RU2798487C1 - Electronic direct-current voltage regulator - Google Patents

Abstract

FIELD: electrical engineering.

SUBSTANCE: method used in sources of secondary power supply for electronic equipment. The electronic direct-current voltage regulator contains a ballast resistor, a load, a regulating element, a rectifying voltage divider, a feedback divider. The control element contains a protective resistor and two MIS transistors with an integrated n-type channel. The rectifying voltage divider contains two resistors. The feedback divider contains two resistors and at least one pair of counter-connected avalanche stabilitrons of the same type.

EFFECT: increasing the reliability.

1 cl, 1 dwg

Description

The field of technology to which the invention belongs

The invention relates to the field of electrical engineering and can be used in sources of secondary power supply for electronic equipment.

State of the art

Known electronic DC voltage stabilizer (patent RU No. 2542673, IPC: G05F 1/569) containing: ballast resistor; load; equalizing voltage divider, made of two resistors connected in series; a feedback divider consisting of at least one zener diode connected in series and two resistors that form 2 arms, with at least one zener diode and a resistor forming one arm of the feedback divider, and the other arm constitutes the second resistor; a regulating element made of two bipolar transistors connected in series.

The disadvantage of this device are low reliability with limited functionality.

Low reliability is due to the implementation of the control element based on bipolar transistors, current-controlled devices, whose own energy consumption, and hence the thermal regime, is directly related to the magnitude of the switched current.

Limited functionality due to:

low temperature stability of the output voltage (narrow range of operating temperatures) in the case of a wide range of output voltages;

narrow range of output voltages with high temperature stability (wide operating temperature range).

The closest analogue - prototype to the claimed technical solution is an electronic DC voltage stabilizer (patent RU No. 162020, IPC: G05F 1/569).

Electronic DC voltage stabilizer contains: ballast resistor; load; an equalizing voltage divider made of two resistors connected in series, wherein its first output is the first output of the first resistor, the second output is the second output of the second resistor, the third output is the connection of the second output of the first resistor and the first output of the second resistor; a regulating element made of two series-connected npn type bipolar transistors, wherein the collector and base of the first npn type bipolar transistor serve as the first and third terminals of the regulating element, respectively, the emitter and base of the second npn type bipolar transistor serve as the second and fourth terminals, respectively a regulating element, and the emitter of the first npn type bipolar transistor is connected to the collector of the second npn type bipolar transistor; feedback divider, consisting of at least one pair of back-to-back (cathode to cathode) identical avalanche zener diodes connected in series, and two resistors that form two arms, the first resistor and at least one pair of back-to-back connected avalanche zener diodes of the same type form the first arm, and the second resistor forms the second arm, while the anode of the avalanche zener diode of the first pair of similar avalanche zener diodes, which serves as the first terminal of the first arm, is the first terminal of the feedback divider, the second terminals of the second arm and the feedback divider is the second terminal of the second resistor, the first the output of which and the second output of the first resistor connected to it serve, respectively, as the first and second outputs of the second and first arms, being, at the same time, the third output of the feedback divider, and the input of the negative polarity of the supply voltage of the stabilizer is connected to the second outputs of the equalizing voltage divider, control element, feedback divider, load, the first outputs of which are connected to the second output of the ballast resistor, the first output of which serves as the input of the positive polarity of the stabilizer supply voltage; the third output of the equalizing voltage divider is connected to the third output of the regulating element, the fourth output of which is connected to the third output of the feedback divider.

The disadvantage of this device is low reliability.

Disclosure of invention

The technical result that can be achieved using the present invention is to increase reliability.

The technical result is achieved by the fact that the electronic DC voltage stabilizer contains: a ballast resistor; load; regulating element; an equalizing voltage divider made of two resistors connected in series, wherein its first output is the first output of the first resistor, the second output is the second output of the second resistor, the third output is the connection of the second output of the first resistor and the first output of the second resistor; feedback divider, consisting of at least one pair of back-to-back (cathode to cathode) identical avalanche zener diodes connected in series, and two resistors that form two arms, the first resistor and at least one pair of back-to-back connected avalanche zener diodes of the same type form the first arm, and the second resistor forms the second arm, while the anode of the avalanche zener diode of the first pair of similar avalanche zener diodes, which serves as the first terminal of the first arm, is the first terminal of the feedback divider, the second terminals of the second arm and the feedback divider is the second terminal of the second resistor, the first the output of which and the second output of the first resistor connected to it serve, respectively, as the first and second outputs of the second and first arms, being, at the same time, the third output of the feedback divider, and the input of the negative polarity of the supply voltage of the stabilizer is connected to the second outputs of the equalizing voltage divider, control element, feedback divider, load, the first outputs of which are connected to the second output of the ballast resistor, the first output of which serves as the input of the positive polarity of the stabilizer supply voltage; the third output of the equalizing voltage divider is connected to the third output of the regulating element, the fourth output of which is connected to the third output of the feedback divider; which serves as the gate of the first MIS transistor with a built-in n -type channel, the second terminal of the protective resistor is connected to the drain of the first MIS transistor with a built-in n -type channel, the source of which is connected to the drain of the second MIS transistor with a built-in n -type channel, the source and gate of which serve , respectively, the second and fourth conclusions of the regulating element.

Brief description of the drawings

In FIG. a functional diagram of an electronic constant voltage stabilizer is presented.

Implementation of the invention

Electronic DC voltage stabilizer (Fig.) contains: ballast resistor 1; equalizing voltage divider 2, made of two series-connected resistors 3 and 4, while its first output is the first output of the resistor 3, the second output is the second output of the resistor 4, the third output is the connection of the second output of the resistor 3 and the first output of the resistor 4; control element 5, made using a protective resistor 6 and two MIS transistors with a built-in n -type channel 7 and 8, the first output of the protective resistor 6 serves as the first output of the regulating element 5, the third output of which is the gate of the MIS transistor with a built-in n -type channel 7 , the second output of the protective resistor 6 is connected to the drain of the MIS transistor with a built-in n -type channel 7, the source of which is connected to the drain of the MIS transistor with a built-in n -type channel 8, the source and gate of which serve, respectively, as the second and fourth outputs of the regulating element 5; feedback divider 9, consisting of at least one pair of back-to-back (cathode to cathode) identical avalanche zener diodes 10 and 11 (10.1÷10.n, 11.1÷11.n) connected in series, and two resistors 12, 13, which form two arms, and the resistor 12 and at least one pair of back-to-back identical avalanche zener diodes 10, 11 form the first arm, and the resistor 12 forms the second arm, while the anode of the avalanche zener diode 10.1, the first pair of the same type avalanche zener diodes 10.1, 11.1, serving as the first output of the first arm, is the first output of the feedback divider 9, the second outputs of the second arm and the feedback divider 9 is the second output of the resistor 13, the first output of which and the second output of the resistor 12 connected to it, serve, respectively, as the first and second outputs of the second and the first shoulders, being, at the same time, the third output of the feedback divider 9, the load 14, and the input of the negative polarity of the stabilizer supply voltage is connected to the second outputs of the equalizing voltage divider 2, the control element 5, the feedback divider 9, the load 14, the first outputs of which connected to the second output of the ballast resistor 1, the first output of which serves as the input of the positive polarity of the stabilizer supply voltage; the third output of the equalizing voltage divider 2 is connected to the third output of the regulating element 5, the fourth output of which is connected to the third output of the feedback divider 9.

Electronic DC voltage stabilizer works as follows.

An unstabilized voltage is supplied to the input terminals (+E, -E), which, through the ballast resistor 1, is supplied to the load 14, to the terminals of which three functional elements are connected in parallel:

leveling divider 2;

control element 5;

feedback divider 9.

, обеспечивающего заданные параметры напряжения на нагрузке 14, МДП транзисторы со встроенным каналом n-типа 7 и 8 находятся в режиме обогащения канала в приоткрытом состоянии, обеспечивая заданную величину проходного тока регулирующего элемента 5, а значит, выполнение условия (1)With an average value of the input voltage

, which provides the specified voltage parameters at the load 14, MIS transistors with a built-in n -type channel 7 and 8 are in the channel enrichment mode in the ajar state, providing a given value of the through current of the regulating element 5, which means that the condition (1)

, (1)

, (1)

напряжение на нагрузке 14,Where

load voltage 14,

сопротивление балластного резистора 1,

the resistance of the ballast resistor 1,

токи выравнивающего делителя 2, регулирующего элемента 5, делителя обратной связи 9, нагрузки 14.

currents of equalizing divider 2, regulating element 5, feedback divider 9, load 14.

This state of the control element 5 is provided by voltages coming from the third terminals (outputs) of the equalizing divider 2 and the feedback divider 9 to the gates of MIS transistors with an integrated n -type channel 7 and 8 of the control element 5.

The deviation of the input voltage from the average value of the voltage providing the specified parameters at the load 14 leads to a change in the output voltages of the equalizing divider 2 and the feedback divider 9.

If the input voltage deviates from the average value upwards, the output voltages of the equalizing divider 2 and the feedback divider 9 increase, the MIS transistors with the built-in n -type channel 7, 8 open slightly, which in turn causes an increase in the through current of the regulating element 5 and the execution condition (1).

If the input voltage deviates from the average value downwards, the output voltages of equalizing divider 2 and feedback divider 9 are reduced. MIS transistors with a built-in n -type channel 7, 8 are closed, which in turn causes a decrease in the through current of the regulating element 5 and the fulfillment of condition (1).

Used in the device, at least one pair of counter-connected avalanche zener diodes 10 and 11 of the same type provides mutual compensation of the temperature coefficients of the stabilization voltage of the zener diodes 10 and 11 (10.1 ÷ 10.n; 11.1 ÷ 11.n) and contributes to the expansion of the operating temperature range of the device , and output voltages.

In the case of the prototype, there is a relatively low efficiency. This is due to the implementation of the control element circuit 5 based on bipolar transistors. Since bipolar transistors are current-controlled devices, their own energy consumption, and hence the thermal regime, is directly related to the magnitude of the switched current. And an attempt to reduce the transistors' own power consumption (increasing the efficiency of the device) by using transistors with a lower base current (and therefore a lower allowable dissipation power will inevitably increase the requirements for increasing heat dissipation) will lead to a decrease in the reliability of the device.

At the same time, MOS transistors are characterized by a number of advantages over bipolar transistors (Oksner E.S. Powerful field-effect transistors and their application. - M .: Radio and communication, 1985, p. 19):

- voltage control (high resistance on the gate side, gate current is almost zero);

- high switching speed;

- almost unlimited output load capacity (if switching speed is not taken into account);

- very low probability of thermal self-heating;

- very low probability of secondary breakdown;

- the admissibility of a sharp change in the drain current.

This means that the proposed device, in the circuit of the regulating element 5 of which MIS transistors 7 and 8 are used, with the same value of the through current of the regulating element 5, as in the case of the prototype, will be characterized by a higher value of the coefficients of both efficiency and, above all, reliability.

An important contribution to improving both the reliability and efficiency of the proposed device is made by the fact that it is possible to use:

- high-resistance resistors as part of equalizing divider 2 and feedback divider 9;

- similar avalanche zener diodes 10 and 11 (10.1÷10.n; 11.1÷11.n) with low breakdown current,

since the control currents of the MIS transistors 7 and 8 are practically equal to zero.

The use of a protective resistor 6 in the circuit of the regulating element 5 improves both the reliability and the high voltage of the proposed electronic DC voltage stabilizer.

In addition, in the case of the prototype, there is a significant settling time of the output stabilized voltage, accompanied by a voltage jump at the load, and hence a decrease in the reliability of the load.

This is due to the fact that due to the serial connection of bipolar transistors, the time of direct bias of the emitter junctions increases significantly and the greater the base current (the greater the allowable dissipation power), the greater.

In the proposed device, MIS transistors with built-in n -type channel 7 and 8 are used, characterized by a normalized drain-source resistance in the absence of gate voltage. And hence the normalized value of the through current of the regulating element 5 at the moment of applying the input voltage. This reduces both the settling time of the output stabilized voltage and the amplitude of the voltage jump at the load, and hence the increase in load reliability.

Claims (1)

An electronic DC voltage stabilizer, comprising: a ballast resistor; load; regulating element; an equalizing voltage divider made of two resistors connected in series, wherein its first output is the first output of the first resistor, the second output is the second output of the second resistor, the third output is the connection of the second output of the first resistor and the first output of the second resistor; a feedback divider consisting of at least one pair of back-to-back cathode-to-cathode identical avalanche zener diodes and two resistors connected in series, which form two arms, the first resistor and at least one pair of back-to-back connected avalanche zener diodes of the same type forming the first arm, and the second the resistor forms the second arm, while the anode of the avalanche zener diode of the first pair of similar avalanche zener diodes, which serves as the first terminal of the first arm, is the first terminal of the feedback divider, the second terminals of the second arm and the feedback divider is the second terminal of the second resistor, the first terminal of which is connected to it the second output of the first resistor serve, respectively, as the first and second outputs of the second and first arms, being, at the same time, the third output of the feedback divider, and the input of the negative polarity of the stabilizer supply voltage is connected to the second outputs of the equalizing voltage divider, the regulating element, the feedback divider, loads, the first outputs of which are connected to the second output of the ballast resistor, the first output of which serves as the input of the positive polarity of the stabilizer supply voltage; the third output of the equalizing voltage divider is connected to the third output of the regulating element, the fourth output of which is connected to the third output of the feedback divider, characterized in that the following is introduced into the device: a protective resistor, two MOS transistors with an integrated n -type channel, the first output of the protective resistor serves the first output of the regulating element, the third output of which is the gate of the first MIS transistor with a built-in n -type channel, the second output of the protective resistor is connected to the drain of the first MIS transistor with a built-in n -type channel, the source of which is connected to the drain of the second MIS transistor with a built-in an n -type channel, the source and gate of which serve, respectively, as the second and fourth outputs of the regulating element.

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