SU1238228A1 - Switching device - Google Patents

Abstract

The invention relates to electronic switching technology and can be used as a switch for multi-phase signals, switching devices, etc. The aim of the invention is to increase the reliability of the switch by reducing the number of elements and allowing the use of MOS transistors, including controlled resistances, with threshold voltages that are not critical to the magnitude of the control voltages. The goal is achieved by introducing into the control device of the switch a multi-current MOS transistor and a third control field. The device contains controllable resistances on MOS transistors 1, 2 and 3, respectively, in the first, second and third channels, diodes 4, 5, 6, 7, 8 and 9, which function as gates, input 10, 11 and 12, and output 13, 14 and 15 wages, a control device 16, a tristok MOS transistor 17, control wiring 18, 19 and 20 and a common busbar 21. Il. 2 to with 00 oo 1C 00

Description

The invention relates to electronic switching technology and can be used as a switch for multi-phase signals, switching devices, etc.

The aim of the invention is to increase the reliability of the switch by reducing the number of elements and connections, the possibility of using MIS transistors, incl. and as controlled resistors, with threshold voltages not critical to the magnitude of the control voltages by introducing a multi-current MOSFET and a third control bus into the switch control device.

FIG. Figure 1 shows a circuit diagram of a switch of three-phase alternating signals into loads connected by a triangle using diodes as valves, and a MOS transistor as controlled resistance; in fig. 2 is a schematic diagram of a switch of unipolar signals to a star-connected load into three channels.

Field-effect transistors with a pn junction and MIS transistors both with depletion and enrichment can also be used as controlled resistance.

The switchboard contains controlled resistances (MOS transistors) 1, 2 and 3, respectively, in the first, second and third channels, the first valves (diodes) 4, 5 and 6, the second valves (diodes) 7, 8 and 9, input rails 10, 11 and 12, output lines 13, 14 and 15, a control device 16, a three-line MOS transistor 17, control buses 18, 19 and 20, a common bus 21.

Opposite terminals of the first 4 and second 7 diodes, for example, in the first channel are connected to the input bus 10, the free output of the first diode 4 is connected via a controlled resistance (MOS transistor) 1 to the free output of the second diode 7, which is connected to the output bus 13. Controlled resistances (MOS transistors) 1, 2 and 3 are connected to the first control bus 18 of the control device 16. The source of the three-path MOS transistor 17 and its gate are connected to the second 19 and third 20 control buses, the drains of the three-drain MOS transistor 17 are connected to the junction points of the first diode and the controlled resistance of the corresponding channel.

The first and third control sleeves can be connected.

The switch works as follows.

Sign-changing signals from input sources connected to a star are supplied to the input slots 10, 11, and 12.

In the closed state of the switch, positive potentials are applied to the first 18 and third 20 control buses relative to the second 19 control field, while the MOS transistor 17 is open and

a more positive potential from the input signals, for example, from the input bus 10, through the first diode 4 is transmitted to the bus 19 and then to the buses 18 and 20, shifting the sources of control signals by

this potential in a positive direction. A sample of the most positive potential and recharges of 19–20 ensures high resistance of all control resistances 1, 2, and 3 for any

combinations of input signals (even if their amplitude significantly exceeds the magnitude of the control voltages). The current through the load while not flowing.

When the switch is switched, the polarities of the isolated control sources are reversed, the MOS transistor 17 closes and the controlled resistances 1, 2 and 3 take on small values corresponding to the resistances of the channel of the open MOS transistor. At the same time, the least positive potential from the input signals through the second diode 8, the open MOS transistor 2 and the displaced drain diode of the MOS transistor 17 shifts the potentials of the control systems by the value of this least positive potential. Sampling the least positive potential from the input signals and transferring it to the control inputs of the controlled resistances 1, 2 and 3 ensures their low resistance and the flow of currents in the loads, for example, in the circuit: input bus 10 - diode 4 - controllable resistance 1 - output bus 13 - load - diode 8. Similarly, the current flows in the load between the buses 14 and 15 through the third channel comm. tator, if the input signal on the bus 11 is the least positive.

The use of a smooth control of the source of the controlled signal connected to the first control bus 18 ensures the operation of the device as an attenuator.

The device in FIG. 2 is distinguished by the fact that it does not have second diodes 7, 8, and 9, which ensures the switching of only unipolar signals. The operation of the device is similar to the operation of the device of FIG. one.

5 Sampling the least positive of the potentials of the input signals to bias the controlled sources allows the proposed device to be used additionally as a logical switching device, for example, channel voltage comparison devices, threshold devices, etc. This is done by modulating the magnitude of the controlled resistance 1, 2, 3 by changing the gate voltages to the source of the corresponding MOS transistors by the input voltage of the channel, the voltage

5 which is least positive.

With an appropriate choice of control and input voltages in the open state of the switch, it is possible to provide

five

0

current flow into loads from only one channel, the input voltage of which is the greatest.

Claims (1)

Invention Formula The switch containing the first and second valves, the controlled resistance in each channel and the control device with the first and second control buses, the opposite terminals of the first and second valves are connected to the input bus of the channel, the free output of the first valve through 10 ff- ,20 Jj ff the control resistance is connected to the output bus of the channel and to the free output of the second valve, the control inputs of the control resistances of all channels are connected to the first control bus of the control device, characterized in that, in order to increase reliability, the control device is designed as a multi-stream MIS a transistor, each of the drains of which is connected to the connection point of the first valve and the controlled resistance of the corresponding channel, and the source and gate to the second and third control buses of the control unit gov. / Lt f WITH (pus. 2