4 layers230.7 × 97.8 mm
4 layers242.9 × 76.2 mm
Toprevan prototype
calvin-mcd/toprevan1EC pcb for minivan keyboards
- Size
- 242.9 × 76.2 mm
- Copper layers
- 4
- Thickness
- 1.59 mm
- Parts
- 122
- Nets
- 64
- Pads
- 530
- Tracks, vias
- 822, 415
- Pours
- 3
- Routed
- Yes
- KiCad
- KiCad 8.0 (file 20240108)
- Created
- 13 May 2024
- Updated
- 30 May 2025
Overview
Toprevan prototype is an open-source printed circuit board by calvin-mcd, from the calvin-mcd/toprevan repository on GitHub. It is a 4-layer board of 242.9 × 76.2 mm with 122 parts on 64 nets, routed with 822 tracks and 415 vias.
It is built around the OPA350UA, 74HC4051 and PRTR5V0U2X. Its parts include 24 resistors, 13 capacitors, 5 ICs, 4 connectors and 1 diode. It belongs with the RP2040 and STM32 boards of this library.
Main components
3
OPA350UA
SOIC-8-55℃~+150℃ 1 10pA 10pA 2.7V~5.5V 22V/us 38MHz 40mA 4uV/℃ 5.2mA 500uV 7nV/√Hz@10kHz 90dB Built-in compensation Rail-to-Rail Input, Rail-to-Rail Output SOIC-8 Operational Amplifier ROHSTexas InstrumentsPrecision Op Amps
74HC4051
SOP-16-40℃~+85℃ 1 170MHz 28ns 29ns 3V~9V 5ns 5pF 80Ω 8:1 SOP-16 Analog Switches, Multiplexers ROHSWuxi I-core ElecAnalog Switches, Multiplexers
PRTR5V0U2X
SOT-143-55℃~+125℃ 0.3pF、0.8pF 100W 10V、15V 5V 6.5V 6A 80nA ESD IEC 61000-4-2、IEC 61000-4-5、IEC 61000-4-4 Three channels Unidirectional SOT-143 ESD and Surge Protection (TVS/ESD) ROHSTECH PUBLICESD And Surge Protection (TVS/ESD)
README
README.mdtoprevan
The toprevan is a EC (topre) pcb for trashman's minivan keyboad. The pcb supports the minisub layout with both the 625U spacebar and the split 275U, 225U spacebars. The pcb has some of the traymout holes of the original minivan pcb but topre housings (and potentially some domes) need cutting to make that work.
Each layout requires its own respective plate. Various plate files can be found in the production folder. But since there are many different plate styles for the various cases out there, beware that plates could not have been tested beforehand.
VERSIONS: In the production folder you will find both the prototype production files and the revision files (as well as various plate files). Please be aware when ordering pcbs of their differences and what aspects have not been confirmed to work yet.
- The prototype is sporting a standard usb port which limits case compatibility a bit but using o-rings like on the travaulta should mitigate that in a bunch of cases. The rgb breakout has not been tested. Otherwise the pcb is fully working.
- The revision is using another USB port for more compatibility. It also sports all of the traymount holes. The rgb breakout has still not been tested. The revision has not been prototyped yet.
Layout
Firmware
The basic EC firmware is ready to go for qmk/vial and the source code is provided for tweaking any settings.
petejohanson has also provided zmk support for the toprevan:
https://github.com/petejohanson/toprevan-zmk-module
https://github.com/petejohanson/toprevan-zmk-config
Plates & Hardware
Plate files are available for OEM (original and deskey housings), for each respective bottom row choice, and for the original plate, Hull and Embrace cases.
Furthermore, you will need 22x 10mm M2 screws and M2 nuts to assemble the pcb. O-rings might help aligning the pcb and usb port in some cases, but is not required.
Disclaimer
Please note that this project is a work in progress with no guarantees of a working outcome. No-one involved in this project is responsible for any usage issues that may arise. Order at your own risk. Support will not be provided but pull requests will be reviewed and possibly accepted.
License
Shield: 
This work is licensed under a
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Credits
big thanks to petejohanson for feedback and help!
Furthermore, many thanks for feedback, help, references go to Sporkus, Cipulot#8455 & matthewdias#2671.
Any questions, contact Calvin0563 on Discord.
Parts
122| Qty | Value | Footprint | References |
|---|---|---|---|
| 46 | Topre | cipulot_parts:ecs_pad_1U_no_ring | SW_EC1, SW_EC2, SW_EC10, SW_EC11, SW_EC12, SW_EC13, SW_EC14, SW_EC15, SW_EC16, SW_EC17, SW_EC18, SW_EC19, SW_EC20, SW_EC21, SW_EC22, SW_EC23 +30 |
| 22 | MountingHole | cipulot_parts:HOLE_M2 | H1, H2, H3, H10, H11, H12, H13, H14, H15, H16, H17, H18, H19, H20, H21, H22 +6 |
| 14 | 100k | Resistor_SMD:R_0402_1005Metric | R2, R12, R13, R14, R15, R16, R17, R19, R20, R21, R22, R23, R24, R25 |
| 8 | 100n | Capacitor_SMD:C_0402_1005Metric | C6, C7, C8, C9, C10, C14, C16, C17 |
| 4 | 100 | Resistor_SMD:R_0402_1005Metric | R3, R4, R5, R6 |
| 3 | 10k | Resistor_SMD:R_0402_1005Metric | R9, R10, R11 |
| 3 | 1u | Capacitor_SMD:C_0402_1005Metric | C11, C12, C13 |
| 3 | LOGO | LOGO | G***, G***, G*** |
| 2 | 5k1 | Resistor_SMD:R_0402_1005Metric | R7, R8 |
| 2 | 74HC4051 | cipulot_parts:TSSOP16 | U4, U6 |
| 1 | 1k | Resistor_SMD:R_0402_1005Metric | R18 |
| 1 | 220p | Capacitor_SMD:C_0402_1005Metric | C15 |
| 1 | 4.7u | Capacitor_SMD:C_0402_1005Metric | C1 |
| 1 | 500mA | Fuse:Fuse_1206_3216Metric | F_USBC1 |
| 1 | 8 MHz | Crystal:Resonator_SMD_Murata_CSTxExxV-3Pin_3.0x1.1mm | Y1 |
| 1 | ARGB | Connector_PinHeader_2.54mm:PinHeader_1x03_P2.54mm_Vertical | J4 |
| 1 | BOOT0 | Connector_PinHeader_2.54mm:PinHeader_1x02_P2.54mm_Vertical | SW1 |
| 1 | Ext_Res | Resistor_SMD:R_0603_1608Metric_Pad0.98x0.95mm_HandSolder | JP1 |
| 1 | JST SH | Connector_JST:JST_SH_SM04B-SRSS-TB_1x04-1MP_P1.00mm_Horizontal | J1 |
| 1 | OPA350 | Package_SO:SOIC-8_3.9x4.9mm_P1.27mm | U5 |
| 1 | PRTR5V0U2X | Package_TO_SOT_SMD:SOT-143 | D1 |
| 1 | Pico EZmate | Connector_Molex:Molex_Pico-EZmate_78171-0004_1x04-1MP_P1.20mm_Vertical | J2 |
| 1 | STM32F401CBUx | Package_DFN_QFN:QFN-48-1EP_7x7mm_P0.5mm_EP5.6x5.6mm | U1 |
| 1 | USB_C_Receptacle_USB2.0 | Connector_USB:USB_C_Receptacle_HRO_TYPE-C-31-M-12 | J3 |
| 1 | XC6206PxxxMR | Package_TO_SOT_SMD:SOT-23 | U3 |
Questions
How big is the Toprevan prototype PCB?
It measures 242.9 × 76.2 mm and has 4 copper layers, 1.59 mm thick.
What parts does the Toprevan prototype use?
122 parts, built around the OPA350UA, 74HC4051 and PRTR5V0U2X. 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 Toprevan prototype KiCad files?
From the calvin-mcd/toprevan repository on GitHub, at the commit this page was made from: the board is Project/toprevan prototype.kicad_pcb and its schematic Project/analog.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Toprevan prototype design in my own project?
Its repository states no licence, so its author keeps all rights: ask calvin-mcd before reusing the design.
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