A switch-selectable digital frequency divider board designed in JLC EDA Pro.
This project is an improved and integrated open-source version based on the final coursework project for Tsinghua University's Basic Experiments for Electronic Circuits and Systems course.
This project was exported from the original Multicycle generator design. It provides related square-wave timing signals for waveform experiments, especially oscilloscope spirograph generation where stable integer frequency relationships produce repeatable visual patterns.
The board can be used as a standalone divider, or as the digital timing block in a larger analog signal-generation chain.
- Standard logic IC implementation.
- Counter/divider core based on SN74HC161N logic.
- Schmitt-trigger input conditioning.
- Header and selection interfaces for routing divider outputs.
- Useful for generating related clock signals for analog waveform experiments.
- JLC EDA Pro project export and Altium schematic/PCB export included.
The main logic devices used in this design include:
| Device | Role |
|---|---|
SN74HC161N |
Synchronous binary counter / divider core |
SN74HC00N |
NAND-gate support logic |
CD40106BE |
Schmitt-trigger conditioning |
The divider outputs are logic-level square waves. If a smoother waveform is required, use an appropriate low-pass filter after the selected divider output.
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Clock Input
Keep the input clock clean and well-conditioned. The CD40106BE Schmitt-trigger stage is useful when the board is driven from an analog oscillator or a signal with slower edges.
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Divider Selection
Select outputs according to the desired frequency relationship. For oscilloscope pattern generation, the ratio between channels usually matters more than absolute frequency accuracy.
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Output Loading
Treat the outputs as logic signals. Use high-impedance downstream stages or buffering if several circuits need to be connected at once.
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Filtering
Square-wave divider outputs contain strong harmonics. Use a downstream low-pass filter when the experiment needs a sine-like fundamental waveform.
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System Role
This board is closely related to the oscilloscope spirograph project. It provides the repeatable digital frequency relationships used before filtering, phase shifting, and summing.
| File | Description |
|---|---|
Altium_Multicycle_Frequency_Divider_2026-05-06.zip |
Altium export containing the schematic and PCB files. |
ProPrj_Multicycle_Frequency_Divider_2026-05-06.epro |
JLC EDA Pro project export. |
LICENSE |
MIT license. |
README.md |
Project introduction and design notes. |
Use ProPrj_Multicycle_Frequency_Divider_2026-05-06.epro to import the project back into JLC EDA Pro.
Use Altium_Multicycle_Frequency_Divider_2026-05-06.zip if you want to inspect or modify the exported Altium schematic and PCB files.
This repository contains the editable project exports. Manufacturing outputs such as Gerbers, BOM files, placement files, and assembly drawings are not included unless exported separately.
- Background article: https://mp.weixin.qq.com/s/7FQKxnxlLlElwnbqzJV7Ww
This project is released under the MIT License.