| 摘要 |
<p>A circuit arrangement for protecting an input of an integrated circuit (14) fed from a supply voltage source from overvoltages contains an input (26) which is connected to the input (12) of the integrated circuit to be protected. A four-layer diode (T1, T2) having two control terminals lies in parallel with the input (12) to be protected and a negative feedback resistor (R1) is connected in series with the four-layer diode. Connected to the one control terminal of the four-layer diode (T1, T2) is the control terminal of a controllable current drain element (T4) which is connected in parallel with the four-layer diode (T1, T2). For applying a reference voltage, the junction point of a series circuit comprising a diode (T3) and a constant current source (S) lying between the supply voltage and ground is connected to the other control terminal. <IMAGE></p> |
