Lexicon

Backdriving is a digital in-circuit test procedure for the functional isolation of digital components in the circuitry of a module. The method is also known as node forcing. Here, individual components or individual functional units of a digital component are subjected to a functional test on the module. When the supply voltage is switched on, the signals of the logically preceding components are located at the inputs of the DUT. The required signal states at the inputs of the tested device are forced by overwriting the randomly applied signals with defined test signals. This means that the respective outputs of the preceding devices are drawn to the required level by applying a sufficiently high current. It is important to monitor the required relatively high currents and, if necessary, to limit them in such a way that premature damage to the exaggerated output pin can be reliably ruled out. The safest and most reliable method for doing so is real-time performance monitoring of the digital drivers used in the test system, as it is realized with the hybrid pins of the Digitaltest Systems.