Abstract: In a highly integrated circuit the semiconductor chip (8) is fastened on a substrate (17) which projects on all sides only a few millimeters beyond the semiconductor chip (8). For Full dynamic testing of the circuit before insertion, connections are provided which are arranged outside the projecting substrate edge (23) with a sufficiently large grid spacing.In a first embodiment (FIG. 2D) "lost" test connections (5) are used which are separated after testing.In a second embodiment (FIG. 3E), contact areas in the form of bumps (21) are used for testing which are arranged on the underside of the through-holes (18) lying in the chip mounting area.In this manner it is possible to realize a circuit with greatly reduced space requirement, which at the same time can be fully tested dynamically before insertion.