SU1406578A1 - D.c. voltage stabilized converter - Google Patents

Abstract

The invention relates to secondary power sources. The aim of the invention is to increase the reliability of starting over a wide range of input voltages. The goal is achieved by the fact that the first valve 5, key 6, bias source 7, prohibition element 8, stabilized one-shot 9, second valve 10, and time setting element 11 are entered into the circuit. at the output, as well as switching on the riffOff of the power supply through the bias source 7 and the open prohibition element 8, a single vibrator 9 is started, the output pulses of which provide the flow through the key 6, the input voltage is controlled, the voltage applied to the power input of the pulse pulse modulator ( PWM) 4. The output current is limited in the short circuit mode and when turned on by the signal from the current sensor 3. The key 6 does not pass a voltage below the certain threshold to the output, and passes the voltage above this threshold completely, without subtracting the threshold -, in go voltage This provides the PWM 4 with a stable voltage in the startup modes, which increases its reliability over a wide range of input voltages. After the nominal output voltage is established, the power supply to the SHW is carried out through the first valve 5, and the operation of the one-shot 9 is blocked by the prohibition element 8 through time the setting element 11. 1 sludge. dx s (L S 4 o O) cd 5

Description

: The invention relates to electrical engineering, in particular, to devices for converting a constant voltage of one magnitude into a constant voltage of another magnitude, and can: be used when designing a scientific research institute of secondary power sources. (VIP) for electronic equipment- i.

I The purpose of the invention is to increase the reliability of the start-up over a wide range of input voltages, I The drawing shows a functional diagram of a stabilized converter made according to this invention.

{Stabilized constant-voltage converter I contains the constant-voltage I I-to-pulse conversion unit I 1, the reverse I conversion unit 2, the current sensor 3 in the power circuit, the pulse-width modulator I l tor (PWM) 4 , as well as the first valve i-5, the key 6, the control voltage on: its input, the source 7 bias, the prohibition element 8, the stabilizing one novibrator 9, the second valve 10 and the time setting element 11.

Stabilized Converter works as follows.

When the supply voltage is switched on, the voltage of the bias source 7 through the open inhibitor element 8 is fed to the input of the one-shot and start-up; its Single-Vibrator 9 generates a single pulse of stabilized voltage, approximately equal to the output voltage of the converter, which; via key 6 enters the PWM power input, the pulse duration; to be sufficient to complete; transient switching on of the converter and the establishment of a stabilized voltage at its output. This voltage is regulated and stabilized by a feedback circuit through the first BAT control input. At the end of the startup pulse, in the steady state, the PWM converter is powered from the converter output via the first gate 5 and the key 6.

The voltage from the output of the converter through the first 5 and second 10 valves and the time of the driver element 11 is fed to the control: the input of the prohibition element 8. This stops the supply of bias voltage to the input of the one-shot 9, which is locked at all times of the steady-state retkim.

Current sensor 5 continuously monitors the load current of the converter.

When an overload voltage from the sensor exceeds the threshold voltage of the incoming, its composition of the threshold element and is fed to the second control input of the PWM, the converter switches to the stabilization mode (limitation) of the maximum load current "The voltage at the output of the converter decreases while short circuit load drops to zero „

The overload and short-circuit modes themselves, when there is a maximum load current limit for the converter, are perfectly safe for any length of time, since the maximum load current is limited to 1 the same level as the critical S driving key transistors from saturation. The under-excited mode of operation of the key transistors of the conversion unit, which can occur when the PWM is powered by a low voltage from the output of the overloaded converter, is dangerous. To prevent the under-excited mode of operation of the conversion unit, a switch 6 is used, which is controlled by the input voltage and is characterized in that it does not pass a voltage below a certain threshold to the output, and passes a voltage above this threshold completely without subtracting the threshold voltage. Due to this, the low voltage from the output of the converter during overloads to the PWM power input is not supplied and the converter switches off. After the time determined by the timing element 11, the voltage is removed from the control input of the prohibition element B, the bias voltage is again applied to the input of the one-oscillator

9 and a new startup process begins. If the overload is not eliminated, test runs will be repeated at intervals determined by the time of the setting element 11.

Thus, powering the PWM from the output of the converter ensures its high efficiency, and the formation of stabilized starting pulses ensures a steady start on switching on and after elimination of the overload.

in a wide range

SRI.

input signals

formula and invention

A stabilized DC-DC converter containing a series of voltage-to-pulse voltage conversion unit and a reverse voltage conversion unit and a reverse conversion unit, a current sensor in the power circuit, a pulse-width modulator with a power input, the output of which is connected to the control unit. A constant voltage-to-voltage conversion unit input, a first control input to an output terminal, and a second control input to a current sensor output, characterized in that

In order to increase start-up reliability in a wide range of input voltages, a first valve, a key controlled by an input voltage, and a series-connected bias source, a prohibition element, a stabilized one-shot, a second valve, and a master element are inputted into it; the element is connected to the control input of the prohibition element, the output of the stabilized one-vibrator is connected to the key input and through the first valve to the output output, the output of the key is connected to the power input of the pulse-width modulator, s input offset source input power stabilized monostable connected to the input terminal.

Claims (1)

Formula of the invention $ A stabilized DC-DC converter containing a unit for converting a constant voltage into a pulse-jq pulse and an inverse conversion unit, a current sensor in a power circuit, a pulse-width modulator with a power input, the output of which is connected to a control input, connected in series between input and output terminals unit for converting direct voltage to pulse, the first control input to the output terminal, and the second control input to the output of the current sensor, characterized in that oh, in order to increase the reliability of starting in a wide range of input voltages, the first valve, a key controlled by the input voltage, and the bias source, the inhibit element (stabilized one-shot, the second valve and the timing element, the output of the timing element j that is connected to the control input of the inhibit element, the output of the stabilized one-shot to the key input and through the first valve to the output 15 output, the key output to the power input of the pulse-width module ¹ - torus a, and the input of the bias source and the power input of the stabilized one-shot are connected to the input 20 output.