CN212992203U

CN212992203U - Boost circuit

Info

Publication number: CN212992203U
Application number: CN202021847973.6U
Authority: CN
Inventors: 张经宇; 陈哨东
Original assignee: Luoyang Institute of Electro Optical Equipment AVIC
Current assignee: Luoyang Institute of Electro Optical Equipment AVIC
Priority date: 2019-10-16
Filing date: 2020-08-27
Publication date: 2021-04-16
Anticipated expiration: 2030-08-27
Also published as: CN110649807A

Abstract

A boost circuit comprises a timer 555 circuit, a push-pull switch circuit, a 3.3V logic level change reference circuit, a micro power inductor, an output diode, a protection circuit and an output interface; the timer 555 circuit is connected with the push-pull switch circuit; the push-pull switch circuit is connected with the micro power inductor; the 3.3V logic level conversion reference circuit is connected with the protection circuit; the input voltage, the miniature power inductor, the output diode, the protection circuit and the output interface are sequentially connected. The utility model discloses a timer 555 designs boost circuit, realizes on hardware, does not need software to participate in, occupies PCB area is less than 2cm²The height is less than 2mm, the I0 port of the device such as the singlechip, the CPLD and the like controls the output interface module at the high-voltage side, the circuit is reliable, and the speed can reach the mu s level. When the peripheral load circuit has short circuit and overload, the output interface module can be disconnected to protect the boost circuit.

Description

Boost circuit

Technical Field

The utility model belongs to the technical field of the electron, concretely relates to boost circuit.

Background

In recent years, with rapid development of power industries such as photovoltaic power generation, ultrahigh voltage transmission and the like, more and more power supplies in an ultra-wide input range are required, but the existing booster circuit generally has the defects of large volume, high cost, complex circuit, large interference, low reliability and the like.

In the prior art, for a power supply with an ultra-wide input range, a boost circuit is added at the front stage of a single-machine power converter, as shown in fig. 3, the basic circuit of the boost circuit is assumed that Q1 is turned off for a long time, all elements are in an ideal state, and the capacitor voltage is equal to the input voltage. When the charging process is started, Q1 is closed, and an equivalent circuit is shown in FIG. 4; when the discharging process is started, the Q1 is disconnected, the equivalent circuit is as shown in fig. 5, when the Q1 is disconnected, the current flowing through the inductor does not immediately become 0 due to the current holding characteristic of the inductor, but slowly changes from the value at the time of charging to 0, the original circuit Q1 is disconnected, and then the inductor can only discharge through the new circuit, namely, the inductor starts to discharge to the capacitor, the voltage at two ends of the capacitor rises, and at the moment, the voltage is higher than the input voltage, and the boosting is finished.

When designing the boost circuit, a proper MOS transistor driving circuit, a related logic control circuit, and the like need to be selected.

SUMMERY OF THE UTILITY MODEL

Utility model purpose:

an object of the utility model is to provide a boss boost circuit for the high-end MOS pipe of actuating system.

The technical scheme is as follows:

a boost circuit comprises a timer 555 circuit, a push-pull switch circuit, a 3.3V logic level change reference circuit, a micro power inductor, an output diode, a protection circuit and an output interface;

the timer 555 circuit is connected with the push-pull switch circuit;

the push-pull switch circuit is connected with the micro power inductor;

the 3.3V logic level conversion reference circuit is connected with the protection circuit;

the input voltage, the miniature power inductor, the output diode, the protection circuit and the output interface are sequentially connected.

Based on the design of the timer 555, milliampere driving current uses small inductance, except the timer 555, the milliampere driving current is formed by small packaged discrete elements, the voltage is adjustable, the output of the booster circuit can be controlled by logic level, and the milliampere driving current can be conveniently used as a system high-end side MOS tube turn-off driving source.

Further, the timer 555 circuit is used for generating adjustable pulses to control the operation of the push-pull switch circuit.

Furthermore, the push-pull switch circuit and the miniature power inductor form a basic boost circuit for boosting the input voltage.

Further, the 3.3V logic level change reference circuit is used for controlling the off end and the conduction of the circuit.

Further, the output diode is used for ensuring the output direction of the voltage.

Furthermore, the protection circuit is used for limiting the input range of the input voltage and playing a protection role.

Has the advantages that:

the utility model discloses a timer 555 designs boost circuit, realizes on hardware, does not need software to participate in, occupies that the PCB area is less than 2cm²The height is less than 2mm, the I0 port of the device such as the singlechip, the CPLD and the like controls the output interface module at the high-voltage side, the circuit is reliable, and the speed can reach the mu s level. When the peripheral load circuit has short circuit and overload, the output interface module can be disconnected to protect the boost circuit.

Drawings

Fig. 1 is a schematic block diagram of a boost circuit provided by the present invention;

FIG. 2 is a schematic diagram of a boost circuit provided by the present invention;

FIG. 3, basic boost circuit;

FIG. 4 is an equivalent circuit of the boost circuit charging process;

fig. 5 shows an equivalent circuit of the discharge process of the boost circuit.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings:

as shown in fig. 3, which is the basic circuit of the boost circuit, assuming that Q1 has been off for a long time, all elements are in an ideal state, and the capacitor voltage is equal to the input voltage. When the charging process is started, Q1 is closed, and an equivalent circuit is shown in FIG. 4; when the discharging process is started, the Q1 is disconnected, the equivalent circuit is as shown in fig. 5, when the Q1 is disconnected, the current flowing through the inductor does not immediately become 0 due to the current holding characteristic of the inductor, but slowly changes from the value at the time of charging to 0, the original circuit Q1 is disconnected, and then the inductor can only discharge through the new circuit, namely, the inductor starts to discharge to the capacitor, the voltage at two ends of the capacitor rises, and at the moment, the voltage is higher than the input voltage, and the boosting is finished.

Examples

As shown in fig. 1, for the schematic block diagram of the boost circuit provided by the present invention,

the circuit comprises a timer 555 circuit, a push-pull switch circuit, a 3.3V logic level change reference circuit, a micro power inductor, an output diode, a protection circuit and an output interface;

the timer 555 circuit is connected with the push-pull switch circuit;

the push-pull switch circuit is connected with the micro power inductor;

the input voltage, the miniature power inductor, the output diode and the protection circuit are sequentially connected with the output interface;

the high voltage input signal is input to the power inductor through the diode, then to the output diode, and then to the output circuit and its protection circuit through the output diode, the timer 555 integrated circuit sends PWM wave with 50% pulse width and 5KHz frequency, the PWM wave can set frequency and duty ratio by adjusting the resistance-capacitance device on the periphery, achieves the purpose of regulating voltage. Because the 3.3V logic level voltage sent by the singlechip or the CPLD is very low, the boost circuit cannot be directly controlled, and the output of the output circuit is generally high level of about 100V, the singlechip or the CPLD sends out the logic control level and needs to control the output of the boost circuit through the logic level boost circuit. The circuit is provided with a perfect protection circuit, and the control speed only depends on the I/O speed of a single chip microcomputer or a CPLD. The cost is very low, the height is very low, and the device is suitable for occasions with limited space and volume.

As shown in fig. 2, the boost circuit schematic diagram provided by the present invention is shown. U31 is timer 555 circuit, and the third foot of 555 integrated circuit output PWM signal, this PWM signal drive Q134 and Q135 constitute the push-pull switch circuit, and wherein C92 electric capacity connects the input voltage, plays the effect of isolation direct current.

L2 is a miniature power inductor with inductance of 1mH, C116 isolates direct current again, D78 is a double diode which plays both output and protection roles, D80 is a voltage stabilizing diode which selects types according to output voltage, and Q151, Q152, Q153, Q154, Q155 and peripheral resistance-capacitance devices form a logic booster circuit for controlling output of logic level.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. A boost circuit is characterized in that the circuit comprises a timer 555 circuit, a push-pull switch circuit, a 3.3V logic level change reference circuit, a micro power inductor, an output diode, a protection circuit and an output interface;

the timer 555 circuit is connected with the push-pull switch circuit;

the push-pull switch circuit is connected with the micro power inductor;

the input voltage of the boost circuit is sequentially connected with the micro power inductor, the output diode, the protection circuit and the output interface.

2. The circuit of claim 1, wherein the timer 555 circuit is configured to generate adjustable pulses to control operation of the push-pull switching circuit.

3. The circuit of claim 1, wherein the push-pull switch circuit and the micro power inductor form a basic boost circuit for boosting an input voltage.

4. The circuit of claim 1, wherein the 3.3V logic level change reference circuit is configured to control the circuit to be off and on.

5. The circuit of claim 1, wherein the output diode is configured to ensure an output direction of the voltage.

6. The circuit of claim 1, wherein the protection circuit is configured to limit an input range of the input voltage for protection.