SU1334128A2 - Stabilized power source - Google Patents

Abstract

The invention relates to electrical engineering, namely to power supply systems for electronic equipment. The purpose of the invention is to increase the reliability of the power source. The circuit is reached by the fact that the emitter of the transistor 23 of the self-holding cascade is connected to the negative bus of the primary power supply via the current generator 25. This improves the reliability, because at the moment of power-up and transients on the power supply circuit, the transistor 23 of the self-holding cascade is locked by a voltage on the resistor 24, created by the current generator 25. 1 Il. (Lk)

Description

The invention relates to electrical engineering, in particular, to power supply systems for electronic and electronic automation and computer technology based on DC voltage regulators.

The purpose of the invention is to increase reliability by eliminating the spontaneous actuation of an overvoltage protection node during power up and transients along the power supply circuit.

The drawing shows a functional diagram of the proposed stabilized power source.

I

Stable power supply

contains input pins 1 and 2 and output pins 3 and 4, of which pins I and 3 are positive, and pins 2 and 4 are minus buses, stabilizer 5 constant voltage with res-. i'm guilting one element 6 of the sequential type, included in the plus EGinu. The stabilizer 5 also includes a resistive current sensor 7, a resistive sensor 8 of the output voltage of the source, an element 9 of the reference voltage and an amplifier 10 of the error signal, consisting of a differential amplifier 5 of the matching transistor cascade and a transistor current protection cascade. Functional blocks 9 and 10 are combined in a single integrated circuit like 142EN1, 42EN2, or 42EIZ. The source also contains a node 11 of the surge voltage at the source output with a protective transistor 12 connected between the input supply terminal 1 of the source and the input terminal (not labeled) of the stabilizer 5. The protection node 11 also includes a differential gain on transistors 13, 14 , 15 with a blocking transistor 16, a voltage reference element on transistors 17 and 18, and a zener diode 19, an individual resistive sensor 20 of the output voltage of the source, a matching cascade on transistors 21 and 22, and a self-holding cascade on transistor 23. Opo The differential input of the amplifier (control input of transistor 13) is connected to the output of the reference voltage element (with the emitter load of transistor 18), and sigv: the main input (control input of transistor 14) with the output of sensor 20 of the output voltage wives

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source. A matching stage in transistors 2 and 22 is connected between the output of the differential amplifier (collector load of transistor 14) and the base of the protective transistor 12. The differential amplifier, the reference voltage element and the matching transistor stage are also combined in another integrated circuit 142EN1 or 142EN2. The emitter-collector junction of the transistor 23 of the self-holding cascade is connected between the input supply terminal 1 of the source through the resistor 24 and the input of the blocking transistor of the differential amplifier (the base circuit of transistor 16), and the control input of this cascade (emitter-base transition of the transistor 23) is connected the output of the latter (with the collector load of the transistor 14). The emitter of transistor 23 is connected to negative bus 2 via a current generator (resistor) 25.

The device works as follows.

In the error signal amplifier 10, the voltages coming from the outputs of the sensor 8 of the output voltage of the source and the element 9 of the reference voltage are compared. When the source voltage changes, a difference signal appears, which is amplified by amplifier 10 and fed to the control input of the regulating element 6. Changing the signal at the control input of the regulating element 6 causes the voltage drop on it, resulting in a voltage the source output returns to its original value with a certain degree of accuracy, which is a technical indicator of a constant voltage stabilizer 5.

The source of over-current and short-circuit protection at its output is protected with the help of a current sensor 7 and the error signal of the transistor cascade of the current protection included in the amplifier 10, which detects an excessive increase in the current from the sensor 7 output current.

The protection node 11 performs the functions of surge protection at the source output. If an overvoltage occurs at the outputs 3 and 4, for example, in the case of the breakdown of the regulating element 6 of the stabilizer 5 post3

voltage, the output signal of the source output voltage sensor 20 is increased. Thus, the signal at the signal input of the differential amplifier (at the control input of transistor 14) increases above the level of the reference voltage supplied to the reference input of the differential amplifier (at the control input of transistor 13) from the output of the reference voltage element (from the emitter load of the transistor 18). As a result, the transistor 14 is opened, and the transistor 21 and 22 of the matching cascade and the protective transistor 12 are closed. At the same time, the signal from the output of the differential amplifier (from the collector load of transistor 14) passes into the saturation state of the transistor 23 of the self-control stage and connects the input supply terminal 1 of the source to the input of the blocking transistor of the differential amplifier (with the base circuit of transistor 16). The transistor 16 opens and transmits the locking potential to the control input of the matching stage at the transistors 21 and 22.

In this case, the protection transistor 12 is latched, i.e. remains in the closed state, despite the fact that, due to the subsequent decrease in voltage at the source output, the level is reduced. Editor M.Tovtin Order 3962/45

Compiled by S.Gorbacheva Tehred I.Popovich

Proofreader L.

Circulation 863 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company Uzhgorod, st. Project, 4

five

0

five

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The yarn output of sensor 20 and the signal input of the differential amplifier are again below the voltage level at its reference input.

The stability of the stablizer as compared with the prototype is achieved by the fact that at the time of power-up and transients along the power supply circuit, the self-holding cascade 23 is locked by a voltage across the resistor 24 created by the current generator 25. With a small change in the voltage of the stabilizer instead of the generator current is possible to use a resistor. In addition, the noise immunity of the device by eliminating the spontaneous actuation of the overvoltage protection node during power-up and transients in the power supply circuit.

Claims (1)

Invention Formula Stabilized power source by author. St. No. 1103213, characterized in that, in order to increase reliability by eliminating the spontaneous actuation of the overvoltage protection unit during power-up and transients in the power supply circuit, the emitter of the self-holding cascade transistor is connected to the negative bus through an inserted current generator. Proofreader L. Pilipenko