Purpose : Automatically detect, parse, and visualize electrical waveforms (VGE, VCE, ICE, POW) recorded during semiconductor testing company 'SPEA (https://www.spea.com/en/)' when a device is classified as FAIL.
In a high‑volume wafer or packaged‑device test line, every failed DUT (Device Under Test) produces raw text files that contain time‑series measurements such as gate‑emitter voltage (VGE), collector‑emitter voltage (VCE), collector current (ICE), and instantaneous power (POW). These measurements are stored inside a dedicated failure repository (e.g. C:\!FAIL_WFM).
This project continuously watches that repository, discovers newly created DUT folders, extracts the numeric vectors, and renders publication‑quality waveform images—one for the high‑side switch and one for the low‑side switch—so that process engineers and researchers can quickly inspect abnormal behaviour.
Although the code targets an industrial environment, it is intentionally lightweight and self‑contained so that university laboratories can reproduce the workflow on a standard Windows PC.
| FILE NAME | 378001X000JR590181_AC_RBSOA1_Low_Side |
|---|---|
| Plot Image |  |
| Feature | Description |
|---|---|
| Real‑time monitoring | Uses watchdog.Observer to detect freshly created test folders without polling. |
| Recursive discovery | Performs a depth‑first search to locate any directory that contains the expected *.txt waveform files. |
| Automated plot naming | Derives a descriptive JPEG filename (<BARCODE>_AC_<TEST>_<High or Low>_Side.jpg) from the directory hierarchy. |
| Dynamic offset plotting | When the folder name includes _SC (short‑circuit test), each waveform is vertically shifted just enough to avoid overlap, maximising readability. |
| Flexible scaling | Physical units per division (e.g. 10 V/div, 200 A/div) are automatically annotated in the legend. |
| Zero external dependencies | Requires only numpy, matplotlib, and watchdog. No proprietary libraries or test‑station software. |
- Folder Detection –
ObservertriggersNewDirectoryHandler.on_createdwhenever a new directory appears. - Debounce – The handler waits 3 seconds to ensure all text files are fully written.
- DFS Search – Recursively scans sub‑folders until it finds a set of waveform files.
- Data Loading – Preprocess each data.(Min-Max Scaling)
- Plot Naming – Parses the directory structure, looks up the test type, and returns a barcode‑based JPEG filename.
- Plotting –
- Normalises each channel according to
scale_map. - Applies either fixed (8 div) or dynamic offsets.
- Adds legends and unit annotations.
- Saves JPEG image at the source folder.
- Normalises each channel according to
All programs, source codes, and input output data belong to the SPEA company's assets. Distributed under the MIT License.
- The data used in the semiconductor test cannot be provided due to SPEA's security.
- Open‑source libraries: NumPy, Matplotlib, Watchdog.