4 layers65 × 100 mm
4 layers65 × 100 mm
Audcalc
sinitsinmike/Audcalc2I'm happy with this, but its not 100% feature complete on the firmware side. Its really neat though, and I think you'll like it.
- Size
- 65 × 100 mm
- Copper layers
- 4
- Thickness
- 1.6 mm
- Parts
- 218
- Nets
- 222
- Pads
- 722
- Tracks, vias
- 2,116, 316
- Pours
- 1
- Routed
- Yes
- KiCad
- KiCad 8.0 (file 20240108)
- Created
- 25 Mar 2025
- Updated
- 25 Mar 2025
Overview
Audcalc is an open-source printed circuit board by sinitsinmike, from the sinitsinmike/Audcalc2 repository on GitHub, published under the MIT licence. It is a 4-layer board of 65 × 100 mm with 218 parts on 222 nets, routed with 2,116 tracks and 316 vias.
It is built around the RP2040, W25Q32JVSSIQ and HCPL-0631, with the MCP73831T-2ATI/OT-HXY, BAT54C and DMG2305UX-13 among its other parts. Its parts include 66 capacitors, 52 diodes, 35 resistors, 27 switches and 9 ICs. It belongs with the RP2040 boards of this library.
Main components
6
RP2040
LQFN-56(7x7)12bit 133MHz 30 LQFN-56(7x7) Microcontrollers (MCU/MPU/SOC) ROHSRaspberry PiMicrocontrollers (MCU/MPU/SOC)
W25Q32JVSSIQ
SOIC-8-208mil-40℃~+85℃ 100,000 cycles 133MHz 1uA 2.7V~3.6V 20 Years 32Mbit 3ms SPI SOIC-8-208mil NOR FLASH ROHSWinbondNOR FLASH
HCPL-0631
SOT-ALL-8-40℃~+85℃ 1.5V 15kV/us 2 3.75kV 4.5V~5.5V 5mA 75ns 75ns DC Output enable control、Open-collector output SOT-ALL-8 Logic Output OptoisolatorsBroadcom LimitedLogic Output Optoisolators
MCP73831T-2ATI/OT-HXY
SOT-23-5LBattery ManagementHXY MOSFET
BAT54C
SOT-231 Pair Common Cathode 200mA 2uA@25V 30V 600mA 800mV@100mA SOT-23 Schottky Diodes ROHSNexperiaSchottky DiodesDMG2305UX-13
SOT-23-55℃~+150℃ 1 P-Channel 1.4W 10.2nC@4.5V 20V 40mΩ@4.5V、52mΩ@2.5V 5A 77pF 808pF 85pF 900mV P-Channel SOT-23 MOSFETs ROHSDiodes IncorporatedMOSFETs
README
README.mdAudCalc
a pocket sized groovebox.
Note to folks stumbing across this repo.
I'm happy with this, but its not 100% feature complete on the firmware side. Its really neat though, and I think you'll like it.
v5 prototype
- RP2040
- 1/8in audio i/o
- onboard mic
- 104mm x 68mm x 14mm
The bom is contained within the Hardware kicad project, ready for assembly via jlcpcb. There are several additional items that must be sourced and handsoldered:
| part | count | mfg part number | link | notes |
|---|---|---|---|---|
| battery connector | 1 | jst s2b-ph-sm4-tb | https://octopart.com/s2b-ph-sm4-tb%28lf%29%28sn%29-jst-248913 | these are redibly available from aliexpress as well |
| midi / audio jacks | 4 | PJ-327C-4A | https://lcsc.com/product-detail/Audio-Connectors_Korean-Hroparts-Elec-PJ-327C-4A_C145813.html | I believe there is an equivalent CUI headphone jack. I'm using this cheaper version |
| pots | 2 | alps RK09K1130A5R | https://lcsc.com/product-detail/Variable-Resistors-Potentiometers_ALPSALPINE-RK09K1130A5R_C209779.html | |
| oled screen (128x32) | 1 | ssd1306 | https://www.aliexpress.com/item/4000842671330.html | I'm using the white / solderable version. |
| battery | 1 | lp-503562 | https://www.adafruit.com/product/258 | There are other cheaper sources for these. Confirm the correct polarity before using. |
| m2 4mm f-f standoff | 4 | https://www.aliexpress.com/item/1005002145042844.html | ||
| m2 6mm m-f standoff | 4 | https://www.aliexpress.com/item/1005002145042844.html | ||
| m2 3mm hex head bolt (black) | 8 | https://www.aliexpress.com/item/10000148429238.html |
Parts
218| Qty | Value | Footprint | References |
|---|---|---|---|
| 29 | 1u | MyLibrary:C_0402_1005Metric | C1, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20, C21, C22, C23, C24 +13 |
| 25 | spst_4_pin_internal | MyLibrary:ts1187 | SW1, SW2, SW10, SW11, SW12, SW13, SW14, SW15, SW16, SW17, SW18, SW19, SW20, SW21, SW22, SW23 +9 |
| 24 | D | RandomJunk:D_SOD-323F_less_silk | D27, D28, D29, D30, D31, D32, D33, D34, D35, D36, D37, D38, D39, D40, D41, D42 +8 |
| 20 | WS2812C-v1 | RandomJunk:ws2812b-2020-lightpipe | D10, D11, D12, D13, D14, D15, D16, D17, D18, D19, D20, D21, D22, D23, D24, D25 +4 |
| 14 | 100n | MyLibrary:C_0402_1005Metric | C2, C3, C5, C26, C27, C28, C29, C30, C31, C32, C34, C40, C60, C62 |
| 11 | 10u | MyLibrary:C_0402_1005Metric | C4, C36, C38, C42, C43, C46, C50, C55, C56, C57, C61 |
| 7 | SolderJumper_2_Bridged | Jumper:SolderJumper-2_P1.3mm_Bridged_Pad1.0x1.5mm | JP3, JP4, JP5, JP6, JP7, JP8, JP14 |
| 5 | 10k | MyLibrary:R_0402_1005Metric_nosilk | R3, R9, R14, R24, R30 |
| 4 | .47u | RandomJunk:C_0603_nosilk | C39, C44, C45, C47 |
| 4 | 1k | MyLibrary:R_0402_1005Metric_nosilk | R6, R7, R17, R31 |
| 4 | D_Zener | Diode_SMD:D_SOD-323F | D3, D4, D5, D26 |
| 4 | MountingHole | Mounting_Holes:MountingHole_2.2mm_M2 | H1, H2, H3, H4 |
| 3 | 100k | MyLibrary:R_0402_1005Metric_nosilk | R8, R18, R25 |
| 3 | 220 | MyLibrary:R_0402_1005Metric_nosilk | R10, R11, R21 |
| 3 | 33 | MyLibrary:R_0402_1005Metric_nosilk | R12, R34, R35 |
| 3 | 5.1k | MyLibrary:R_0402_1005Metric_nosilk | R19, R20, R23 |
| 2 | 100 | Resistor_SMD:R_0402_1005Metric | R32, R33 |
| 2 | 1m | MyLibrary:R_0402_1005Metric_nosilk | R27, R28 |
| 2 | 27.4 | MyLibrary:R_0402_1005Metric_nosilk | R1, R2 |
| 2 | 3.3k | MyLibrary:R_0402_1005Metric_nosilk | R4, R5 |
| 2 | 30p | MyLibrary:C_0402_1005Metric | C35, C37 |
| 2 | 330 | MyLibrary:R_0402_1005Metric_nosilk | R22, R26 |
| 2 | 47uf | Capacitors_SMD:C_1206 | C48, C49 |
| 2 | ME6211C | TO_SOT_Packages_SMD:SOT-23-5 | U9, U11 |
| 2 | Q_NMOS_GSD | TO_SOT_Packages_SMD:SOT-23 | Q3, Q4 |
| 2 | R_POT_US | Potentiometers:Potentiometer_Alps_RK09K_Horizontal | RV1, RV2 |
| 2 | SolderJumper_2_Open | Jumper:SolderJumper-2_P1.3mm_Open_RoundedPad1.0x1.5mm | JP1, JP2 |
| 2 | spst_4_pin_internal | MyLibrary:SKSCLDE010 | SW26, SW27 |
| 1 | 10 | MyLibrary:R_0402_1005Metric_nosilk | R13 |
| 1 | 100u | Capacitor_Tantalum_SMD:CP_EIA-3528-21_Kemet-B | C65 |
| 1 | 10n | MyLibrary:C_0402_1005Metric | C59 |
| 1 | 10u | Capacitors_Tantalum_SMD:CP_Tantalum_Case-A_EIA-3216-18_Reflow | C58 |
| 1 | 128x32OLED | MyLibrary:oled_ssd1306_14pin_91 | LCD1 |
| 1 | 2u2 | MyLibrary:C_0402_1005Metric | C66 |
| 1 | 330k | MyLibrary:R_0402_1005Metric_nosilk | R15 |
| 1 | 4.7k | MyLibrary:R_0402_1005Metric_nosilk | R16 |
| 1 | 750k | RandomJunk:C_0603_nosilk | R29 |
| 1 | AP3722AT_mic | MyLibrary:LGA-4 (3x3.8) | U4 |
| 1 | BAT54C | TO_SOT_Packages_SMD:SOT-23 | D1 |
| 1 | Conn_01x02_Female | Connector_PinHeader_2.54mm:PinHeader_1x02_P2.54mm_Vertical | J8 |
| 1 | Crystal_GND24 | Crystals:Crystal_SMD_3225-4pin_3.2x2.5mm | Y1 |
| 1 | DMG2305UX-13 | digikey-footprints:SOT-23-3 | Q1 |
| 1 | D_Schottky | Diodes_SMD:D_SMA | D53 |
| 1 | HCPL-0631 | Package_SO:SOIC-8_3.9x4.9mm_P1.27mm | U5 |
| 1 | LED | LEDs:LED_0603 | D54 |
| 1 | LEDGreen | LEDs:LED_0603 | D2 |
| 1 | LM4040DBZ-2.5 | Package_TO_SOT_SMD:SOT-23 | U7 |
| 1 | MCP73831T-2ATI_OT | TO_SOT_Packages_SMD:SOT-23-5 | U6 |
| 1 | Q_PMOS_GSD | TO_SOT_Packages_SMD:SOT-23 | Q2 |
| 1 | RP2040 | MCU_RaspberryPi_and_Boards:RP2040-QFN-56 | U2 |
| 1 | TLV320AIC3204 | Housings_DFN_QFN:QFN-32-1EP_5x5mm_Pitch0.5mm | U3 |
| 1 | USB_C_Receptacle_USB2.0 | RandomJunk:USB-C_SMD-TYPE-C-31-M-12 | J2 |
| 1 | W25Q32JVSS | Housings_SOIC:SOIJ-8_5.3x5.3mm_Pitch1.27mm | U1 |
| 1 | battery | Connectors_JST:JST_PH_S2B-PH-SM4-TB_02x2.00mm_Angled | J7 |
| 1 | headphone_out | RandomJunk:HRO-PJ-327C-A | J4 |
| 1 | line_in | RandomJunk:HRO-PJ-327C-A | J3 |
| 1 | midi_in | RandomJunk:HRO-PJ-327C-A | J5 |
| 1 | midi_out | RandomJunk:HRO-PJ-327C-A | J6 |
| 1 | picoprobe_debug | RandomJunk:pico debug header | J1 |
Questions
How big is the Audcalc PCB?
It measures 65 × 100 mm and has 4 copper layers, 1.6 mm thick.
What parts does the Audcalc use?
218 parts, built around the RP2040, W25Q32JVSSIQ, HCPL-0631 and MCP73831T-2ATI/OT-HXY. 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 Audcalc KiCad files?
From the sinitsinmike/Audcalc2 repository on GitHub, at the commit this page was made from: the board is Hardware/audcalc/audcalc.kicad_pcb and its schematic Hardware/audcalc/ButtonsLEDS.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Audcalc design in my own project?
Its repository publishes it under the MIT 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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