SU758481A1 - Device for transfer of potential with galvanic isolation - Google Patents

Description

(54) DEVICE FOR TRANSFER OF POTENTIAL WITH GALVANIC ALIGNMENT

Claims (2)

The invention relates to a pulse technique and can be used to match digital computing devices with external subscribers. A device for transmitting galvanically isolated constant voltage levels, comprising a control transistor, a pulse transformer, brought into a dynamic state by pumping pulses of an external generator, a key and an output transistor 1, is known. The closest technical solution is a device containing input transistors keys, two pulse transformers brought into dynamic state by pulses of pumping an external generator, the primary winding of the second of which is connected to emitters input key transistors, output transistor switches, whose outputs are connected to the corresponding trigger inputs, the primary winding of the first pulse transformer is connected via diodes connected to the transistor collectors of the input transistor switches, and the secondary windings of the second pulse transformer are connected respectively to the collectors and the bases of the second transistor switches 2 A disadvantage of the known devices is the presence of an external source of "pumping the complicating circuit and the source to .m high-frequency interference in the equipment. The aim of the invention is to increase the reliability of operation while reducing energy consumption. The goal is achieved by the fact that a galvanically isolated potential transfer device containing an input transistor switch, in the collector circuit of the transistor of which the primary winding of the pulse transformer is connected, two secondary windings of which are connected in series, and their connection point is connected to the negative power supply bus, Two diodes and a discharge transistor, the base of which through a resistor is connected to the connection point of the secondary windings of a pulse transformer, is introduced a cumulative cond Sensor and field-effect transistor, the gate of which is connected to one plate of the storage capacitor, collector of the discharge transistor and through the first diode to the output of one of the secondary windings of a pulse transformer, the output of the other secondary winding of which through the second diode is connected to the base of the discharge transistor whose emitter is connected with the second plate of the storage capacitor, the negative bus of the power supply and the source of the zero transistor, the drain of which is connected via an additional resistor to the positive side bus power source. The drawing shows the principle electrical circuit of the device. The device contains an input transistor switch 1 on transistor 2, resistors 3., 4 are connected to the base of transistor 2, the emitter of transistor 2 and the second end of resistor 4 are connected to the negative bus 5 of the source potential, the collector of the primary winding of the transformer is connected to the collector of the transistor 2 6, the end of this winding and the second end of the resistor 3 are connected to the positive bus 7 of the source of transmitted potential, the secondary windings 8, 9 of the pulse transformer 6 are connected in series. The connection point of the beginning of the winding 8 and the end of the winding 9 is connected to the negative bus 10 of the power supply, the end of the winding 8 through the diode 11 is connected to one plate of the capacitor 12, the gate of the field-effect transistor 13 and the collector of the transistor 14. The beginning of the winding 9 through the diode 15 is connected to the base transistor 14. The emitter of transistor 14, its base through a resistor 16, the second capacitor 12 face, and the source of the FET 13 are connected to the negative bus 10 of the power supply, the drain of the FET through the resistor 17 is connected to a positive w Ine 18 power source. The device works in the following way. In the initial state, in the absence of a positive potential on the bus 7 and in the presence of a power supply on the field-m transistor 13, the transistors 2, 14 are closed. In the initial state, the current consumption is zero. At exit 19 there will be a high level of potential. When a positive potential is applied to the bus 7, the transistor 2 opens, a current flows across the primary winding of the pulse transformer 6. A pulse of positive polarity induced at the end of the secondary winding 8 is applied through the diode 11 to the end; the sensor 12 is charged and loaded; the field tracer of the sensor 13 opens and a low potential level appears at exit 19. The time during which the open-state; o; ieiiO o transistor 13 iipi cpcce on IIIHHV 7 pi / s / t is used; T; ui; . depends on /: capacity. the leakage current of capacitor 12 and the input resistance of the field-effect transistor 13. When the positive potential is removed from the bus 7 on the secondary winding 9 of the pulse transformer 6, a positive polarity pulse is induced, which through the diode 15 enters the base of the transistor 14 and opens it, the capacitor 12 discharges through the low resistance of the open transistor 14, the field effect transistor 13 is closed. The device is reset. Thus, the device provides the transfer of potential with galvanic isolation with the fulfillment of the function of inversion. This achieves a simplification of the circuit, an increase in the reliability of operation while reducing power consumption. The invention The device for the transfer of potential with galvanic isolation, contains the input transistor switch, in the collector circuit of the transistor which includes the primary winding of the pulse transformer, two secondary windings of which are connected in series, and their connection point is connected to the negative power supply bus, two diodes and a discharge A transistor, the base of which through a resistor is connected to the connection point of the secondary windings of a pulse transformer, characterized in that, in order to increase the reliability operation with a simultaneous reduction of power consumption, a storage capacitor and a field-effect transistor are inserted in it, the gate of which is connected to one plate of the storage capacitor, the collector of the discharge transistor and through the first diode to the output of one of the secondary o6.vroTOK pulsed transformer, the other the secondary winding of which through the second diode is connected to the base of the discharge transistor, the emitter of which is connected to the second plate of the storage capacitor, the negative bus of the power source and the source a voltage transistor, the drain of which through an additional resistor is connected to the positive power supply bus. Sources of information taken into account during the examination 1. USSR author's certificate number 455485, cl. H 03 K 17 / 00.03.05.73. 2. USSR author's certificate JNo 448569, cl. H 03 H 7/38, 02.02.73. .6 /P i 7 o1 / 5