After bring-up and debugging, engineers execute the automation code to collect data across the full range of inputs and environmental conditions. This process is called process-voltage-temperature (PVT) characterization. The PVT automation code involves sequencing many individual actions (steps) in the correct order. A single measurement might include steps such as the following:
- Bringing the environmental condition to the required state
- Configuring the sources
- Setting the device into the specified mode by writing to its registers
- Turning on the sources
- Measuring the output of the device by reading the data from the instruments
Engineers must repeat each measurement by sweeping all the relevant control/input parameters included in the product specifications. This entire set of measurements has to be repeated for multiple devices to characterize the process variations. Engineers then must inspect the measurement data collected from all these sweeps for anomalies, identify their root causes, and correct them. The final set of good data is analyzed statistically to derive the product’s specifications, which are included in the data sheet.
This elaborate process must be automated as much as possible to reduce time and effort. By standardizing on an open and scalable automated infrastructure, engineers in the lab can focus on high-value validation tasks and minimize the time they spend on software development and debugging.
If the instrument references are shared between the debugging tools and the automation environment, then the automation engineer can move between the two environments in a seamless and efficient manner during automation code development. Data collection can last for many hours or even days. If the data does not look right at any time, engineers must pause stop the process to examine and fix the debugging tool and then resume the process without missing a beat.
Figure 4. Challenges and Solutions for Software Deployment in Lab Stations