Safely backdriving low voltage devices at in-circuit test

Effective in-circuit digital testing sometimes forces upstream devices to an opposite logic level with large currents during the test. Safely "backdriving" has been a challenge for in-circuit digital testing since its introduction two decades ago. A widely used approach has been to limit the duration of the backdrive current based on physical device parameters and failure mechanisms. This predictive method has recently been updated based on new research using modern low voltage (LV) logic families