SU480190A1 - Switching device - Google Patents

Description

The invention relates to radio engineering, can be used for switching parametric primary impedance converters.

A switching device is known, its device containing an autonomous control unit with an interface unit to which binary-decimal counters with decoders are connected, as well as a display device, key first-order MOS transistor arrays and key second-stage MOS transistor.

The purpose of the invention is to increase the reliability of the device, which is achieved by introducing two additional diode-opto-matrix arrays into the proposed device, the first of which is connected to the control buses of all the key first-stage MOS transistor arrays connected in parallel to the control rails, key matrix of the second stage. In this case, the first optocoupler array is connected to the outputs of two decoders, and the second to the output of the third decoder; The key MOS transistor arrays of the first and second stages are connected to an additional compensation block.

FIG. 1 shows a block diagram of a switching device; in fig. 2 shows diode-optocoupler matrices with a device

management; in fig. Figure 3 shows an electrical circuit diagram of a key MOSFET matrix with a compensation unit.

The switching device contains an autonomous control unit 1, connected to the interface unit 2, to which information from the computer arrives, binary-decimal counters 3-5, display device 6, decoders 7-9, which convert the binary code to decimal; diode-optical matrices 10, 11. Counters 3-5 are associated with block 2 and decoders 7-9. Decoders 8, 9 control the diode-optocoupler

matrix 10, and the decoder 7 - diode-optocoupler matrix 11.

The key MOS transistor matrices 12 (in this case, 16 matrices are considered) of the first switching stage are connected in parallel to the output of the diode-opto-matrix 10. Key M, the OP-transistor matrix 13 of the second switching stage is controlled by signals from the diode-opto-matrix 11.

In order to actively compensate for the resistances of communication lines and the resistances of sequentially connected open key elements of the first and second stages, a compensation unit 14 is connected to the matrices 12 and 13.

The device works as follows.

When submission of control codes from the autonomous control unit 1 or the interface unit 2, a certain number is entered into the binary-decimal counters 3-5. Decoders 7-9 convert the binary code to decimal, and the corresponding potentials from the decoders 8, 9 (Fig. 2) control the diode-optocoupler 10. Only one optocoupler is lit.

To control the MOSFET, it is necessary to apply a full potential equal to the maximum positive value of the signal being tested to its gate. For this purpose, the sources 15-24 are united by a common tire to which a positive potential is applied.

The negative potential supplied to the common photodiode bus is selected from the conditions of the required control modes of the MOS transistors and taking into account the series connection of the key elements of the first and second switching stages.

From the diode-optocoupler array, one hundred control lines emerged that are connected to the corresponding control inputs of the key MOS transistor arrays 12 (for example, a field with potential U is connected to the first inputs, with potential Uz - to the second inputs, etc.) (Fig. 2, 3). For example, at a negative potential f / i (Fig. 3), MOS transistors 25, 27, 29, 31, 33, 35, 37, 39 are opened (open MOS transistors in Fig. 3 are conventionally circled). To control the second switching stage (Fig. 2), the binary code from counter 5, converted to decimal decoder 7, lights one of the optocouplers. Thus, a negative potential (e.g., Ui) is applied to the control inputs of the MOS transistor matrix 13 of the second switching stage.

In this case (Fig. 3), only MOS transistors 43, 44, 46, 48 are opened. Thus, only the primary converter is connected to the compensation unit. MOS transistors 27, 42 and 35, 36 form switched power circuits, and MOS transistors 31, 44 and 39, 48 form negative feedback loops. Thus, the compensation unit compensates for the nominal resistances of the connecting lines and the resistance

consistently included, open MOPtransistors and their variations. Therefore, variations in the resistances of the connecting lines and series-connected open MOS5 transistor key elements from changes in external climatic conditions do not affect the metrological characteristics of the device. For the commutation of a large number of primary transducers, only two operational amplifiers are necessary, since the switching takes place sequentially or addressally, but in all cases to the input of the measuring device (points 49 and 50 in Fig. 3)

5, only one primary transducer is connected.

The use of optoelectronic elements in control circuits allows the use of a matrix control circuit and significantly reduce the number of logic elements in decipherors.

In addition, with these elements, complete galvanic isolation of the levels of control logic signals from

5 levels of signals in the measuring circuit.

Subject invention

A switching device containing

0 an autonomous control unit associated with an interface unit to which binary-decimal counters with decoders are connected, as well as a display device, the key MOS-transistor arrays of the first

5 steps and a key MOP transistor matrix of the second stage, characterized in that, in order to increase its reliability, two additional diode-nitron matrices are introduced in it, the first of which is connected to the control buses of all the first-stage MOS transistor matrices connected in parallel to the controllers, the second with the second-stage key matrix, the first optocoupler 5 per matrix connected to the outputs of two decoders, and the second to the output of the third decoder, with the key MOS transistor arrays n rvoy and second stages coupled to the complementary box

0 compensation.

-Pf- rn IUi I

r.-i

iv,

-31:

&

49

L

Phage.