DE1064102B - Transistor with partially falling characteristics - Google Patents

Description

GERMAN

^ ¹ ** - '■■■■■ "* ^

For electronic switching and counting purposes as well as in pulse technology, components are used that have a characteristic with a high-resistance and a low-resistance part as possible. Between These two parts are expediently an unstable area (falling characteristic), so that the both working states "off" and "on" become clear and the component through brief signals can be transferred from one to the other working state. In semiconductor technology so far for these purposes the tip transistor, the double base diode and the combination of an npn- with one pnp transistor used. However, some of these components have considerable disadvantages.

Therefore, the Hauptpatentaiimeldung hit a new ¹ S semiconductor device, a Trarsistor with partially falling characteristic for switching with short jump times and with flächenha: ten pn junctions at the emitter and collector to the article in which a stream of Mehrheitsladunjsträgern before the emitter potential uni produced by the injection of minority charge carriers at the emitter is increased. The main patent application is characterized in that the current from the majority charge carriers is more than ten times the saturation current ^a 5 of the collector, but is equal to the strand flowing in the flow state, and that the majority charge carrier current from the collector itself or from one directly adjacent to the collector is at least approximately A non-blocking auxiliary electrode lying at collector potential flows to the base electrode, so that between the emiter and the collector there is an electrical tensile field which accelerates the minority charge carriers in the direction from the emitter to the collector. The shape of the characteristic curve and the increased switching speed are thus brought about at the same time by the basic auxiliary current emanating from a suitable control unit. By avoiding this auxiliary current, the electrical properties of the switching transistor can be influenced, namely in the sense of a shortening of the jump times and a steepening of the negative part of the characteristic curve when the base current increases.

The aim of the additional invention? now consists in the transistor with short jump times, which is protected in the main patent application, has been replaced of the above-mentioned semiconductor components for the purposes of electronic switching, counting and pulse technology to use. The use of the switching transistor according to the main patent application offers im the following advantages:

Compared to the peak transistor, there is an increased mechanical and electrical stability, which is particularly important for high-quality counting devices with a partly falling transistor
Characteristic

Addendum to patent application, D21198 VIIIc / 21g
(Interpretation document 1 060 498)

Applicant:

German Federal Post Office,

represented by the President

the Central Telecommunications Office,

Darmstadt, Rheinstr. 110

Dr. phil. Helmut Salow, Darmstadt,
and Dipl.-Phys. Alfons Hahnlein,
Nieder Ramstadt (Kr. Darmstadt),
have been named as inventors

is important, as well as a more favorable ratio of blocking resistance to flow resistance and a larger one Power output.

Compared to the double base diode, a significantly lower signal requirement and an increased switching speed.

Compared to the npn-pnp combination, much less effort, since only one component is used instead of two transistors, and increased switching speeds when compared with normal low-frequency sheet transistors (f _ca <1 MHz); the use of special high-frequency transistors would mean an even greater effort.

When using the switching transistor according to the main patent application for the purpose of electronic Switching, counting and pulse technology are used to make use of other favorable properties. The technical The cost of a switching transistor is relatively low. It will be the one requested at the beginning Characteristic curve achieved with a component that is only slightly different in its structure from that of a normal 3-layer junction transistor differs. In addition, very short switching times are achieved with a Base thickness that corresponds to that of a normal low-frequency junction transistor, i.e. the is easy to achieve in terms of production technology.

909 609/302

Claims (5)

According to the additional invention, the switching transistor is used with short jump times as an electronic switch, as a pulse or frequency counter or generator in such a way that a control signal reverses the switching transistor from an operating point with a high current to an operating point with a low current or vice versa. For the purpose of the electronic switching of circuits, the switching transistor in the bistable tilted position experiences a change in resistance of more than 1 Ω to 20 Ω and less by means of a brief signal. The change in the working state can be used to close or open a circuit. It is important that the switching transistor achieves a blocking resistance to flow resistance ratio of 105: 1 and that powers of more than 100 mW can be delivered. The change in the working state can also be used to display short-term processes, such as B. for counting pulse trains. The registration of pulse trains can either take place according to the principle of the counting chain (ring counter), in which one of the stages carries current and the number of pulses received is read off at the position of the current carrying stage, or the coaster principle can be used, whereby from stage to stage only every 2nd, 4th ... 8th etc. pulse is passed on. In each pulse you get by with only one switching transistor per stage, and as a result of the very short switching time, pulse repetition frequencies of more than 1 MHz can be reliably processed without having to resort to special high-frequency transistors or peak transistors. The use of the switching transistor in the unstable range (astable tilting position) makes it possible to generate oscillations of more than 10 MHz. The form of the vibrations is given by the choice of the external switching means. The utilization of the high switching speed of the switching transistor finally makes it possible to produce pulses with a rise time of less than 2 · 10 -7 seconds in the monostable tilted position. Patent claims: 1. Transistor with partially falling characteristics for switching with short jump times after Patent application D 21198 VIII c / 21 g, characterized in that this is an electronic Switch is used as a pulse or frequency selector or generator in such a way that a control signal the switching transistor from an operating point with a high current to an operating point low current or vice versa. 2. Switching transistor according to claim 1, characterized in that the switching transistor in the bistable tilting position is used to open and close electrical circuits. 3. Switching transistor according to claim 1, characterized in that in a counting chain (ring counter) One switching transistor in the bistable tilt position is used per stage. 4. Switching Trarsistor according to claim 1, characterized in that in a step-down circuit only one switching transistor per stage is used in a bistable tilted position. 5. Switching traisistor preferably according to claim 1, characterized in that in one Schwingungssclaltung a switching transistor in the astable Kipphge is used. © 909 609/302 8.59