SU1287278A1 - Switching device with variable structure - Google Patents

Abstract

The invention relates to a pulse switching technique. It can be used as a power switch in automatic control systems. The purpose of the invention is to increase efficiency and increase speed. For this purpose, three MOS transistors 3, 4 and 5j are introduced into the device, which together with the bipolar transistor 2 of the key form two parallel switching circuits. The device contains a transistor switch 1, a current sensor 6, a threshold element 7, an IC element 8, terminals 11 and 1 h of the power supply, a load 10, the drain of the first MOS transistor 3 is connected to the emitter of a bipolar transistor 2, the base of which is connected to the source the second 4 and the drain of the third 5MDP transistors. The drawing also shows: the common bus .12 and the control bus 20 of the device, the first 9 and the second 13 output terminals of the transistor switch, the first 18 and the second 19 control terminals of the transistor switch. 1 il. i SL

Description

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The invention relates to a pulse switching technique and can be used as a power switch in automatic control systems.

The aim of the invention is to increase the efficiency and increase the speed of the device by re-switching the conductive circuits of the transistor switch during overloads, introducing a second control of the key input and using a switching point to accelerate the switching of the transistor switch. The goal is achieved by the introduction of three MOS transistors, which, together with the bipolar key transistor, form two parallel switching circuits.

The drawing shows the functional diagram of the device.

The device contains a transistor switch 1, a bipolar transistor 2, a first 3, a second 4 and a third 5 MOS transistors, a current sensor 6, a threshold element 7, an AND-NE element 8. The collector of a bipolar transistor 2 is connected to the drain of the second MDP- transistor 4 and is connected to the first output terminal 9 of transistor switch 1, which

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the zero signal is relative to the common 12. The first 3 and second 4 MOS transistors are closed, and a third of the MOS transistor 5 is open and maintains the closed state of the bipolar transistor 2. The switching circuits formed by the MOS transistors 4 and the bipolar transistor. 2, MD transistor 3, open, and the current through the load 10 does not leak. The voltage on the current sensor 6 is zero and the output signal of the threshold device 7 is also zero.

In the open state of the devices, a control signal 20 is supplied to the control bus 20, which opens the transistors 3 and 4, and a conductive circuit is formed between the first and second 13 output terminals of the transistor switch 1, as a result of the load from the power source the transistor switch 1, the sensor ka 6 current flows.

As long as the magnitude of this current does not exceed the nominal value, the signal at the output 17 of the threshold element remains equal to zero and the third MD transistor 5 is open. The fall of a nap on this transistor is

through the load 10 is connected to the first transition base-emitter bipolar

the zero signal relative to the common bus 12. The first 3 and second 4 MOS transistors are closed, and the third MOS transistor 5 is open and maintains the closed state of the bipolar transistor 2. The switching circuits formed by the MOS transistors 4, 5 and the bipolar transistor .2, the MOS transistor 3, is open, and the current through the load 10 does not flow. The voltage on the current sensor 6 is zero, the output signal of the threshold device 7 is also zero.

In the open state of the device, a single signal is supplied to the control bus 20, which opens the MOS transistors 3 and 4, and a current-conducting circuit is formed between the first 9 and second 13 output terminals of the transistor switch 1, resulting in 10, the transistor switch 1, the current sensor 6 current flows.

As long as this current does not exceed the nominal value, the signal at the output 17 of the threshold element 7 remains equal to zero and the third MOS transistor 5 is open. The voltage drop across this transistor is such that

base-emitter transition bipolar

power supply terminal 11. The sources of the first 3 and third 5 MOS transistors are connected to the common bus 12 of the device and to the second output terminal.

13 transistor switches, which are drawn on these MOS transistors with

The sensor cut 6 is connected to the second terminal 14 of the power supply. The output 15 of the current sensor 6 is connected to the input 16 of the threshold element 7, the output 17 of which is connected to one of the inputs of the NAND element 8. The drain of the first MOS transistor 3 is connected to the emitter of bipolar transistor 2, the base of which is connected to the source of the second 4 and drain third 5 MOS transistors. The output of the NAND element 8 is connected to the first control input 18 of the transistor, and the combined gates of the first 3 and second 4 MOS transistors are connected to the second control input 19 of the transistor switch 1, which is connected to the second input of the AND 8 element and control bus 20 of the device.

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The device operates as follows

in a way.

In the closed state of the key to the control bus 20 of the device is fed

transistor 2 is closed and the current flows only through the circuit formed by MOS transistors 4 and 5. Power loss in the switch caused by a fall in current flow less than the nominal one is small — less than the power loss in the circuit formed by the bipolar transistor 2 and the first MOS transistor 1 with the same current. A single bischlard transistor would also have a high impedance voltage, given that the switched circuit is high.

When the device is turned on through the open third MOS transistor 5, the gate-source capacitance of the second MOS transistor 4 discharges: 7 the transistor 4 closes and the current through the load ceases.

If, with the device turned on, the current through the load and, therefore, through the sensor exceeds the nominal value, the key structure changes. The threshold element 7 generates a single signal, the output signal of the element IS-HE 8 produces a zero signal, which closes the MIS transistor 5, the voltage at the base of the bipolar trans

Zistor 2 increases and it is unlocked. The load current flows through the circuit of a series-connected bipolar transistor 2 and the first VDP transistor 3. This circuit, despite large power losses, has a greater load capacity. This mode is implemented only in case of overloads, for example, when switched on and in other short-term modes.

The bipolar transistor 2 is saturated because of the high resistance of the high-resistance collector region due to high-voltage pn junctions, and its degree of end increases with increasing current. When the device is disconnected, the first MIS transistor 3 closes, breaking off the emitter-base current, and the third MOS transistor 5 is opened, creating a low-resistance circuit for resorption of carriers from the collector region and the base-collector transition of the bipolar transistor 2. As a result, the turn-off time is reduced.

Thus, at nominal

load currents in the transistor switch uses an economic circuit,

consisting of high voltage second

torque switch made on a bipolar transistor, current sensor, time. The second element, the IS-NE element, the collector of the bipolar transistor is connected to the first output terminal of the transistor switch, which is connected to the first terminal of the power source through the load, the second output terminal of the transistor switch is connected to the second power source terminal, the current sensor output is connected to the input of the threshold element, the output of which is connected to one of the inputs of the NAND element, the second input of which is connected to the control bus of the device, and the output to the first control input of the transistor switch, chayuschees in that, for the purpose povteni efficiency and improve performance, three key .in transistor MISFET introduced, a drain of the first MIS transistor is connected to the emitter of a bipolar transistor whose base is connected to the source of the second and third MIS drain; transistors, the gate of the third MOS transistor is connected to the first control input of the transistor switch, and the source is connected to the common bus

of the MOSFET 4 and the low-voltage device 30, the source of the first MOSFET of the third MOSFET 5. The transistor and the second output terminal-p

high load currents are used by the nd transistor switch, the drain of the second

The circuit of the bipolar transistor 2, ar of the MOS transistor is connected to the device when the device is switched by both the center of the bipolar transistor,

pi interact, providing high-level gates of the first and second VDP-trans-R and & . The resistors are connected to the second control terminal of the invention on the input of the transistor switch.

A switching device with a variable that is connected to the control bus

structure containing a transis device.

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torque switch made on a bipolar transistor, current sensor, time. The second element, the IS-NE element, the collector of the bipolar transistor is connected to the first output terminal of the transistor switch, which is connected to the first terminal of the power source through the load, the second output terminal of the transistor switch is connected to the second power source terminal, the current sensor output is connected to the input of the threshold element, the output of which is connected to one of the inputs of the NAND element, the second input of which is connected to the control bus of the device, and the output to the first control input of the transistor switch, chayuschees in that, for the purpose povteni efficiency and improve performance, three key .in transistor MISFET introduced, a drain of the first MIS transistor is connected to the emitter of a bipolar transistor whose base is connected to the source of the second and third MIS drain; transistors, the gate of the third MOS transistor is connected to the first control input of the transistor switch, and the source is connected to the common bus

Devices, the source of the first TIR

Claims (1)

SUMMARY OF THE INVENTION A switching device with a variable structure containing a transistor is connected to the first control input of the transistor switch, and the source is connected to the device’s common bus • 30, the source of the first MOS transistor and the second output terminal of the transistor key, the drain of the second MOS transistor is connected to the collector of the bipolar transistor, 35 and the gates of the first and second MOS transistors * are connected to the second control input of the transistor switch, which is connected to the control bus of the device.