SU830369A2

SU830369A2 - Dc voltage limiter

Info

Publication number: SU830369A2
Application number: SU792798881A
Authority: SU
Inventors: Алексей Иванович Селиванов; Вячеслав Андреевич Логинов
Original assignee: Предприятие П/Я А-3526
Priority date: 1979-07-16
Filing date: 1979-07-16
Publication date: 1981-05-15

Description

Изобретение относится к электротехнике и может быть использовано для защиты полупроводниковой аппаратуры и вторичных источников электропитания от бросков напряжения, возникающих _; в сети постоянного тока.The invention relates to electrical engineering and can be used to protect semiconductor equipment and secondary power supplies from power surges that occur _; in a direct current network.

По основному авт. св. № 602932 известно устройство, используемое преимущественно в сети постоянного тока для ограничения напряжения, содержащее ограничительный резистор, подклюй ценный к одному из входных выводов, шунтирующий транзистор, переходом коллектор-эмиттер подключенный к выходным выводам, а базой через ставили— _}затор к точке соединения второго вывода ограничительного резистора с коллектором второго транзистора, эмиттер которого соединен с одним из выходных выводов, а база к средней точке после— ₂довательной цепочки из стабилитрона и резистора, подключенных к общей шине к коллектору второго транзистора соответственно Г11.According to the main author. St. № 602 932 discloses a device, advantageously used in a DC network for limiting the voltage, comprising: limiting resistor, podklyuy valuable to one of the input terminals, the shunt transistor, the collector-emitter connected to the output terminals and the base through _stavili-} congestion point to the second compound O-limiting resistor to the collector of the second transistor, the emitter of which is connected with one of output terminals, and base to an intermediate point ₂ sive post-chains of the zener diode and resistor at connected to the common bus to the collector of the second transistor, respectively, G11.

Недостатком данного устройствам является низкая чувствительность, вследствие чего устройство срабатывает только от бросков напри жения источника электропитания достаточно большой величины, а это может привести к выходу из строя полупроводниковой аппаратуры или вторичного источника электропитания. (чувствительных к низким уровням перенапряжения), подключенных в качестве нагрузки.The disadvantage of this device is its low sensitivity, as a result of which the device is only triggered by surges of a power source of a sufficiently large magnitude, and this can lead to failure of semiconductor equipment or a secondary power source. (sensitive to low overvoltage) connected as load.

Цель изобретения - повышение чувствительности устройства при бросках напряжения источника электропитания.The purpose of the invention is to increase the sensitivity of the device during power surges.

Эта цель достигается тем, что в ограничитель постоянного напряжения введены первый дополнительный транзистор проводимости р - η - р, второй дополнительный транзистор проводимости П - р - два резистора и конденсатор, причем эмиттер первого дополнительного транзистора соединен с точкой соединения Входного вывода с ограничительным резистором, база подключена к другому выводу ограничительного резистора и одной обкладке конденсатора, а коллектор этого транзистора через первый дополнительный резистор к базе второго дополнительного транзистора и одному выводу второго дополнительного резистора, коллектор второго дополнительного транзистора соединен с катодом стабилитро- на, расположенного в цепи 'формирования управляющего напряжения, а эмиттер второго дополнительного транзистора подключен к общей шине, которая соединена с другой обкладкой конденсатора и другим выводом второго дополнительного резистора. .This goal is achieved by the fact that the first additional conductivity transistor p - η - p is introduced into the DC voltage limiter, the second additional conductivity transistor P - p - two resistors and a capacitor, and the emitter of the first additional transistor is connected to the input connection point with the limiting resistor, base connected to another terminal of the limiting resistor and one capacitor plate, and the collector of this transistor through the first additional resistor to the base of the second additional trans ora and one terminal of the second additional resistor, the collector of the second additional transistor is connected to the cathode on stabilitro- located in the chain 'generating the control voltage, and an emitter of the second transistor is further connected to a common bus which is connected to the other plate of the capacitor and the other terminal of the second additional resistor. .

На чертеже изображена принципиальная электрическая схема устройства.The drawing shows a circuit diagram of a device.

Схема ограничителя постоянного . напряжения содержит ограничительный резистор 1, защитный транзистор 2, шунтирующий транзистор 3, цепь формирования управляющего напряжения, состоящую из резистора 4 и стабилитрона 5, ограничительный стабилитрон 6, первый дополнительный транзистор 7, второй дополнительный транзистор 8, конденсатор 9 и два дополнительных резистора 1О и 11.Constant limiter circuit. The voltage contains a limiting resistor 1, a protective transistor 2, a shunt transistor 3, a control voltage generating circuit consisting of a resistor 4 and a zener diode 5, a limiting zener diode 6, a first additional transistor 7, a second additional transistor 8, a capacitor 9, and two additional resistors 1O and 11 .

Ограничитель постоянного напряжения работает следующим образом.The DC voltage limiter operates as follows.

При отсутствии бросков напряжения в цепи источника электропитания защитный транзистор 2 открыт, транзисторы 3, 7 и 8 закрыты, конденсатор 9 заряжен до напряжения источника электропитания. При бросках напряжения в цепи транзистор 7 отпирается вследствие увеличения падения напряжения на ограничительном резисторе 1, которое подается через конденсатор 9, транзистор· 8 также отпирается, вследствие увеличения напряжения, подаваемого на переход база-эмиттер, этого транзистора с резистора 11, и ^zсвоим переходом коллектор-эмиттер шунтирует стабилитрон 5, что приводит к увеличению падения напряжения на резисторе 4 и повышению эффективности запирания защитного транзистора 2 и отпирания шунтирующего транзистора 3. ₅ Изобретение позволяет повысить чувствительность защиты полупроводниковой аппаратуры от бросков питающего напряжения, что повышает надежность ее работы.In the absence of voltage surges in the circuit of the power source, the protective transistor 2 is open, the transistors 3, 7 and 8 are closed, the capacitor 9 is charged to the voltage of the power source. When surges in the circuit, the transistor 7 is unlocked due to the increase in the voltage drop across the limiting resistor 1, which is supplied through the capacitor 9, the transistor · 8 is also unlocked, due to the increase in the voltage supplied to the base-emitter junction of this transistor from the resistor 11, and ^z the collector-emitter shunts the zener diode 5, which leads to an increase in the voltage drop across the resistor 4 and an increase in the efficiency of locking the protective transistor 2 and unlocking the shunt transistor 3. ₅ The invention allows It increases the sensitivity of protection of semiconductor equipment against surges of the supply voltage, which increases the reliability of its operation.

Claims

The invention relates to electrical engineering and can be used for semiconductor equipment and secondary power sources against surges arising in a DC network. According to the main author. St. No. 6O2932, a device used predominantly in a DC network for limiting voltage, containing a limiting resistor connected to one of the input pins, a shunting transistor, a collector-adapter junction connected to the output pins, and the base through the stabilizer to the point connecting the second terminal of the limiting resistor to the collector of the second transistor, the emitter of which. connected to one of the output pins, and the base to the midpoint of the series chain of the Zener diode and the resistor connected to the common busbar to the collector of the second .trananstar respectively Til. The disadvantage of this device is that the sensitivity is low, as a result of which the device only triggers from surges in the power supply source of a sufficiently large value, and this can lead to the failure of the semiconductor equipment or the secondary power supply (sensitive to low levels of overvoltage) connected as a load. The purpose of the invention is to increase the sensitivity of the device when the power supply voltage surges. This goal is achieved by introducing the first additional conductive transistor p - n - p into the constant voltage limiter, the second additional conductive transistor 1 - p -) 1 two resistors and a capacitor, and the emitt of the first additional granzist1 {: output with a limiting resistor, the base is connected to another input of the limiting resistor and the coil of the resistor, and the collector of this transistor through the first additional resistor to the base of the second additional transistor The second additional additional resistor is connected to the cathode of the stabilizer located in the control circuit of the control board, and the emitter of the second additional transistor is connected to a common bus that is connected to the other side of the second resistor. . . The drawing shows a circuit diagram of the device. Permanent limiter scheme. For example, the capacitor 1 contains a limiting resistor 1, a protective transistor 2, a suppressor transistor 3, a form of a control voltage K), consisting of a resistor 4 and a zener diode 5, a limiting zener diode 6, a first additional transistor 7, a second additional transistor 8, a capacitor 9 and Two additional resistors 1O and 11 A constant voltage limiter operates as follows. In the absence of voltage surges in the power supply circuit, the protection transistor 2 is open, the transistor 3 7 and 8 are closed, the capacitor 9 is charged before the voltage of the power supply. During voltage surges in the circuit, the transistor 7 is unlocked due to an increase in the voltage drop across the limiting resistor 1, which is fed through the capacitor 9, the transistor 8 also unlocks, due to the increase in the voltage applied to the base-emitter junction of the transistor 11, and with its junction, the collector-emitter shunts Zener diode 5, which leads to an increase in the voltage drop across resistor 4 and an increase in the efficiency of locking the protective transistor 2 and unlocking the shunt transistor 3, It does not increase the sensitivity of semiconductor equipment protection against overvoltage, which increases the reliability of its operation. Claims of a constant voltage limiter according to the ed. St. No. 6O2932, characterized in that, in order to increase the sensitivity, a first additional conductivity transistor P - n - p, a second additional conductivity transistor rn-L, two resistors and a capacitor are inserted into it, the emitter of the first additional transistor is connected to a point input terminal connections with a limiting resistor, the base is connected to another Output of the limiting resistor and one capacitor plate, and the collector of this transistor through the first additional resistor to the base of the second additional terminal anisistor and one output of the second additional resistor, the collector of the second additional transistor is connected to the cathode of the Zener diode located in the control voltage circuit, and the emitter of the second additional transistor is connected to the common busbar and another output of the second additional resistor. Sources of information taken into account during the examination 1. USSR author's certificate No. 6O2932, cl. G OS F 3 / O8, 1978.

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