The paper presents the procedure for organizing the study of technical condition control in modern radio-electronic equipment, which is made on the element base of the fourth and fifth generations. The complex use of several methods of performance control is shown in digital standard replacement elements containing microcontrollers and calculated values of the output variables of the generalized module that correspond to real physical objects and could be used in the mathematical model of a digital standard replacement element. To reduce the number of test points in the diagnosis of digital standard replacement elements, as a source of diagnostic information used the parameters of the energy-dynamic process that occur in the power bus of digital elements when they switch from one logical state to another. This makes it possible to reduce the number of control points to one (power bus), while obtaining diagnostic information about technical condition of each logical element.The study is divided into four stages, which include: - analysis of the internal structure and allocation of subsystems in a typical replacement element; - decomposition of a typical replacement element and allocation of groups of variables; - synthesis of the structural and fu&nctional model of a digital typical replacement element; - simulation of the process of interaction of the developed mathematical model of the generalized microcontroller module with the external environment, analysis of the degree of adequacy of the& model to real physical objects. In summary, the structural-functional model of a digital typical replacement element, which provides for the integrated use of two sources of diagnostic information: output reactions and characteristics of the energy-&dynamic process in the power bus digital thesis.
