Circuit arrangement for selectively driving one or a number of power field-effect transistors in switching mode with potential isolation

摘要

The circuit arrangement for selectively driving one or a number of power field-effect transistors in switching mode with potential isolation by means of transformers brings improvement with respect to noise sensitivity, frequency range, power loss and space requirement. These are achieved with the aid of a centrally generated auxiliary voltage, the transmission of which is controlled by an electronic switch (7) controlled by the respective input signal (e1...en). The lack of sensitivity to electromagnetic interference is achieved by means of a low-resistance load resistor (12) between gate (G) and source (S) of the field-effect transistor (13). The resistor (12) also results in a rapid turn-off of the field-effect transistor (13), as a result of which the power loss of the transistor (13) is low. This is of significance particularly in the case of high frequencies. <IMAGE>