H2, H3, H4 |
| 3 | RotaryEncoder_Switch | Rotary_Encoder:RotaryEncoder_Alps_EC12E-Switch_Vertical_H20mm | SW1, SW2, SW4 |
| 2 | 100R | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R1, R2 |
| 2 | 10k | Potentiometer_THT:Potentiometer_Bourns_PTA1543_Single_Slide | RV1, RV2 |
| 2 | 2.2uF | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C4, C5 |
| 2 | 4.7k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R3, R4 |
| 2 | SW_Push | Button_Switch_THT:SW_PUSH_6mm | SW3, SW5 |
| 1 | 10k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R5 |
| 1 | 10uF | Capacitor_SMD:C_0805_2012Metric_Pad1.18x1.45mm_HandSolder | C1 |
| 1 | 75k | Resistor_SMD:R_0805_2012Metric_Pad1.20x1.40mm_HandSolder | R6 |
| 1 | AudioJack3 | Connector_Audio:Jack_3.5mm_Lumberg_1503_02_Horizontal | J1 |
| 1 | ER_OLEDM0.91_1x-I2C | Display:ER_OLEDM0.91_1x-I2C | U2 |
| 1 | LOGO | LOGO | G*** |
| 1 | MPR121QR2 | Package_DFN_QFN:UQFN-20_3x3mm_P0.4mm | U3 |
| 1 | PCM5102A | Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm | U1 |
| 1 | RaspberryPi_Pico | Module:RaspberryPi_Pico_Common_THT | A1 |
Questions
How big is the Fuji Synth PCB?
It measures 100 × 100 mm and has 2 copper layers, 1.6 mm thick.
What parts does the Fuji Synth use?
59 parts, built around the MPR121QR2 and PCM5102APW. 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 Fuji Synth KiCad files?
From the A41K/Fuji-Synth repository on GitHub, at the commit this page was made from: the board is Fuji-Synth/Fuji-Synth.kicad_pcb and its schematic Fuji-Synth/Fuji-Synth.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Fuji Synth design in my own project?
Its repository states no licence, so its author keeps all rights: ask A41K before reusing the design.
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