2 layers65.6 × 32.6 mm JAC, the printed circuit board in 3D

JAC

Just A Clock.

Size: 65.6 × 32.6 mm
Copper layers: 2
Thickness: 0.8 mm
Parts: 23
Nets: 36
Pads: 108
Tracks, vias: 228, 62
Pours: 5
Routed: Yes
KiCad: KiCad 6 (file 20211014)
Created: 13 Jan 2024
Updated: 23 Feb 2025

Overview

JAC is an open-source printed circuit board by ieiao, from the ieiao/JAC repository on GitHub. It is a 2-layer board of 65.6 × 32.6 mm with 23 parts on 36 nets, routed with 228 tracks and 62 vias.

It is built around the ESP32-C3-WROOM-02-H4, RX-8025T and AO3401A. Its parts include 8 resistors, 4 capacitors, 4 ICs, 1 transistor and 1 connector. It belongs with the ESP32 and RISC-V boards of this library.

Main components

README

README.md

Just A Clock

How to compile

goto source directory

text

$ cd fw

compress web source file

text

$ cd spiffs_image
$ gzip -9 *
$ cd ..

build project

text

$ idf.py build

generate resources

text

$ # output is build/res/res.bin
$ ./tools/genres.sh

generate OTA file (optional)

text

$ # output is build/JAC_ota.bin
$ ./tools/genota.sh

flash

text

$ # resources and web archives must flash with app
$ python -m esptool --chip esp32c3 -b 460800 --before default_reset --after hard_reset write_flash --flash_mode dio --flash_size 4MB --flash_freq 80m 0x0 build/bootloader/bootloader.bin 0x8000 build/partition_table/partition-table.bin 0xd000 build/ota_data_initial.bin 0x90000 build/JAC.bin 0x380000 build/storage.bin 0x10000 build/res/res.bin

You can use the file generated in step 5 to update the firmware through OTA.

Parts

Qty	Value	Footprint	References
4	10K	Resistor_SMD:R_0603_1608Metric	R1, R2, R3, R4
4	Jumper_2_Open	Resistor_SMD:R_0402_1005Metric	JP1, JP2, JP3, JP4
2	4.7K	Resistor_SMD:R_0603_1608Metric	R7, R8
2	5.1K	Resistor_SMD:R_0603_1608Metric	R5, R6
1	0.1u	Capacitor_SMD:C_0603_1608Metric	C1
1	0.1uF	Capacitor_SMD:C_0603_1608Metric	C3
1	10uF	Capacitor_SMD:C_0805_2012Metric	C4
1	1uF	Capacitor_SMD:C_0603_1608Metric	C2
1	4056M	JAC:4056M	U2
1	AO3401A	Package_TO_SOT_SMD:SOT-23	Q1
1	BT0	Button_Switch_SMD:SW_Push_SPST_NO_Alps_SKRK	SW1
1	EPDM	JAC:EPDM	U1
1	ESP32-C3-WROOM-02	JAC:ESP32-C3-WROOM-02	U4
1	RX-8025T	Package_SO:SO-14_5.3x10.2mm_P1.27mm	U3
1	USB_C_Receptacle_USB2.0	Joke:TYPE-C-VERT	J1

Questions

How big is the JAC PCB?

It measures 65.6 × 32.6 mm and has 2 copper layers, 0.8 mm thick.

What parts does the JAC use?

23 parts, built around the ESP32-C3-WROOM-02-H4, RX-8025T and AO3401A. 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 JAC KiCad files?

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

Can I use the JAC design in my own project?

Its repository states no licence, so its author keeps all rights: ask ieiao before reusing the design.

Category and platform

ESP32 RISC-V

Project files

Show this board on your page

A live frame, for any web page

<iframe src="https://pcbkit.io/embed/boards/ieiao-jac" title="JAC in PCBKit" width="100%" height="480" style="border:0;border-radius:12px" allow="fullscreen" loading="lazy"></iframe>

A picture

<img src="https://pcbkit.io/embed/boards/ieiao-jac.jpg" alt="JAC" width="1200" height="900">

A picture that opens the board, for a README

[![JAC](https://pcbkit.io/embed/boards/ieiao-jac.jpg?size=s)](https://pcbkit.io/boards/ieiao-jac)

Source

Repository: ieiao/JAC
Board file: hw/JAC.kicad_pcb
Commit: 319c8f5
Licence: Not stated

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