WO2018192081A1

WO2018192081A1 - Voltage stabilizing circuit and power supply circuit and remote control having same

Info

Publication number: WO2018192081A1
Application number: PCT/CN2017/088339
Authority: WO
Inventors: 叶勇云
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2017-04-19
Filing date: 2017-07-04
Publication date: 2018-10-25
Also published as: CN206726080U; CN109804327A; CN109804327B

Abstract

Provided are a voltage stabilizing circuit (100) and a power supply circuit and a remote control having the voltage stabilizing circuit (100). The voltage stabilizing circuit (100) comprises a controller (1); at least two transistors (Q1, Q2); and current equalization resistors (R1, R2) correspondingly connected in series with emitter electrodes of the respective transistors (Q1, Q2). The at least two transistors (Q1, Q2) are connected in parallel. For the at least two transistors (Q1, Q2) connected in parallel, base electrodes thereof are connected to a control end of the controller (1), and the emitter electrodes thereof are connected to an input power supply (Vcc). Moreover, collectors of the at least two transistors (Q1, Q2) connected in parallel are connected to a back-end hardware module (3). The power supply circuit can realize current equalization of the transistors (Q1, Q2) and output a stabilized voltage.

Description

Voltage stabilizing circuit and power supply circuit and remote controller having the same

Technical field

The present invention relates to the field of electronic circuits, and in particular, to a voltage stabilizing circuit, a power supply circuit having the same, and a remote controller.

Background technique

At present, LDO (low dropout regulator) circuit is widely used as a voltage regulator circuit. The existing LDO circuits are divided into two types, one is a chip integrated with an LDO controller and a triode, and the other is an integrated LDO controller in the chip, but the triode is not integrated in the chip, and the user needs an external triode. The LDO function is realized by the cooperation of the LDO controller and the triode.

In an LDO circuit that requires an external transistor, there may be cases where a single transistor cannot meet the performance requirements. For example, if the rated current of the voltage regulator circuit is insufficient, multiple (at least two) transistors need to be connected in parallel to meet the current demand of the voltage regulator circuit. . If only a small number of triodes are simply connected in parallel, it may be due to the difference of each triode itself, temperature changes and other factors, resulting in a difference in current flowing through the triodes after parallel connection. In extreme cases, some triodes may flow through. The current is very small, and some of the currents flowing through the triodes are large or even exceed their rated currents. After a long time of operation, the triode damage may occur, which may affect the service life of the LDO circuit.

Summary of the invention

The invention provides a voltage stabilizing circuit and a power supply circuit and a remote controller having the same.

Specifically, the present invention is achieved by the following technical solutions:

According to a first aspect of the present invention, a voltage stabilizing circuit includes a controller, at least two transistors, and a current sharing resistor corresponding to an emitter connected in series to each of the transistors, wherein at least two of the transistors are connected in parallel, The bases of at least two of the parallel transistors are connected to the control terminal of the controller, the emitters are connected to the input power source, and the collectors of the at least two of the parallel transistors are connected to the back end hardware modules.

Optionally, the emitters of the at least two of the transistors are connected in series with equal current resistance values.

Optionally, the controller is an LDO controller, the LDO controller includes a signal detecting unit, and the signal detecting unit is configured to detect the base or collector of the at least two transistors after the parallel connection signal.

Optionally, the voltage stabilizing circuit further includes a feedback circuit, configured to detect signals on the base or collector of the at least two of the parallel transistors, and send the detected signals to the control Device

An input end of the feedback circuit is connected to a base or a collector of at least two of the parallel transistors, and an output end of the feedback circuit is connected to the controller.

Optionally, the feedback circuit includes a comparator, an input end of the comparator is connected to a base or a collector of at least two of the parallel transistors, and an output of the comparator is connected to the controller .

Optionally, a grounded first capacitor is further connected between the input power source and the emitters of the parallel connected at least two of the transistors.

Optionally, the collectors of the at least two of the transistors are connected to a grounded second capacitor.

Optionally, at least two of the transistors are PNPs.

According to a second aspect of the present invention, there is provided a power supply circuit comprising an input power source and the voltage stabilizing circuit, the voltage stabilizing circuit being coupled to the input power source.

According to a third aspect of the present invention, a remote controller includes a back end hardware module and the power supply circuit, and the power supply circuit is coupled to the back end hardware module.

As can be seen from the technical solutions provided by the embodiments of the present invention, the present invention reduces the current flowing through each of the transistors by equalizing the series current sharing resistors of the emitters of each of the parallel transistors, thereby reducing at least two transistors in parallel. The occurrence of a circuit excess occurs, ensuring the life of the triode, and finally ensuring the life of the device having the voltage stabilizing circuit; and, by the cooperation of the controller and the at least two transistors in parallel, the set of at least two of the triodes after the parallel connection The output voltage of the electrode is maintained at the required voltage level to provide stable power supply to the back-end hardware modules.

The above general description and the following detailed description are intended to be illustrative and not restrictive.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. Other drawings may also be obtained from those of ordinary skill in the art in view of the drawings.

1 is a schematic structural diagram of a voltage stabilizing circuit according to an embodiment of the present invention;

2 is a schematic structural diagram of another voltage stabilizing circuit according to Embodiment 1 of the present invention;

3 is a schematic structural diagram of still another voltage stabilizing circuit according to Embodiment 2 of the present invention;

4 is a schematic structural diagram of a voltage stabilizing circuit according to Embodiment 2 of the present invention;

FIG. 5 is a schematic structural diagram of a power supply circuit according to an embodiment of the present invention; FIG.

FIG. 6 is a schematic structural diagram of a remote controller according to an embodiment of the present invention.

Reference mark:

100: voltage regulator circuit;

Vcc: input power; Vout: output voltage;

1: controller; 2: feedback circuit; 3: back end hardware module;

Q1: first triode; Q2: second triode;

R1: first current sharing resistor; R2: second current sharing resistor;

C1, C2, C3, C4, C5, C6: Grounding capacitor.

detailed description

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. The following description refers to the same or similar elements in the different figures unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with aspects of the invention as detailed in the appended claims.

The terminology used in the present invention is for the purpose of describing particular embodiments, and is not intended to limit the invention. The singular forms used in the present invention and the appended claims The words "a", "an" and "the" are also intended It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used to describe various information in the present invention, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, the first information may also be referred to as the second information without departing from the scope of the invention. Similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "when" or "in response to a determination."

The voltage stabilizing circuit 100 of the present invention and the power supply circuit and the remote controller having the voltage stabilizing circuit 100 will be described in detail below with reference to the accompanying drawings. The features of the embodiments and embodiments described below may be combined with each other without conflict.

Referring to FIG. 1, a voltage stabilizing circuit 100 according to an embodiment of the present invention includes a controller 1, at least two transistors, and a current sharing resistor corresponding to an emitter connected in series with each transistor. Wherein at least two of the transistors are connected in parallel, and the bases of at least two of the transistors connected in parallel are connected to the control end of the controller 1, the emitter is connected to the input power source Vcc, and at least two are connected in parallel. The collector of the transistor is connected to the back end hardware module 3.

In this embodiment, the controller 1 is configured to acquire signals on the base or collector of at least two of the parallel transistors (hereinafter referred to as a base signal or a collector signal), when the controller 1 When it is determined that the base signal or the collector signal is greater than or less than a preset reference value, outputting a control signal that adjusts the base signal or the collector signal to be equal to the preset reference value to at least two after the parallel connection The base of the triode.

The voltage stabilizing circuit 100 of the present embodiment controls the bases of the at least two transistors and the collectors of the parallel connected signals to the controller 1 to control the bases of the parallelized at least two transistors through the controller 1. So that the base signal or the collector signal is equal in magnitude to the preset reference value, so that the output voltage Vout of the collectors of the at least two of the transistors after the parallel connection is maintained at a desired voltage level (ie, the back end hardware) The power supply voltage required for the operation of the module 3), in turn, provides stable power supply to the back end hardware module 3.

Moreover, the voltage stabilizing circuit 100 of the present embodiment also forms a negative feedback by respectively connecting the current sharing resistors of the emitters of each of the parallel transistors in the parallel triodes, and the negative feedback acts when the current flowing through a triode is excessively large. It will reduce the current flowing through it, and the current flowing through the transistor with smaller current will become larger, and finally the current difference flowing through each transistor will be smaller and more balanced, that is, the voltage regulator circuit can make the flow through The current of each triode is equal (ie, current sharing), and the occurrence of excess circuit of at least two transistors in parallel is reduced, the life of the triode is guaranteed, and the life of the device with the voltage stabilizing circuit is finally guaranteed.

Wherein the base signal or the collector signal is a voltage or current signal, and the predetermined reference value is determined according to an actual required voltage level of the output voltage Vout of the collectors of the at least two transistors after the parallel connection. .

The input power source Vcc is a battery or a circuit module connected to the mains, thereby providing an input voltage to the voltage stabilizing circuit 100, and the voltage input circuit converts the input voltage of the input voltage into a stable output voltage Vout.

In this embodiment, the at least two transistors are two, which are a first transistor Q1 and a second transistor Q2, respectively. The base of the first transistor Q1 is connected to the base of the second transistor Q2, and the collector of the first transistor Q1 is connected to the collector of the second transistor Q2. The emitter of the first transistor Q1 and the emitter of the second transistor Q2 are respectively connected in series with a current sharing resistor, and then connected in parallel, thereby achieving parallel connection of the two transistors.

The first transistor Q1 and the second transistor Q2 may both be PNP type transistors. Therefore, the parameters of the first transistor Q1 and the second transistor Q2 are consistent as much as possible to better achieve current sharing.

Referring to FIG. 1 again, corresponding to the number of the triodes, the current sharing resistors are also two, which are a first current sharing resistor R1 and a second current sharing resistor R2, respectively. The first current sharing resistor R1 is connected to the emitter of the first transistor Q1, and the second current sharing resistor R2 is connected to the emitter of the second transistor Q2.

The first current sharing resistor R1 and the second resistor R2 are connected in series to the emitters of the first transistor Q1 and the second transistor Q2, respectively, thereby forming respective negative feedbacks. Assuming that the current flowing through the first transistor Q1 increases, the voltage drop across the first resistor becomes larger, causing the current flowing through the first transistor Q1 to decrease, and at the same time, flowing through the second transistor. The current of Q2 will increase, and the current flowing through the first transistor Q1 and the second transistor Q2 will be substantially equal.

In order to further ensure that the current flowing through the first transistor Q1 and the second transistor Q2 is the same, the resistances of the first current sharing resistor R1 and the second current sharing resistor R2 are equal.

Table 1 shows the series current sharing resistance of the emitters of the first transistor Q1 and the second transistor Q2 and the current sharing of the emitter series of the first transistor Q1 and the second transistor Q2. In the two cases of resistance, the magnitude of the current flowing through the first transistor Q1 and the second transistor Q2.

Table 1

It can be seen from Table 1 that the current flowing through the first transistor Q1 and the second transistor Q2 is made after the equalizing resistors of the first transistor Q1 and the second transistor Q2 have the same series resistance. They are equal in size, thereby reducing the damage of the first transistor Q1 and the second transistor Q2 because the actual current flowing through the rated current exceeds the rated current.

In this embodiment, the controller 1 can be divided into an LDO controller with an integrated signal detection module and other controllers that are not integrated with a signal detection module. The first embodiment and the second embodiment respectively elaborate on the two types of controllers.

Embodiment 1

Referring to FIG. 2, the controller 1 is an LDO controller, and the LDO controller includes a signal detecting unit (not shown). Wherein the input end of the signal detecting unit is connected to the base or collector of the at least two parallel transistors after the parallel connection, for detecting the base or collector of the at least two of the parallel transistors signal. That is, the LDO controller obtains the signals on the base or collector of the at least two of the parallel transistors through the integrated signal detecting unit thereof, so as to base the at least two of the parallel transistors. The poles are adjusted such that a stable output voltage Vout is outputted on the at least two of the collectors after the parallel connection.

Embodiment 2

The controller 1 is a controller 1 other than an LDO controller, such as an ARM (Advanced RISC Machines, RISC microprocessor), an AVR (RISC) The controller 1 of this type generally does not include a signal detecting unit, such as a high-speed 8-bit single-chip microcomputer or the like, or an ASIC (Application Specific Integrated Circuit) chip. Referring to FIG. 3, in the second embodiment, the voltage stabilizing circuit 100 further includes a feedback circuit 2, and an input end of the feedback circuit 2 is connected to a base or a collector of at least two of the parallel transistors. The output of the feedback circuit 2 is connected to the controller 1. The feedback circuit 2 is configured to detect signals on the base or collector of the at least two of the parallel transistors and send the detected signals to the controller 1.

Optionally, the feedback circuit 2 includes a comparator (not shown), and an input end of the comparator is connected to a base or a collector of at least two of the parallel transistors, the comparator The output of the controller is connected to the controller 1. For example, referring to FIG. 4, the input end of the comparator is connected to the collectors of at least two of the parallel transistors, and the voltages of the collectors of the at least two of the parallel transistors (hereinafter referred to as collectors) The comparator is input to the comparator, and the comparator compares the divided voltage with a preset voltage. If the collector voltage is greater than or less than a reference voltage, the comparator outputs a trigger signal (eg, a high level) Or low level) to the controller 1 to trigger the controller 1 to output a control signal for adjusting the collector voltage equal to the reference voltage to the bases of the at least two transistors after the parallel connection, Thereby, the output voltage Vout of the collectors of the at least two of the parallel transistors is the required voltage level. In this embodiment, the reference voltage is the voltage required for the collectors of the at least two of the transistors after the parallel connection. For example, when the feedback circuit 2 detects that the output voltage Vout of the collectors of the at least two of the parallel transistors is less than the base a quasi-voltage value, then outputting a low level to the controller 1 to trigger the controller 1 to output a control signal that increases the base current of the at least two of the parallel transistors, so that at least the parallel after the parallel The output voltage Vout of the collectors of the two transistors is increased to be equal to the reference voltage, thereby providing a stable supply voltage to the back end hardware module 3.

Optionally, the feedback circuit 2 further includes a voltage dividing circuit (not shown), and the input end of the voltage dividing circuit is connected to the base or collector of the at least two parallel transistors after the parallel connection. After the voltages of the bases or collectors of at least two of the parallel transistors are divided, the divided voltage is input to the comparator, and the comparator divides the divided voltage with a reference voltage, if the partial voltage The voltage is greater than or less than the reference voltage, and the comparator outputs a trigger signal to the controller 1 to trigger the controller 1 to output a control signal that adjusts the divided voltage equal to the preset voltage to the parallel connection. The bases of at least two of the transistors are such that the output voltage Vout of the collectors of the at least two of the parallel transistors is a desired voltage level. In this embodiment, the reference voltage is related to a supply voltage required for the operation of the back end hardware module 3.

Referring to FIG. 1 to FIG. 4, in order to filter the input voltage of the input power source Vcc, the interference of the input end of the voltage stabilizing circuit 100, the input power source Vcc and the parallelized at least two A first filter circuit is also connected between the emitters of the transistors. Optionally, the first filter circuit includes a first capacitor that is grounded. In order to achieve a better filtering effect, the first capacitance of the ground may be a plurality of groups, for example, two groups (C5 to C6 in the figure). Optionally, the first filter circuit is an RC filter circuit.

In this embodiment, the collectors of the at least two of the transistors after the parallel connection are The output voltage Vout is filtered, and a second filter circuit is further connected after the collectors of at least two of the transistors are connected. Optionally, the second filter circuit comprises a second capacitor that is grounded. In order to achieve a better filtering effect, the second capacitor of the ground may be a plurality of groups, for example, four groups (C1 to C4 in the figure). Optionally, the second filter circuit is an RC filter circuit.

In an alternative implementation, the current sharing resistance connected in series with the emitter of each transistor can be moved in series with the collector of each transistor to achieve a current sharing effect of at least two transistors, but a current sharing resistor The current sharing effect that can be achieved by series connection at the collector of each transistor is not as good as connecting the current sharing resistor in series with the emitter of each transistor.

In addition, it should be noted that at least two triodes may be NPN type triodes. In the above implementation manner, the current sharing resistance connected in series to the emitter of each triode needs to be moved to the collector of the corresponding triode, and the current sharing resistor is connected in series. The collectors of the at least two three-stage tubes are connected in parallel and connected to the input power source Vcc, and the emitters of at least two transistors are connected in parallel to output a voltage to the back-end hardware module 3, thereby stably supplying power to the back-end hardware module 3, and other structures and The at least two transistors described above are all similar to the NPN type triode.

The above-described voltage stabilizing circuit 100 can be applied to a power supply circuit that needs to output a stable voltage.

Referring to FIG. 5, a power supply circuit includes an input power source Vcc and the voltage stabilizing circuit 100. The voltage stabilizing circuit 100 is connected to the input power source Vcc and input through the voltage stabilizing circuit 100. The voltage of the power supply Vcc is converted to a stable output voltage Vout, thereby providing a stable voltage source for the back end hardware module 3.

It is worth mentioning that the above power supply circuit can be applied to various devices, for example, a remote controller (such as a WiFi module in a remote controller).

Referring to FIG. 6, a remote controller provided by the present invention includes a back end hardware module 3 and the above power supply circuit, and the power supply circuit is connected to the back end hardware module 3. Specifically, the voltage stabilizing circuit 100 of the power supply circuit is connected to the back end hardware module 3 (such as a WiFi module, etc.) to provide a stable voltage for the back end hardware module 3.

The remote control can be used to control the operation of equipment such as drones, model cars or robots. In this embodiment, the remote controller is a dedicated remote controller for controlling the drone.

The back end hardware module 3 may be a circuit for generating a remote control signal, such as a WiFi module or the like.

The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalents, improvements, etc., which are made within the spirit and principles of the present invention, should be included in the present invention. Within the scope of protection.

Claims

A voltage stabilizing circuit comprising a controller and at least two transistors, further comprising a current sharing resistor corresponding to an emitter connected in series to each of the transistors, wherein at least two of the transistors are connected in parallel, after being connected in parallel The bases of at least two of the transistors are connected to the control terminal of the controller, the emitters are connected to the input power source, and the collectors of the at least two of the parallel transistors are connected to the back end hardware modules.
The voltage stabilizing circuit according to claim 1, wherein the emitters of the at least two of the transistors are connected in series with equal current resistance values.
The voltage stabilizing circuit according to claim 1, wherein said controller is an LDO controller, said LDO controller includes a signal detecting unit, and said signal detecting unit is configured to detect at least two of said parallels A signal on the base or collector of the transistor.
The voltage stabilizing circuit according to claim 1, wherein said voltage stabilizing circuit further comprises a feedback circuit for detecting signals on said base or collector of said at least two of said parallel transistors, and Sending the detected signal to the controller;

An input end of the feedback circuit is connected to a base or a collector of at least two of the parallel transistors, and an output end of the feedback circuit is connected to the controller.
The voltage stabilizing circuit according to claim 4, wherein said feedback circuit comprises a comparator, and an input terminal of said comparator is connected to a base or a collector of said at least two of said parallel transistors The output of the comparator is connected to the controller.
The voltage stabilizing circuit of claim 1 wherein said input power source A grounded first capacitor is further connected between the emitters of the at least two of the transistors connected in parallel.
The voltage stabilizing circuit of claim 1 wherein the collectors of at least two of said transistors are connected to a grounded second capacitor.
The voltage stabilizing circuit according to any one of claims 1 to 7, wherein at least two of said transistors are PNPs.
A power supply circuit comprising an input power supply, characterized by further comprising the voltage stabilizing circuit according to any one of claims 1 to 8, the voltage stabilizing circuit being connected to the input power source.
A remote controller comprising a back end hardware module, characterized by further comprising the power supply circuit of claim 9, the power supply circuit being coupled to the back end hardware module.