Steuerbare Halbleiterschalteinrichtung mit integrierter Strombegrenzung und Übertemperaturabschaltung

摘要

A controllable semiconductor switching device having integrated overload protection of a load current path, including a switching section in the load current path and a multiplicity of main switching cells acting in parallel and having load-side terminals and non-load-side terminals including control terminals. The control terminals of the main switching cells are directly connected in a highly conducting manner among one another. A multiplicity of auxiliary switching cells are provided which carry a part of a total load current in parallel with the main switching cells in order to achieve an overload protection, and having load-side terminals and non-load-side terminals. The number of auxiliary switching cells are less than the number of main switching cells. The main switching cells and the auxiliary switching cells form the switching section. The load-side terminals of the main and auxiliary switching cells are directly connected in a highly conducting manner among and to one another, as are the non-load-side switching terminals. A second semiconductor switch has a switching section connected between the non-load-side switching terminals of the main switching cells. An element for measuring chip temperature is coupled to act on the second semiconductor switch with increasing chip temperature for turning the second semiconductor switch on. The element is disposed in the vicinity of the auxiliary switching cells at a periphery of a chip area covered by the main switching cells. At least one of the construction and a control variable of the auxiliary switching cells respectively differs from at least one of the construction and a control variable of the main switching cells in a manner such that specific current loading and specific power loss development of the auxiliary switching cells is essentially equally as great as that of the main switching cells with switching drive of the device and a load current below the overload limit. The specific current loading and the specific power loss development of the auxiliary switching cells increasingly exceeds monotonically that of the main switching cells with switching drive of the device and constant load current increase up to the overload limit.