Abstract: A ESD protective device is proposed, including a vertical bipolar transistor connected as a diode, in which the contacting of the collector layer is designed highly resistive. The arrangement, while having a space-saving construction, has an increased snap-back voltage.

Abstract: An ESD protection device encompassing a vertical bipolar transistor that is connected as a diode and has an additional displaced base area. The assemblage has a space-saving configuration and a decreased difference between snapback voltage and breakdown voltage.

Abstract: An ESD protective transistor comprises a heavily doped p-type base region which is arranged in a lightly doped p-well and which is provided with a first terminal. Furthermore, a heavily doped n-type emitter region is arranged in the lightly doped p-well. A heavily doped n-type collector region is separated from the lightly doped p-well through a lightly doped n-type region and is provided with a second terminal. The heavily doped n-type emitter region is not short-circuited with the heavily doped base region viy a common electrode and is of floating design. The doping types of the respective regions may be reversed.

Abstract: A light sensor having increased sensitivity and improved reaction speed includes a phototransistor and a source-follower transistor as an impedance converter for a potential of a main electrode of the phototransistor, and a second transistor as a feedback element between the second main electrode of the phototransistor and its control electrode.

Abstract: An ESD protection device is proposed, encompassing a vertical bipolar transistor that is connected as a diode and has an additional displaced base area. The assemblage according to the present invention has a space-saving configuration and a difference between snapback voltage and breakdown voltage that is decreased as compared to known assemblages.