Changes

To make this test possible, DAVE Embedded Systems designed an ad hoc smart bench power supply denoted as PPSU. PPSU is used to power the DUT, which is the electronic device under test. You can think of PPSU as a programmable power waveform generator that is also able to verify the health status of the DUT. PPSU can generate an arbitrary supply voltage that exhibits purposely anomalies such as glitches of different duration and non-monotonic ramps. A robust product is expected to be resilient against these stressing conditions. This means that it the either one of the following conditions occur: * the DUT is supposed not to be affected at all or and continues to perform properly a warm reboot cycle operate regularly * if it is inevitable that a hardware reset is triggered, the DUT performs a warm reboot cycle and eventually returns to regular operating. Of course, the expected behavior depends strongly depends on the nature and severity of injected anomalies. After the anomaly is injected, PPSU verifies whether the DUT is operating properly or not and logs the test result. PPSU can also be programmed to run the test cycle repeatedly for the desired number of iterationsand optionally to stop if the test fails.

Combining several test waveforms of different types (1) and running these test over the entire DUT's operating temperature range allow to achieve good confidence that the product's PSU will not fail in the field because of "misbehaving" power suppliessupply. Furthermore, these tests are extremely useful to detect hardware design errors or more subtle situations like the one described in [https://www.st.com/resource/en/application_note/an5861-stpmic1-auto-turnon-stmicroelectronics.pdf this application note] by ST Microelectronicsas well. Thank to the use of PPSU, during the qualification of the [[ETRA SBC/General Information/Block Diagram and Features|ETRA Single Board Computer]], we were able to spot the issue illustrated in the this application note before its publicationSTM released it publicly.