Schutzschaltung fur aktive bauelemente gegen uber- bzw. unterspannung

摘要

The invention relates to a protective circuit for protecting active components from over- or undervoltage. Said protective circuit consists of a limiting resistor (Ri) that is connected in series upstream of the input (E1) of the component to be protected. The protective circuit further comprises a respective protective diode (Di1; Di2) that is arranged in the direction of blockage between the junction (P3) of the limiting resistor (Ri) and the input (E1) of the component on the one hand and the power supply potentials (Vdd; Vss) on the other hand. A serial resistor (R1) and a respective reference diode (Di1; Di2) are mounted in series between the power supply potentials (Vdd; Vss). Said reference diode (D1; D2) is arranged in the direction of passage between the supply potential (Vdd; Vss) and the serial resistor (R1). The value of resistance of the serial resistor (R1) is substantially smaller than that of the limiting resistor (Ri). The protective diode (Di1; Di2) is connected to the junction (P1; P2) of the serial resistor (R1) and the reference diode (D1; D2) with its electrode facing away from the limiting resistor (Ri).