ADM9240/ADM1021/ADM1024 test methodology

This paper deals with the methodology used in the test development of the ADM9240, ADM1021 and ADM1024 hardware monitoring devices. It will concentrate on the design for testability (DFT) features incorporated into the devices, which enable the competing goals of high quality levels and minimum test cost to be achieved. Many DFT features were implemented in these devices but this paper will concentrate on two in particular, the analogue to digital converter (ADC) test features and the digital core test features. Firstly we look at the application for the devices, and the subsequent customer requirements. We then examine the ADM1021 device in particular and highlight the testability problems with the part if a DFT approach was not taken. The details of the DFT approach taken, and the benefits of this approach will then be discussed. Lastly we will look at how the approach is being developed and refined for future products.