DE1084760B - Switching arrangement controllable by a light beam with a thread semiconductor arrangement, for example a double base diode - Google Patents

Description

From the reference "A two-state light activated circuit element using germanium" from British J. Appl. Phys., 6 (1955), p. 172/173, a semiconductor device for switching purposes has become known, which consists of a Double base diode and a homogeneous semiconductor resistor connected in series. The current-voltage characteristic this arrangement has an unstable region (i.e. a region of falling characteristic), which is arranged between two stable areas. The arrangement can be of the one stable state can be switched to the other stable state by placing light alternately on the double base diode or drops on the homogeneous semiconductor resistor.

The present invention deals with a controllable by a light beam arrangement for switching or for regulating with a thread semiconductor, z. B. a double base diode which, in contrast to the known arrangement, does not require any additional semiconductor resistance. The arrangement according to the invention can be expanded into a switching arrangement which can be controlled by a light beam and has N stable operating points. N is any whole and positive number.

In the switching arrangement according to the invention, which can be controlled by a light beam, with a thread semiconductor (e.g. a double base diode or a double base transistor) with an η-conducting (or p-conducting) Semiconductor body and two - preferably arranged on two opposite surfaces - free of barrier layers contacted base electrodes, which - if necessary via a limiting resistor - to a DC voltage source lie, as well as with at least one other positive (or negative) against the negative (or positive) base electrode biased emitter electrode, which is above (or below) a certain Bias voltage minority carriers are injected into the semiconductor body of the thread semiconductor, whereby the emitter electrode Connected to the positive (or negative) pole of a DC voltage source via an ohmic resistor is, according to the invention, the resistance and the voltage source are dimensioned such that the characteristic of the resistance, the characteristic curve of the unexposed one assigned to the operating voltage between the base electrodes Thread semiconductor arrangement intersects at an operating point in the stable blocking range of this characteristic curve, while they only have the characteristic curve of the exposed thread semiconductor arrangement belonging to the same operating voltage meets at an operating point in the pass band.

For the dimensioning of the voltage source and the resistance are according to the further invention the following two options are provided:

A. The resistance and the voltage source are dimensioned in such a way that the characteristic curve of the resistance that of the operating voltage between the base electrodes

By a ray of light

controllable switching arrangement

with a thread semiconductor arrangement,

for example a double base diode

Applicant:

Siemens & Halske Aktiengesellschaft,

Berlin and Munich,
Munich 2, Wittelsbacherplatz 2

Dr. Heinz Dorendorf, Munich,
has been named as the inventor

assigned characteristic curve of the unexposed thread semiconductor arrangement only in a single operating point, and although it is in the stable blocking range of this characteristic, it intersects the one belonging to the same operating voltage Characteristic of the exposed thread semiconductor arrangement only meets at one operating point in the pass band.

B. The resistance and the voltage source are dimensioned such that the characteristic curve of the resistance to the Operating voltage between the base electrodes associated characteristic curve of the unexposed thread semiconductor arrangement in one working point in the stable blocking range and in another stable working point in The flow range of this characteristic line intersects while it intersects the characteristic line belonging to the same operating voltage exposed thread semiconductor arrangement meets only in the flow area. The emitter electrode is over a Resistance connected to the positive (or negative) pole of a DC voltage source, the resistance and the voltage source are dimensioned in such a way that the behavior of the characteristic curves just described occurs.

Fig. 1 a shows the circuit of an arrangement according to the invention using a double base diode with an η-conductive semiconductor body H, z. B. made of silicon or germanium, and the two base electrodes B ₁ , B ₂ attached without a barrier layer, between which there is a direct voltage U (B ₁ = negative, B ₂ - positive base electrode). In the present example, D is an emitter electrode made of acceptor material alloyed in the semiconductor body H of the double base diode, which forms a pn junction with the semiconductor body H and injects minority carriers into the semiconductor body H of the diode when the bias voltage is sufficiently high. The electrode D is connected via a resistor R to the positive pole of a direct voltage source V, the negative pole of which is connected to B ₁ . If necessary, a limiting resistor i? & Can also be provided in the circuit between the base electrodes and the DC voltage source U.

009 549/297

Fig. Ib shows some characteristic curves U _D = / (In) for U > 0 exposure a steady sliding over from the flow state

with the operating voltage U as a parameter. Here in is in the off state.

. the current passing through the electrode D and Un the span but the condition A, b) can also be fulfilled if

voltage between electrode D and electrode B ₁ . . man ■

U becomes smaller, the characteristics 5 (DUN \ move ^{unbelit; htet}

downward. In the falling "area of the characteristic, the & 9Ίπ <- I " qJZT J _

Slope at the top between the restricted area and the flow area ^D ~

the biggest. It is approximated by the derivative power. In this case it follows

dUp \ / gf / ^ unexposed

XO

given. The double base diode is initially unexposed, or

unexposed

din

I _D = 0

and the operating voltage U is fixed. The associated characteristic is shown as curve I with the peak ai in A, b ₂ ) R <
Fig. 1 c is drawn. By exposing the semiconductor 15
The body of the diode, especially between B ₁ and D, is here at the transition from the exposed to this area due to the photo effect of lower resistance, so that there was a transition characterizing voltage drop along H between B ₁ and B ₂ in the unexposed state - lines that go from the resistance line III both in the more or less flow area, depending on the intensity of the exposure, as well as in the blocked area, to the area between B ₂ and D are pressed together. Since D ao Since, however, the one corresponding to the unexposed state is always positively biased with respect to B ₁ , the characteristic curve I does not come to an intersection with the resistor diode in the flow direction. In the characteristic curve image, a straight line III acts in the flux area, so after Wegs it turns out as if the operating voltage U were lowered, the diode would move from the flux area into the exposure. The stable blocking range for a given operating voltage U. A flip-over process therefore only takes place with the characteristic curve II 25 belonging to the exposed double-base diode when the dimensioning rule A, b ₂ ) is selected.
therefore always lies below the characteristic curve I of unbeüch- To the greatest possible sensitivity of the Anordteten diode and has a similar profile to achieve such a voltage, it is V - of course under curve of the unexposed diode, a smaller compliance with A, a) - Choose as large as possible and R is assigned to operating voltage U. In general, do not make the larger than it is absolutely necessary due to the requirement characteristic of the exposed diode, the larger 30 A, b). When choosing the control the intensity of the exposure is. In the case of a certain measurement rule A, b ₂ ) for the resistance R , this is the intensity of the exposure.
designated course. If R and V are A, ie

The characteristic curve III, also drawn in FIG. 1 c, is selected according to regulations A, a) and A, b), so works

of the resistor R is as a function of the 35 the arrangement according to the invention in the unexposed

pressure Un = V - R · In given; it is therefore a straight line, stood at an operating point X ₁ in the stable blocking

whose inclination is given by tg <p ", = - R and the area. So the diode is blocked. With enough

the ordinate axis at the level of the voltage V snow intensity of a on the semiconductor body of the double base

det. According to the first measurement option, it should go between D and B _{1 of the} incident light beam

According to the invention, the characteristic curve I of the unexposed 40, the characteristic curve I in state II and the operating point X ₁

Double base diode only in one working point X ₁ , which in the working point X ₂ over. So the diode flips in

stable blocking area, ie to the left of the tip α _τ , lies, flow direction. After the exposure is removed

cut while the characteristic curve II of the exposed the original state again. The characteristic goes

Double base diode only in one working point X ₂ in the flow back into state I, over and the working point reverses

area, ie to the right of the tip «u. 45 back to the original location X ₁ . The diode

This requirement is met with certainty, so if you go back into the after the end of the exposure

V selects such that the lock state condition is over. This transition is a tilting

A a) / T £ \ unbeEchtet ^ γ y, tjj \ exposed process when the resistance R in accordance with the condi- ¹ O ⁰ = = o ISS supply A, is selected b _2). When the exposure is renewed, it is met again, and care is also taken that A, b) the 50 gets the same game. If the design pre-inclination angle <p _{m of} the resistance straight line III lowercase A is selected, a switching arrangement is obtained which is defined as the inclination angle ■ & that generated by the on the ordi- in exposure and in the darkened state (Γ / zrAxis) in the The amount of the locks selected in accordance with A, a) is.

Voltage V lying point P on the characteristic curve I ge. To understand the dimensioning option B.

laid tangent T. ■ 55 of the invention, reference is made to Fig. 1d. I and II mean

Condition A, b) is fulfilled when the characteristics Un = f (In) of the double base diode are used again

/ a TT unexposed ^ unexposed or in the exposed state for a

tg <p _m <(———] given operating voltage U. Now the characteristic

V 3 Id} ΐ _ΰ = ο line U _D = V - R-In of the resistor R (which again

chooses. 60 is denoted by III) the characteristic curve I of the unexposed

Since tg φ ΐα - - R _{, double base diode} follows in an operating point Y ₁ in the stable

/ QTJ _{D of the} restricted area, ie to the left of the tip αι, and in one

- R < [~ kj -j intersect another stable working point Y ₂ in the flow area.

D JiJ) ^ o (j _eil) while they show the characteristics of the exposed diode

or 65 should only meet at one working point Y ₃ in the flow area.

I 9 Uj) ^Voluntary i ^o r ^tet For this is the demand

'"Λ>. - =. Unexposed _{F. ITT} , exposed

i ϋΐη, IjJ = O B, a) (Un) _{Iü = zD} >V> (U _D ) _{Ii) = D}

One chooses the resistance R according to the design to be met. In addition, care must be taken

Rule A, bj, after removing the 70 one gets that B, b) the angle of inclination <p _U i of the resistance

1 UÖ4 / DU
5 6

Raden III is greater than the angle of inclination d- which remain through direction in the flow direction. A return to the on the ordinate (Ud axis) at the level of the initial state can be, for. B. achieve if the B, a) selected voltage V lying point P to the voltage source V off and on again.
Characteristic line I laid tangent T. With the combined arrangement described so far

To fulfill condition B, b) it is necessary that each switching element worked 5 voltages according to the invention the arrangement independent of the other. This independence is abolished if one according to a further development of the invention another

B, I) ₁ ) 22 <

is. However, the condition B, b _x ) is - in contrast to ohmic resistance R ₀ , which provides between that of the condition B, b) - not necessarily sufficient. With io JV switching elements and the common voltage fulfillment of the conditions B, a) and B, b) occurs next to source V, which supplies the bias voltage for the emitter electrodes stable operating points Y ₁ and Y ₂ on the characteristic electrodes D is connected in this way that he has another unstable working point L with the line I. Resistors R is in series. Such an arrangement

In the unexposed state, the arrangement in FIG. 2 operates with JV = 3 double base diodes for the case

the η-conducting semiconductor body of the diodes represented by the intersection point Y _{1 in the stable blocking region 15,}

defined state. The arrangement is therefore blocked. In Fig. 2 a, let A be a point at the output of the resistor

When exposed, the characteristic of the double base diode goes to R ₀ . The potential of this point over the

from curve I to curve II. The base electrode B ₁ migrates with the lower potential, ie

The operating point according to Y ₃ , the intersection of the characteristic voltage Va, then takes over when used

line II with the resistance straight line III, the role in the flow 20 of a common resistance R ₀ , which at

area lies. After removing the exposure, the previously described arrangements of the fixed moves

the working point along the resistance line III to voltage V came to: the characteristic of the resistances R

the stable working point Y ₂ on the characteristic curve I of the intersects the ordinate axis in the ÜO / Jß diagram in

unexposed diode, which is also in the flow area. the height Va- The voltage Va is according to Va = V - ^ o "Xd

The double base diode therefore remains conductive. To them again 25 by the voltage drop across the resistor R ₀

Bring into the restricted area, you can z. B. which is conditional and thus depends on the totality of JjJ der

Switch off voltage V briefly. Currents flowing through the electrodes D. Through this

In this case, too, the voltage V - a coupling between the JV parts used will of course be effected in compliance with rule B, a) - arrangements.

Choose as large as possible in order to achieve a high sensitivity. First, let the resistance R _{0 be} from zero to arbitrary

to achieve the arrangement. Any desired low-high values can be set and the voltage source V

According to the above, there are no limits to the value of R. dimensioned so that for a given operating voltage U

Rather, through practical considerations, these are all double base diodes of the arrangement in

given. It will be ensured that the cleared states are in the direction of flow at R _{0 = 0.}

Arrangement in the flow state heated as little as possible and 35 Then Va = V. By successively increasing R ₀

therefore the stable working point Y ₂ as far as possible, the potential Va of point A decreases monotonically

to the left on characteristic curve I. So one does not get R and thus also the potential of the emitter electrodes D.

make it much smaller than at a given voltage V would all double base diodes of the arrangement in

is necessary to make the two intersection points Y _x and Y _{2 of} all severity equal, they would have to, if Vj. a

to achieve with certainty. 40 falls below a certain critical value, at the same time

JV switching elements of the invention can be toggled into a reverse direction. In reality, it is not possible to achieve uniformity combined with JV stable working points. It will therefore switch. This is done by JV similar and in the one diode of the arrangement after the other in the blocking size of their switching elements toggle the same selected arrangements direction. This effect can always be achieved by successively using η-conducting (or p-conducting) semiconductor bodies with an enlargement of R ₀ , regardless of the type described so far, the resistance R of which either initially determines the resistances R of the arrangement only according to the dimensioning option A or only after are. The invention, however, selects the following two dimensioning options B, so that options for the behavior of the arrangements are switched on in parallel that each of the emitter electrodes D strives:

an equally large resistor R with the positive 50. First possibility: With an unexposed arrangement (or negative) pole of a common voltage, all double base diodes of the arrangement should be connected in blocking source V whose negative (or positive) pole are in the direction. During exposure, only a single diode - and the negative pole (or positive pole) of a second, between the one struck by a light beam - diode and the base electrodes B ₁ , B _{2 of} all thread used should be open, while the others are still in Blocking semiconductor arrangements of the arrangement should lie in the lying span direction. After removing the exposure source U on the base electrode B ₁ with the low, all diodes should be blocked again,
higher (or higher) potential. According to the two Second possibility: With an unexposed arrangement of basic possibilities A, B there are two cases, if only one diode is to be open. If the light beam falls on any other diode in the arrangement, which is briefly shown for arrangements with double base diodes, then this should be presented. 60 switch in the flow direction while the previously open

If you choose the voltage V and the resistors R, the diode flips in the reverse direction. Only one should always

according to the dimensioning option A, one obtains a diode lying in the direction of flow.

Arrangement in which the light struck each time, the first possibility will be examined more closely.

Double base diodes are open, while the rest of them are achieved if one for this according to the invention

Blocking direction lie. After removal of the exposure 65 ensures that the characteristic curve of the resistors R at un-

all diodes go in reverse direction. exposed arrangement the characteristic curve I Uo = f (Id)

If, on the other hand, one chooses the voltage V and the resistors of each double base diode of the arrangement only in one

if R were based on the dimensioning option B, then the only operating point X ₁ intersects in the restricted area,

one an arrangement in which all of the light while they only the characteristics of the exposed diodes

hit double base diodes after removal of the Beiich 70 hits in the flow area. So it is the basic rule A here

7 8

for all diodes of the arrangement, where the F Άτηαχ, below, P ', the voltage Va min to. In order to

variable voltage Va in place of the fixed one is the condition

Voltage V occurs. _. not affected ^ ₁₇ . _{/ TT.} Afraid

Fig. 2 b shows the characteristics of any \ '- Ί)) _{Ιΐ) =} . _ο -> ν a> ■ y-> d) _Ιχ) -. _ο Double base diode of the arrangement for a given 5

Operating voltage U and a given intensity for the two voltage values Va max and Va min of the controlling light signal. I is the characteristic curve in unfulfilled. Since Va max is equal to V because of the negligibility of the exposed state, and II let the characteristic curve in the reverse currents be equal to V, one also has the illuminated state at the same time. The corresponding characteristics of the voltage V are defined. The resistors R are the remaining diodes of the arrangement should be determined as possible according to condition A, b). This can simply cover well with these characteristics. Then this will just be done in such a way that the above requirement is met by point P if, firstly, Va is such an ordinate axis to which the voltage Va max is assigned that, in accordance with condition A, a) for, a resistance line III sets which the characteristic Va always intersects line I only at one working point X ₁ in the stable blocking , jj »unexposed γ, _T j ^ exposed 15 area. The straight line III corresponds to the position \ ^u0 IiJ) = O - ^ ^A ^ ^ DJ ₇ J ₃ = O _the characteristic curve of the resistance with unexposed applies. Arrangement, ie when all diodes are blocked. The Since by which the voltage Va min entder arrangement as a result of exposure to the case of overturning of any double base diode in parallel with III by the speaking point P 'on the ordinate axis designated resistance R ₀ changes the current flowing, it follows from this 20 straight III' indicates the location the characteristic of the WiderCondition level R when one of the diodes is exposed. she

intersects characteristic curve II of the exposed diode naturally

> VAmax, according to only at one working point X ₂ in the flow area.

.exposed The current assigned to this operating point is assumed with

> {Uo)

, -exposed

VAmax is the maximum value of the voltage Va

_refers between the point A at the output of the resistor R _{0th Its value can be found} directly on the abscissa and the base electrode B ₁ . Since the reverse currents of the arrangement to be read are negligible, VAmax ^ V. 30th
On the other hand, VAmin is the minimum value of the voltage Va, ^ ¹¹⁵

which practically only depends on the flow of the exposed double VAmax = V,

base diode according to γ ^ ₌ γ _

₇ V _A mi _n ^ VR ₀ -I ™ ^icht 35 follows

τ / -rj- ρ, -exposed

'Amax - r Amin - λ ₀ · ■> ■ _D $ _lu ß ·

is determined. The size of this river flow depends on

the slope of the characteristic curve of the resistor R. Da Va max - Va min equals the distance between the two

This is in accordance with the condition A, b) points P and P 'and also I _{0 Mu} ß is known, is to be chosen so that the angle of inclination <p _{m of} the resistance 40 also the size of the common resistance R ₀ straight line III is known to be smaller than the angle of inclination $, while the size of R can be read off immediately from the inclination of the curve III on the ordinate (Uzr axis) in height. Point P at the voltage VAmax at the characteristic is favorable if the two points P and P 'are not too close to line I of the unexposed diode tangent T. Under certain circumstances it is also Since Va _ma x is virtually equal to V, one must pay attention 45 that the distance of the point P (is assigned when the first setting option reaching the voltage Va max) of the section Will, Voltage F according to the condition point of characteristic curve II with the ordinate axis greater than ......,., ·,. * ,. is than twice the distance between the two points P and P '.

I _TT \ unexposed _T r ijj ^ keep . ^r \,.

\ ^u d) _{Id = 0} > ν > (Ud) _{Ii) = 0} This means that only one diode of the arrangement

50 flips in the flow direction if two diodes happen to select the same. In addition, the condition must be exposed early. In the interest of a high

. , .. the possibility of the arrangement is also the point P

τι- ^^ UJ \ belicntet °

ν α min ^> \. ^u d) _{Ij) = ü place} as high as possible.

An arrangement sized according to this procedure

to be observed. This ensures that each 55 has the required property that only one exposed diode necessarily in the flow state over diode, and only with exposure, in the flow direction have to go. lies. After removing the controlling light beam

If the first possibility of behavior is switched on, it switches off again automatically. If you want to contradict the regulation, the easiest way to do this is to wait for the individual diodes using the following procedure: Due to the intended exposure intensity to be used, do not tilt, the operating voltage U and the exposure to be used will bring about a slight increase in the same remedy, strength is selected a number of N double base diodes. More interesting than the case just discussed is this

from the point of view of the greatest possible uniformity, the second possibility already mentioned, an arrangement with its characteristic curves I and II. Then one can set the characteristic curves I and 65 together with the resistance R ₀ according to the invention for the N double base diodes using a common determination of the quantities V, R and R _0. II use any diode in the arrangement. In what follows, the aim is to ensure that if the graphic image of these characteristics is not exposed, two arrangements are always only one diode open. If the different points P, P 'on the ordinate axis, the controlling light beam falls on any other diode which lies between the two characteristics I and II of the arrangement, then this should switch in the direction of flow. The voltage 70 is assigned to the upper point P while the previously open diode flips over into S r.

9 10

Only a single diode should always be possible in the flow direction. Inclination angle <p _{m of} this resistance straight line III with

be. the positive abscissa axis (! .D axis) can then

According to the invention, the following conditions are indirectly the associated value of the resistor R for this purpose

required: ■ " can be read off. In the area between point L

a) The characteristic curve of the resistances R should at un- 5 and the point Y ₂ is the resistance line III

exposed arrangement, the characteristic curves I of each double above the characteristic curve I. The largest distance in or-

base diode, of which again the greatest possible direct data direction between the straight line III and the

moderation is to be demanded, at an operating point Y ₁ in the characteristic curve I between the two points L and Y ₂

stable restricted area and denoted by s in another stable.

Working point Y ₂ cut in the flux range, while they io The voltage V , like the voltage Va max, the characteristics II of the exposed diodes can only be specified in the flux range, in compliance with a certain rule, in a single working point Y ₃ . While for Va max the restrictive concern. So for the voltage Va it is the basic condition in the basic requirement B, a) existed, is the rule B, a) and for the (equal) resistances R the choice of V or i? ₀ decisive for compliance with basic rule B, b). 15 condition ß) is fulfilled. Sufficient for the

ß) The characteristic III of the resistors R must - if condition ß) is met, is the requirement
randomly two double base diodes of the arrangement in

Flow area - sink so deep that then with R ₀ > -,

none of the characteristic curves I in the flow area an intersection point * ^D 0 0

is possible. 20 which is now to be derived.

γ) Finally, the flow state of the last two layers must happen to be two if the arrangement is darkened

exposed diode be more stable than the flow state of the diodes in the direction of flow, the characteristic curve of the

previously open diode, so that the last exposed resistance R does not always pass through the point P of the ordinate,

Keep the diode in the forward direction. How this can be achieved, but lead through the point P 'of the ordinate, the

will be explained in more detail. 25 is assigned a voltage Va max . Va is min

If an arrangement with N double base diodes according to

the second possibility is to be set, one goes y _ y , p run-exposed

the easiest way to proceed as follows: On the basis of which to amine - ₀ · ¹ D must

used operating voltage U and the specified. However, this flow stream Id must is not that

turning exposure intensity one chooses a number 30 defined by the operating point Y ₂ flux current, the

of N double base diodes from the point of view of the location of V _A max according to the condition

the greatest possible uniformity of their characteristics I and II y F 7? Doing it

the end. Then one can determine the quantities V, R ^Amax ~ ~ ° 'iJW

and R ₀ the characteristics I and II of any diode is decisive, but it is smaller. Its lowest

use of the arrangement. The normal operating value is defined by an operating point Π, which can be

According to the state, only a double base diode should be obtained if the resistance line III is kept for so long

in the direction of flow when the arrangement is darkened. shifts parallel downwards until it reaches characteristic curve I.

In this case, the voltage drop across the resistor R _{0 is} just affected. Then is the point of contact

least. Is the said working point Π- through it is the current //) (Π)

junbei reports 40 determined. When the arrangement is darkened, the

^{D flow} difference V _A max - VΆ min do not become greater than

the current caused by the open diode (the blocking _{T /} r _T r τ? τ λ-η

... j .. ·. ■ tv jj * j ι ·· "Amax - · V Amin = - ^ o * * D (J I) = S ,

currents of the other diodes of the arrangement can be neglected), so Va is greatest in this case when two diodes are open at the same time. Since Va max and through 45 and s are already fixed and Id (Π) also through the

γ _v D Tun exposes the already determined slope of the resistance line III

Amax "o- * dm _u ß _{and the} course of the characteristic curve I is fixed, one must

given. Since for Va always the condition B, a) is fulfilled _s

must be, so is also R ₀ > ————

IJj % unexposed ^ y ^ ιττ \ exposed 50 JD [I \)

^ ^UD h _D = o> ^v Amax> \ ud) Select _{I [) = 0} so that the condition / 5) is fulfilled. Well is still

to promote. the size V available. She is then chosen by that

Correspondingly, one chooses in the graphic Dar- Va max and the current in the also already defined

position of the characteristic curves I, II as a representative of the operating point Y ₂ , Id (Y ₂ ) according to

used diode on the ordinate axis a point P 55 V = V 4- R I (Y)

between the two characteristic curves I and II and assigns ^max ° ^D

the voltage Va max to this. Given by this point P. Conversely, one can also use V and Va max and R

the resistance line III, which specifies the operating and thus also Id [Y ₂ ), and the resistance R _{0 are placed}

should correspond to the state of the unexposed arrangement from the last equation. But then you have to

in accordance with requirement B, b). Accordingly, care must be taken that the R _{0 obtained in this way is} the

is the resistance line III through the point P of the condition

Ordinate (at the level of the voltage Va max) such as _s

choose that their angle of inclination <p _m with the positive ^ o> j λ— «
The axis of the abscissa is greater than the angle of inclination ϋ · the

by the point P on the characteristic curve I laid tangent T. 65 fulfilled. Where s is the distance by which the dem

This automatically cuts the characteristic curve I normal operation of the unexposed arrangement (a diode

of the unexposed diode at an operating point Y ₁ in the open) corresponding characteristic of the resistors R

stable blocking range, in a stable operating point Y ₂ (namely the straight line III, which passes through the operating point Y ₂

in the flow area uhd another between Y ₁ and Y ₂ leads) must be shifted parallel downwards so that

lying unstable point L in the river area. From the 70 you can just barely enter the characteristic curve I of the unexposed diode

11 12

tangent to a point Π. 7d (Π) is this axis of contact. But it is still so high that it all The current value assigned to point Π, which is immediately read from Characteristic curves I of the unexposed diodes both in the blocking mode can be. area as well as in the river area.

This means that even when the arrangement is darkened, the only open diode in the unexposed arrangement

If a diode is in the forward direction, it is also necessary that the diode be k . By exposing a second

lent that diode of the arrangement, e.g. B. the diode (k +1), also flips

ν> {U _D ) ™ ^indicates this in the direction of flow. First go through the exposure

^v ~ the characteristic of the diode (k- - \ - 1) into characteristic II,

is. Furthermore, for the mode of operation and sensitivity of the other diodes (including the diode k), the characteristic of the arrangement is advantageous if the counter line I is retained. In order for the diode (k + 1) to flip, the positions R would not be significantly smaller than simply necessary because the point P in regulation B, b) is absolutely necessary. Likewise, height V _A max on the ordinate axis, a capital V and a capital R _{0 are} favorable. A high line III of the resistance R the characteristic II only in the position of the point P assigned to the voltage V _{A max intersects an operating point Y 3} in the flow area, since on the ordinate the consequence is that R is selected to be larger 15 until the onset of the tilting Emitter currents cannot become and consequently the distance between change and therefore the unstable intersection point L measured in the idle state and the stable working curve of the resistance straight line III still applies. Becomes small through point Y _2. The above selection of the point P on the ordinate between the arrangement is again advantageous for the sensitivity. The two characteristics I and II produced according to the manner just described is achieved in any case that the characteristic II below the normal arrangement meets all the requirements placed on it. Operating state corresponding straight line resistance III. When the unexposed arrangement is switched on, all diodes are next in the reverse direction when the intended intensity is used. Since the controlling light beam tilts at any time

unexposed exposed diode is guaranteed. By tilting

V > [UD) _I]} _ ₀ 25 the current flowing through the resistor R _{0 increases}

and thus the voltage drop across this resistor.

is selected, at the moment of switching on the voltage Vα thus drops below the value Va max and the characteristic curve of the resistors R the ordinate axis in the line of the resistors R below that of the normal operation of the level of the selected voltage V (since the reverse currents unexposed arrangement ( only one diode is open) can be disregarded), ie above the characteristic position III. The condition γ) lines I now comes into play here. In the first moment after the switch-on, those that have been added in the previous considerations were initially only reset at operating points in the flow area. To the condition γ), according to which the possible. each last illuminated diode in the forward direction remain a result, increase the emitter currents Id and comparable to, and the previously open diode reverse tilt causes the resistor R ₀ is an increasing chip 35, intended to meet, there is according to the invention, two Mögnungsabfall, consequently be the characteristic of disgust: Either one ensures that the distance from Stand R shifts downwards. This state is of the two characteristics I and II at the point of the stable unstable and strives for a stable final state of the operating point Y ₂ in the ordinate direction greater than that

distance s is already defined, or the

Y g _ junbeit __ γ 4o resistors R a capacitor C in parallel.

^{0 D max} ' First, the first possibility will be discussed.

(Voltage drop along A ₀ ) Da. for the / e-diode the characteristic curve I is decisive, must

,, ρ .notified _ _r unexposed ^it must be tilted in the blocking direction as soon as as a result of the

VAmax - λ · ¹ DMust ~~ ^υ D ' exposure of the diode [k + 1) the resistance line around

(Equation of resistance ^ 5 a greater amount than the distance s down

straight line III) because it then no longer intersects with the

Has characteristics I in the flow area. According to the above

jjunbeiichtet ₌ ^ / _{/ U} nbeiichtet \ measurement procedure, the quantities V _A and R ₀ are such

^D , _T _ ^D ™ ^ιβ . ,. ,, chosen that the characteristic of the resistance R at a

(Characteristic equation of the _5o total current 2 I ₁ , (Π) certainly no intersection

unafraid diodes) _point ^ _{the Kenminien} τ _mem - possesses. If you z. B.

is clearly determined. ^{Which after subsiding of} the one ^ ₁ 50Γ ^ ' ^that below the working point Y ₂ the

The operating point Y ₂ setting the switching process is further away from the characteristic curve I than is due to characteristic curve II

the three sizes, ^{ie the} range s, becomes at the moment of tangency the

.unbeiichtet _rr unbeiichtet 55 load line, the total current through the resistance

VAmax, J-Dpiup U ₁ , R _{0 was} greater than 2 Id (Π). While namely through the

unexposed but open diode k the current Id (Π) flows,

set. Since, according to the above VΆ max, V and R , the current through the exposed diode [k + 1) has been chosen such that in the case of an unexposed arrangement it is always only borrowed greater. The characteristic curve of the resistors R decreases so a diode lies in the forward direction and from this R _{0 is} set 60 below the position of the tangent τ on the characteristic curve I, so that, conversely, this R ₀ together with the diode k must flip in the reverse direction. It is particularly favorable if the values V and R corresponding to the basic requirements are - as already mentioned - which ensure that after the switch-on voltage Va max and the resistance R have decayed, only a single point of intersection occurs when the arrangement is darkened L and Y _{2 of} the resistance diode is in the forward direction. From the smallest differences 65 straight III with the characteristics I are close together, between the characteristics I and the slopes of the resistance, it is then achieved with great certainty that the diode standing line III depends on which of the diodes in [k + 1) in the direction of flow is more stable than the diode k, since the direction of flow will remain. In the stable final state, additional minority carriers are generated and therefore the characteristic curve III of the resistors R is fixed and the emitter electrode D of the diode (k + 1) passes through the point P at the height Va max on the ordinate 70 of its semiconductor body (i.e. at alloyed electrode D

the voltage of the pn junction) is more positive than that of the diode k. As a result, the diode (k + 1) maintains the forward direction, while the diode k has to flip in the reverse direction. The use of a high exposure level of the controlling light beam also has a stabilizing effect in this sense.

The second way to ensure that the diode last hit by the light beam remains in the flow direction and the previously open diode switches in the reverse direction, according to the invention, the resistors R, through which the emitter electrodes D with the common resistor R ₀ and the positive pole of the DC voltage source V are connected to be bridged with a capacitor C connected in parallel, ie to connect the electrodes D _{to the resistor A 0} via an i? C element.

3 shows a corresponding arrangement with N = 5 diodes. It is z. B. U = 20 V, V = 50 V, the! B.egiem, ungswideratoren 2ü & = 5 kß, the resistors R = 1 kJÖ and the capacitors C = I μΈ. The resistance R ₀ is dimensioned so that without exposure there is always only one diode in the direction of flow. The controlling light beam is guided in such a way that it falls on one diode of the arrangement after the other. Assume that it falls on the diode k, which is in the forward direction. From here it may move to the neighboring diode (k + 1). Then the diode k also flips in the forward direction. As a result, the potential Va of the point A becomes even smaller, so that the diode k has to tip over in the reverse direction. Since the capacitor C is not yet charged in the newly ignited diode, the inrush current initially flows into this capacitor, so that the resistor R is short-circuited through it. Therefore, the potential of the electrode D of the newly ignited diode (k + 1) is higher than that of the diode k, which was previously in the direction of flow. [In addition, as described above, the diode (k + 1) is in any case more stable than the diode k in the forward direction without the effect of the capacitor C. This must therefore tilt in the reverse direction for both reasons.] The size of the capacitor C is to be determined in conjunction with the size of the resistor R so

agree that the time constant Θ = - ^ ₇ T is greater than

the time it takes for the diode k to flip in the reverse direction again.

The use of the AC elements instead of simple resistors also makes it possible for the individual diodes to tip over from the reverse direction to the flow direction by means of short flashes of light. The term "short" here means that the duration of the individual flashes of light is shorter than the service life of the minority carriers in the semiconductor body of the diodes. Since the tilting of the diodes requires a finite time, the following case is possible: The diode k of the unexposed arrangement is initially in the direction of flow. Another diode of the arrangement, e.g. B. the neighboring diode (k + 1) is hit by a short flash of light. It also comes in the direction of the river. Then with the again darkened arrangement there are two diodes in the flow direction immediately after the light irradiation. This state is not stable: one of the two diodes has to flip in the reverse direction again. The 2? C elements now ensure that the last exposed diode (k + 1) always remains in the direction of flow.

In order to make the arrangements according to the invention for switching or regulating purposes available, you will be in the individual circuits DVB ₁ or B ₂ UB ₁ for each diode in the array a special feeler z. B. provide the primary coil of a relay. However, it is more convenient to attach a further electrode K which acts as a collector to the semiconductor body of each diode and which then emits the increased switching capacity via a load resistor R (cf. FIG. 3). The double base diode has thus become a double base transistor. The presence of another, e.g. B. in η-conductive semiconductor bodies negatively biased against B ₁ electrode changes nothing in the tilting mechanism of the individual thread semiconductors, but it has the advantage of particularly good utilization of the switching energy supplied by the arrangement. Each of the arrangements described allows the use of double base diodes and double base transistors alike.

Likewise, it is not necessary that the semiconductor bodies are η-conductive, p-conductive semiconductor bodies can can be used in the same way in the arrangements according to the invention. However, then the individual Reverse biasing accordingly.

Claims (8)

Patent claims: 1. Switching arrangement controllable by a light beam with a thread semiconductor arrangement, e.g. B. a double base diode, with an η-conductive (or p-conductive) semiconductor body and two base electrodes contacted without a barrier layer, which - if necessary via a limiting resistor - are connected to a DC voltage source, as well as with at least one other positive (or negative) against the negative (or positive) base electrode biased emitter electrode which injects minority carriers into the semiconductor body of the thread semiconductor arrangement above (or below) a certain bias voltage, the emitter electrode being connected to the positive (or negative) pole of a DC voltage source via an ohmic resistor, characterized in that the resistor (R) and the voltage source (F) are dimensioned such that the characteristic (III) of the resistor (R ) corresponds to the characteristic (I) associated with the operating voltage (U) between the base electrodes (B ₁ , B ₂₎ ) the unexposed thread semiconductor arrangement in at least one working point in the stable areas intersects this characteristic curve, while it meets the characteristic curve (II) of the exposed thread semiconductor arrangement belonging to the same operating voltage (U) _{only at one operating point (X 2} ) in the pass band. 2. Controllable by a light beam circuit arrangement according to claim 1, characterized in that the resistor (R) and the voltage source (F) are dimensioned such. That the characteristic curve (III) of the resistor (R) to the operating voltage (Ϊ7) between the Base electrodes (B ₁ , B ₂ ) associated characteristic curve (I) of the unexposed thread semiconductor arrangement intersects only in a single operating point (X ₁ ) in the stable blocking range of this characteristic curve. 3. Controllable by a light beam switching arrangement according to claim 1, characterized in that the resistor (R) and the voltage source (F) are dimensioned such that the characteristic curve (III) of the resistor (R) to the operating voltage (U) between the base electrodes (S ₁ , B ₂ ) associated characteristic curve (I) of the unexposed thread semiconductor arrangement _{intersects this characteristic curve at an operating point (Y 1} ) in the stable blocking range and at a further operating point (Y ₂ ) in the stable transmission range. 4. Semiconductor arrangement controllable by a light beam according to one of claims 1 to 3 for switching or regulating, characterized in that η similar arrangements according to one of claims 1 to 3 selected to be the same in the size of their switching elements are connected in parallel in such a way that each of the emitter electrodes ( D) via a resistor (R) each with the positive (or negative) pole a common voltage source (F) are connected, the negative pole (or positive pole) and the negative pole (or positive pole) of a second _{voltage source (C /) located between the base electrodes (B 1} , B ₂ ) of all thread semiconductor arrangements used on the base electrode (B ₁ ) with the lower (or higher) potential. 5. Arrangement according to claim 4, characterized by a further ohmic resistor (R ₀ ), which is connected between the η switching elements and the common DC voltage source (F), which supplies the bias of the emitter electrodes (D) , that it and the resistors (R) lie in series. 6. A circuit arrangement according to claim 5, characterized in that the voltage of the DC voltage source ¹ S (F), which the bias of the emitter electrodes (D) provides, and each switching element assigned equally large resistors (R) and the common resistance (R ₀ ) are dimensioned in such a way that the characteristic curve (III) of the resistors (R) in the unexposed arrangement shows the characteristic (I) of each double base diode of the arrangement corresponding to the unexposed state of the diodes at an operating point (Y ₁ ) in the stable blocking range and in a further sta - Bile working point (Y ₂ ) intersect in the flow area, while it meets the characteristic curves (II) corresponding to the exposed state, if a diode of the arrangement is considered, only in the flow area. 7. Switching arrangement according to one of the preceding claims, in particular according to claim 6, characterized in that the resistors (R) assigned to each of the double base diodes of the arrangement are each connected to a capacitor (C) with the same capacitance in each case, so that the emitter electrodes (D) are each connected to the common resistor (R ₀ ) via an identical i? C element. 8. Circuit arrangement according to one of the previous claims, characterized by the use of double-base transistors having yet another acting as KoUektor electrode (K), the negatively via a load resistor (A ₁₎ (or positive) to the base electrode (B ₁₎ are biased with the lower (or higher) potential, and the switching capacity at the resistor (R _L ) is removed. Considered publications:
German interpretation document No. 1 053 030. 1 sheet of drawings 009 5 + 9/297 6.60