DE2450122C2 - Circuit arrangement for the logical combination of AC input signals - Google Patents

Description

characterized in that for the realization of a safe interconnection of a number of logical, fail-safe logic elements, the connection of a module output (A or A 'or A "... ) with the inputs (E \ .., E _n or E '\, .. , E'" or E" ,, .. , t " _a -...) of a number of further downstream modules (V _x , ... , V _n or V ₁ , .. " V _n , or V _1. .., V _n · ..) by connecting the corresponding primary input transformer windings in series (W _x , ... , W _n or W _x , ... , W ₀ , or W _x , .. , W _n - ... ), whereby at the end of the last input transformer winding (W _n or W _n or W _n - ...) the generation of the AC input signals is used Battery voltage (Ue) is applied as the supply voltage for the output amplifier stage of the respective preceding module (V or V ₁ or V, ...).

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The invention relates to a circuit arrangement for the logical combination of alternating voltage miger input signals to an alternating voltage output signal with the combination of the following Characteristics:

a) that the input signals are fed to separate input transformers and in their secondary circuits are rectified by switched on rectifier arrangements,

b) that the rectified input signals form the individual control potentials for a downstream transistor blocking oscillator circuit with feedback transformer,

c) that the pulse voltage of the blocking oscillator over

an amplifier stage connected to the secondary circuit of the feedback transformer is fed to the output, according to main patent 19 33 713, and in the case of the doping of the transistor used in the blocking oscillator circuit as follows it is selected that the one used to generate the input AC voltage signals Battery voltage has the opposite polarity to that of the blocking oscillator circuit required and depending on the AC voltage signals by the transformers and Having rectifier circuits generated operating voltages, according to additional patent 23 59 125.

Such a circuit arrangement fulfills the task of operating in a fail-safe manner with a binary effect. Failure safety is understood to mean that if any errors occur within and outside of the Components must never have a dangerously faulty output signal, d. H. that the output signal in In the event of an error, there must be an O signal (voltage = 0).

In particular, it is ensured that a galvanic No dangerous output signal (L signal, voltage = 0) in the input transformers can lead, since the doping of the transistor used in the blocking circuit is selected so that the battery voltage used to generate the input AC voltage signals has the opposite polarity to that of the Blocking oscillator circuit required and depending on the AC voltage input signals the transformer and rectifier circuits has generated operating voltages. Each such circuit arrangement in itself forms a logic module.

For modules that are constructed according to the main patent 19 33 713, it is already known to connect an output line of a module with the inputs of other modules to connect, see Techn. Mitt. AEG-TELEFUNKEN 62 (1972) 4/5. P. 176-178, Fig. 3. The inputs of the modules are current controlled. The combination of an output signal with several inputs is made possible by the The respective input windings are connected in series, with the end of the last input winding being connected to the positive voltage potential will. The series connection causes a safe coupling of the inputs with each other and thus a Forced guidance. The inputs are low-resistance and therefore insensitive to interference voltages. the Wiring for the modules or printed circuit boards with one another is problem-free.

The object of the present invention is to provide a large number of logical, fail-safe connection elements after the additional patent 23 59 125 switch together so that the resulting overall circuit again represents a logical fail-safe circuit arrangement.

According to the invention, this object is achieved in that, in order to implement a fail-safe interconnection of a number of logical, fail-safe connection elements, the connection of a module output A or A 'or A "... with the inputs E \

..., E _n or E \ E '" or £" 1 £ "V · ..a number

further downstream modules V \ V _n or V _x ,

..., V _n -, or Vi, ..., V _n -... by connecting the corresponding primary input transformer windings in series

VV, W _n or W '\ W _n , or W \ W _n -...

is made, with the end of the last input _{transformer winding W n} or W "-bzw. W _n -...

the battery voltage Ug used to generate the AC input signals is applied as the supply voltage for the output amplifier stage of the respective preceding module V or Vj or V '\ ....

The advantage of the solution according to the invention lies in the following: In the event of any insulation faults and thus connected any transition resistances between the primary and secondary windings of both the The input as well as the output transformer can handle the external battery voltages even in the most unfavorable Trap (defective rectifier diodes etc.) when they reach the transistor used in the blocking oscillator, As a matter of principle, do not stimulate this to erroneous vibrations.

The ring transformers used in the linkage elements have a diameter, for example of only 1 mm, so that thermal and / or mechanical stress can easily lead to an insulation fault.

The solution according to the invention allows complex and costly structural measures in the Manufacturing the transformer to avoid insulation faults and offers moreover more safety, because no matter how great a constructive effort, a defect in the transformer can never be ruled out can be.

Furthermore, it is advantageous that the series connection of the primary windings provides a fail-safe Coupling of the inputs with each other is guaranteed. If the wiring is interrupted, in Series connected inputs O signal.

An exemplary embodiment according to the invention will now be explained with reference to the figure

The individual links are labeled V, Vi, .., V _m V ',, .., W

An oscillation generated internally in module V is decoupled via the output transformer O and through the transistor stage T, which supplies its supply voltage Ub via the series-connected primary windings Wi, .., IV _{n of} the input transformer of the modules Vj, ..., V connected downstream of the module V _n is given, amplified on output A.

The primary windings Wj, .., W _n represent part of the collector resistance. The collector current clocked by the oscillation generated internally in the module V represents the input signal for the inputs E _u -., E _n of the modules Vi, .., connected downstream of the module V. V _n represents.

Each module has one or more output amplifier stages (with multiple outputs) of the type described above. For the sake of clarity, this is only shown for module V from the For the same reason, it has been omitted in the figure for the individual link elements further inputs or outputs, which in turn with other (not shown) logic modules are linked. There are (-.; Numerous branches conceivable.

In the example of FIG. 1 controls the logic element V the modules Vi, .., V _n with the same signal, whereby the signal output by Vj in turn controls _{the modules i "i, .., V n etc.}

The battery voltage U _B is selected so that it has the opposite polarity to the polarity in the blocking oscillator circuits of the modules Vj, .., V _n or V ',, .., V _n - or V "i, .., V _n - has required operating voltages of the transistors used there

If, for example, pnp transistors with a negative operating voltage corresponding to this doping (derived from the input signals after rectification and smoothing) are used in the logic elements for the transistor blocking oscillators, Ub must be positive.

1 sheet of drawings

Claims (1)

Claim: Circuit arrangement for the logical combination of AC input signals to form an AC output signal the combination of the following features: a) that the input signals are fed to separate input transformers and in their secondary circuits by switched on rectifiers Orders are rectified, b) that the rectified input signals represent the individual control potentials for a downstream transistor blocking oscillator circuit form with feedback transformer, c) that the pulse voltage of the blocking oscillator is fed to the output via an amplifier stage connected to the secondary circuit of the feedback transformer, according to main patent 19 33 713, and in which the doping of the in the blocking oscillator circuit used transistor is chosen so that the for Generating the input AC voltage signals, the battery voltage used in each case polarity opposite to that required by the blocking oscillator circuit and in Dependence on the alternating voltage signals generated by the operating voltages generated by the transmission and rectifier circuits has, according to additional patent 23 59 125,