CN215934474U - Power supply circuit and power supply - Google Patents
Power supply circuit and power supply Download PDFInfo
- Publication number
- CN215934474U CN215934474U CN202121778540.4U CN202121778540U CN215934474U CN 215934474 U CN215934474 U CN 215934474U CN 202121778540 U CN202121778540 U CN 202121778540U CN 215934474 U CN215934474 U CN 215934474U
- Authority
- CN
- China
- Prior art keywords
- voltage
- power supply
- unit
- circuit
- input end
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Direct Current Feeding And Distribution (AREA)
Abstract
The application relates to a power supply circuit and a power supply. Wherein, this supply circuit includes: the circuit input end is respectively electrically connected with the input end of the detection module, the input end of the low-voltage power supply unit, the input end of the high-voltage power supply unit and the control end of the high-voltage power supply unit; the detection module is used for detecting the voltage of the input end of the circuit, outputting a first level to the control end of the low-voltage power supply unit when detecting that the voltage of the input end of the circuit is greater than a preset load voltage threshold value, and outputting a second level to the control end of the low-voltage power supply unit when detecting that the voltage of the input end of the circuit is less than the preset load voltage threshold value. The problem of among the correlation technique have the power consumption high when low pressure input voltage, reduced the power consumption.
Description
Technical Field
The present application relates to the field of power supply, and in particular, to a power supply circuit and a power supply.
Background
The voltage-stabilizing power supply circuit is a common circuit design and can be realized through a conventional LDO chip, although the conventional LDO chip has high voltage-stabilizing precision, the range of the input voltage which can be borne is generally within 30V, the range is narrow, the voltage-stabilizing power supply circuit cannot be applied under the scene with a large input voltage range, and the LDO chip with a wide input voltage range is used, namely, the high-voltage-resistant LDO chip is expensive, so that the application cost of the voltage-stabilizing power supply circuit can be increased.
In order to solve the technical problem of high cost of the application of the stabilized voltage supply circuit, in the related art, a circuit input end, a circuit output end, a switch unit, a comparison unit and a control unit are arranged in the stabilized voltage supply circuit, and the switch unit is connected between the circuit input end and the circuit output end; the comparison unit is connected with the circuit output end and is grounded, and the comparison unit is used for switching on or switching off the switch unit according to the comparison between the actual output voltage of the circuit output end and the preset output voltage; the control unit is connected with the switch unit, the comparison unit and the circuit input end and is grounded, and the control unit is used for controlling the switch unit to be switched off according to the switching-on of the comparison unit and controlling the switch unit to be switched on according to the switching-off of the comparison unit so as to realize that the stabilized voltage supply circuit is adopted to replace a high-voltage-withstanding LDO chip in a scene with a large input voltage range, and the circuit cost can be effectively reduced. However, in the course of research, it was found that the above-mentioned approach does not reduce the power consumption of the power supply itself at low input voltages.
At present, no effective solution is provided for the problem of high power consumption of a power supply in low-voltage input voltage in the related art.
SUMMERY OF THE UTILITY MODEL
The embodiment of the application provides a power supply circuit and a power supply, and aims to at least solve the problem that power consumption is high when low-voltage input voltage exists in the related art.
In a first aspect, embodiments of the present application provide a power supply circuit,
the power supply device comprises a circuit input end, a detection module, a low-voltage power supply unit and a high-voltage power supply unit, wherein the circuit input end is respectively electrically connected with the input end of the detection module, the input end of the low-voltage power supply unit, the input end of the high-voltage power supply unit and the control end of the high-voltage power supply unit; wherein the content of the first and second substances,
the detection module is used for detecting the voltage of the input end of the circuit, outputting a first level to the control end of the low-voltage power supply unit when detecting that the voltage of the input end of the circuit is greater than a preset load voltage threshold value, and outputting a second level to the control end of the low-voltage power supply unit when detecting that the voltage of the input end of the circuit is less than the preset load voltage threshold value;
when the control end of the low-voltage power supply unit receives the first level, the low-voltage power supply unit is used for disconnecting the circuit input end from the load, the high-voltage power supply unit is used for outputting a second constant voltage to supply power to the load, and when the control end of the low-voltage power supply unit receives the second level, the low-voltage power supply unit is used for connecting the circuit input end with the load and supplying power to the load by using the first constant voltage, and the high-voltage power supply unit is used for disconnecting the circuit input end from the load.
In some of these embodiments, the detection module comprises: a comparison unit, a sampling unit, a voltage stabilizing unit and an N-channel junction field effect transistor, wherein,
the positive input end of the comparison unit is electrically connected with the output end of the sampling unit, the reverse input end of the comparison unit is electrically connected with the voltage stabilizing unit, the output end of the comparison unit is electrically connected with the source electrode of the N-channel junction type field effect transistor, the input end of the sampling unit is electrically connected with the input end of the circuit, the drain electrode of the N-channel junction type field effect transistor is coupled to the control end of the low-voltage power supply unit, the grid electrode of the N-channel junction type field effect transistor is grounded, wherein,
the voltage stabilizing unit is used for providing a first preset voltage for the reverse input end of the comparing unit;
the sampling unit is used for sampling the voltage of the input end of the circuit and inputting the voltage to the positive input end of the comparison unit;
the comparison unit is used for outputting a third level along the output end of the comparison unit when the voltage received by the positive input end is greater than the first preset voltage, and outputting a fourth level along the output end of the comparison unit when the voltage received by the positive input end is not greater than the first preset voltage;
the N-channel junction field effect transistor is used for disconnecting the source electrode of the N-channel junction field effect transistor from the drain electrode of the N-channel junction field effect transistor when the source electrode of the N-channel junction field effect transistor receives the third level and generating the first level, and connecting the source electrode of the N-channel junction field effect transistor with the drain electrode of the N-channel junction field effect transistor when the source electrode of the N-channel junction field effect transistor receives the fourth level and generating the second level.
In some embodiments, the sampling unit includes a first resistor and a second resistor, wherein one end of the first resistor is electrically connected to the circuit input terminal, the other end of the first resistor is electrically connected to the positive input terminal of the comparing unit and one end of the second resistor, respectively, and the other end of the second resistor is grounded.
In some embodiments, the voltage stabilizing unit includes a first diode, a cathode of the first diode is electrically connected to the inverting input terminal of the comparing unit and a third resistor, respectively, an anode of the first diode is grounded, and the other end of the third resistor is grounded, wherein the first diode is configured to maintain the voltage at the inverting input terminal of the comparing unit at the first preset voltage.
In some of these embodiments, the comparison unit comprises a comparator.
In some of these embodiments, the detection module further comprises a fourth resistor coupled between the circuit input and the output of the comparison unit.
In some of these embodiments, the low voltage power supply unit comprises: an NPN type triode and a fifth resistor, wherein the fifth resistor is coupled between the output end of the detection module and the base electrode of the NPN type triode, the input end of the fifth resistor is the control end of the low-voltage power supply unit, the collector electrode of the NPN type triode is coupled to the load, wherein,
the NPN triode is used for disconnecting the collector of the NPN triode from the emitter of the NPN triode when the base receives the first level, and communicating the collector of the NPN triode with the emitter of the NPN triode when the base receives the second level.
In some embodiments, the high voltage power supply unit comprises a PNP type triode, a sixth resistor and a second diode, wherein a collector of the PNP transistor is coupled to the circuit input terminal, a base of the PNP transistor is coupled to a cathode of the second diode, an anode of the second diode is grounded, the sixth resistor is coupled between the circuit input terminal and a base of the PNP transistor, an emitter of the PNP transistor is coupled to the load, wherein the PNP type triode is used for receiving the first level at the control end of the low-voltage power supply unit, communicating the emitter of the PNP type triode with the base of the PNP type triode, and disconnecting the emitter of the PNP type triode and the base of the PNP type triode when the control end of the low-voltage power supply unit receives the second level.
In some embodiments, the high voltage power supply unit further includes a filtering unit, one end of the filtering unit is coupled to an emitter of the PNP type triode, and the other end of the filtering unit is grounded, where the filtering unit is configured to filter an output voltage of the high voltage power supply unit.
In some of these embodiments, the filter unit includes a filter capacitor.
In a second aspect, an embodiment of the present application further provides a power supply, where the power supply includes the power supply circuit of the first aspect.
Compared with the related art, the power supply circuit and the power supply provided by the embodiment of the application have the advantages that the circuit input end, the detection module, the low-voltage power supply unit and the high-voltage power supply unit are arranged in the power supply circuit, the circuit input end is respectively and electrically connected with the input end of the detection module, the input end of the low-voltage power supply unit, the input end of the high-voltage power supply unit and the control end of the high-voltage power supply unit, the output end of the detection module is electrically connected with the control end of the low-voltage power supply unit, and the output end of the low-voltage power supply unit and the output end of the high-voltage power supply unit are both electrically connected with a load; the detection module is used for detecting the voltage of the input end of the circuit, outputting a first level to the control end of the low-voltage power supply unit when detecting that the voltage of the input end of the circuit is greater than a preset load voltage threshold value, and outputting a second level to the control end of the low-voltage power supply unit when detecting that the voltage of the input end of the circuit is less than the preset load voltage threshold value; when the control end of the low-voltage power supply unit receives the first level, the low-voltage power supply unit is used for disconnecting the circuit input end from the load, the high-voltage power supply unit is used for outputting the second constant voltage to supply power to the load, and when the control end of the low-voltage power supply unit receives the second level, the low-voltage power supply unit is used for connecting the circuit input end with the load and supplying power to the load by using the first constant voltage, and the high-voltage power supply unit is used for disconnecting the circuit input end from the load.
The details of one or more embodiments of the application are set forth in the accompanying drawings and the description below to provide a more thorough understanding of the application.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:
FIG. 1 is a block diagram of a power supply circuit according to an embodiment of the present application;
fig. 2 is a schematic structural diagram of a power supply circuit according to an embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments provided in the present application without any inventive step are within the scope of protection of the present application. Moreover, it should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another.
Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of ordinary skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments without conflict.
Unless defined otherwise, technical or scientific terms referred to herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which this application belongs. Reference to "a," "an," "the," and similar words throughout this application are not to be construed as limiting in number, and may refer to the singular or the plural. The present application is directed to the use of the terms "including," "comprising," "having," and any variations thereof, which are intended to cover non-exclusive inclusions; for example, a process, method, system, article, or apparatus that comprises a list of steps or modules (elements) is not limited to the listed steps or elements, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Reference to "connected," "coupled," and the like in this application is not intended to be limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Reference herein to "a plurality" means greater than or equal to two. "and/or" describes an association relationship of associated objects, meaning that three relationships may exist, for example, "A and/or B" may mean: a exists alone, A and B exist simultaneously, and B exists alone. Reference herein to the terms "first," "second," "third," and the like, are merely to distinguish similar objects and do not denote a particular ordering for the objects.
This embodiment provides a power supply circuit, and fig. 1 is a block diagram of a power supply circuit according to an embodiment of the present application, and as shown in fig. 1, the power supply circuit includes: the power supply system comprises a circuit input end, a detection module 10, a low-voltage power supply unit 20 and a high-voltage power supply unit 30, wherein the circuit input end is respectively and electrically connected with the input end of the detection module 10, the input end of the low-voltage power supply unit 20, the input end of the high-voltage power supply unit 30 and a control end of the high-voltage power supply unit 30, the output end of the detection module 10 is electrically connected with the control end of the low-voltage power supply unit 20, and the output end of the low-voltage power supply unit 20 and the output end of the high-voltage power supply unit 30 are electrically connected with a load 40; wherein the content of the first and second substances,
the detection module 10 is configured to detect a voltage at an input end of the circuit, and output a first level to the control end of the low voltage power supply unit 20 when detecting that the voltage at the input end of the circuit is greater than a preset load voltage threshold, and output a second level to the control end of the low voltage power supply unit 20 when detecting that the voltage at the input end of the circuit is less than the preset load voltage threshold.
When the control terminal of the low voltage power supply unit 20 receives the first level, the low voltage power supply unit 20 is configured to disconnect the circuit input terminal from the load 40, and the high voltage power supply unit 30 is configured to output a second constant voltage to supply the load 40.
When the control terminal of the low voltage power supply unit 20 receives the second level, the low voltage power supply unit 20 is configured to connect the circuit input terminal with the load 40 and supply the load 40 with the first constant voltage, and the high voltage power supply unit 30 is configured to disconnect the circuit input terminal from the load 40.
In this embodiment, when the power supply circuit supplies power to operate, the detection module detects a voltage at the input end of the circuit, and when the detection module detects that the voltage at the input end of the circuit is greater than a preset load voltage threshold, the detection module outputs a first level to the control end of the low-voltage power supply unit, and when the control end of the low-voltage power supply unit 20 receives the first level, the low-voltage power supply unit 20 disconnects the input end of the circuit from the load 40, and the high-voltage power supply unit 30 outputs a second constant voltage to supply power to the load 40; when the detection module detects that the voltage at the input end of the circuit is smaller than the preset load voltage threshold value, the detection module outputs a second level to the control end of the low-voltage power supply unit, when the control end of the low-voltage power supply unit 20 receives the second level, the low-voltage power supply unit 20 connects the input end of the circuit with the load 40 and supplies power to the load 40 by using the first constant voltage, and the high-voltage power supply unit 30 disconnects the input end of the circuit from the load 40.
In this embodiment, the low-voltage power supply unit 20 and the high-voltage power supply unit 30 are respectively configured to supply power to the load 40 by setting the detection module 10, outputting a first level to the control terminal of the low-voltage power supply unit 20 when detecting that the voltage at the input end of the circuit is greater than the preset load voltage threshold, and outputting a second level to the control terminal of the low-voltage power supply unit 20 when detecting that the voltage at the input end of the circuit is less than the preset load voltage threshold; under the condition that the detection module 10 outputs the first level, the high-voltage power supply unit 30 outputs the second constant voltage to supply power to the load 40, and under the condition that the detection module 10 outputs the second level, the low-voltage power supply unit 20 is controlled to be switched on, the low-voltage power supply unit 20 connects the circuit input end with the load 40 and supplies power to the load 40 by using the first constant voltage, so that the circuit input end is directly connected with the load 40 to supply power to the load 40, the output voltage drop caused by the effect that the power supply circuit carries the load 40 is avoided, the purpose of reducing the power consumption of the power supply under the working condition of inputting low voltage (namely the voltage of the circuit input end is smaller than the maximum input voltage of the load 40) is realized, and the problem of high power consumption of the power supply in the related technology under the condition of inputting low voltage is solved.
Fig. 2 is a schematic structural diagram of a power supply circuit according to an embodiment of the present application, and as shown in fig. 2, in some embodiments, the detection module 10 includes: the sampling circuit comprises a comparison unit, a sampling unit, a voltage stabilizing unit and an N-channel junction field effect transistor Q3, wherein the positive input end of the comparison unit is electrically connected with the output end of the sampling unit, the negative input end of the comparison unit is electrically connected with the voltage stabilizing unit, the output end of the comparison unit is electrically connected with the source electrode of the N-channel junction field effect transistor Q3, the input end of the sampling unit is electrically connected with the input end of the circuit, the drain electrode of the N-channel junction field effect transistor Q3 is coupled to the control end of the low-voltage power supply unit 20, and the grid electrode of the N-channel junction field effect transistor Q3 is grounded, wherein the voltage stabilizing unit is used for providing a first preset voltage for the negative input end of the comparison unit; the sampling unit is used for sampling the voltage at the input end of the circuit and inputting the voltage to the positive input end of the comparison unit; the comparison unit is used for outputting a third level along the output end of the comparison unit when the voltage received by the positive input end is greater than a first preset voltage, and outputting a fourth level along the output end of the comparison unit when the voltage received by the positive input end is not greater than the first preset voltage; the N-channel jfet Q3 is configured to disconnect its source from its drain and generate a first level when its source receives a third level and to connect its source to its drain and generate a second level when its source receives a fourth level.
It should be noted that the first preset voltage may be less than or equal to the maximum input voltage of the load 40, and may be set according to the actual needs of the user.
In this embodiment, the voltage at the input end of the circuit is divided by the sampling unit, the comparison unit compares the voltage at the forward input end with the voltage stabilizing unit, and inputs the first preset voltage at the reverse input end, and when the voltage at the forward input end is lower than the first preset voltage, the comparison unit outputs a voltage of 0V (i.e. the second level), so as to turn on the N-channel jfet Q3, which realizes that the low voltage power supply unit 20 is controlled to be turned on with the load 40 to couple the circuit input end to the load 40 when detecting that the voltage at the circuit input end is lower than the maximum input voltage of the load 40.
In this embodiment, the voltage at the input end of the circuit is divided by the sampling unit, the voltage at the forward input end is compared with the first preset voltage that is stabilized by the voltage stabilizing unit and input to the reverse input end by the comparing unit, and when the voltage at the forward input end is higher than the first preset voltage, the output voltage at the output end of the comparing unit is the voltage at the input end of the circuit (i.e. the first level), so that in a manner that the N-channel jfet Q3 is turned off, in a case that it is detected that the voltage at the input end of the circuit is greater than the maximum input voltage of the load 40, the low-voltage power supply unit 20 is controlled to be turned off from the load 40, so that the high-voltage power supply unit 30 supplies power to the load 40.
With continued reference to fig. 2, in some embodiments, the sampling unit includes a first resistor R1 and a second resistor R2, wherein one end of the first resistor R1 is electrically connected to the circuit input terminal, the other end of the first resistor R1 is electrically connected to the positive input terminal of the comparing unit and one end of the second resistor R2, respectively, and the other end of the second resistor R2 is grounded.
In this embodiment, the first resistor R1 and the second resistor R2 form a sampling unit, which samples the voltage at the input terminal of the circuit. The voltage of the circuit input end sampled by the sampling unit is input to the positive input end after voltage division, and the comparison unit is equivalent to the voltage of the circuit input end detected by receiving the voltage of the positive input end.
With continued reference to fig. 2, in some embodiments, the voltage regulation unit includes: and a first diode D1A, wherein the cathode of the first diode D1A is electrically connected to the inverting input terminal of the comparing unit and the third resistor R3, respectively, the anode of the first diode D1A is grounded, and the other end of the third resistor R3 is grounded, wherein the first diode D1A is used for maintaining the voltage at the inverting input terminal of the comparing unit at the first preset voltage.
In some alternative embodiments, the voltage of the cathode of the first diode D1A may be the maximum input voltage of the load 40, and in this way, the comparison unit may determine the magnitude of the output voltage according to the maximum input voltage of the load 40, and may determine the power supply mode for the load 40 according to the magnitude of the voltage at the input end of the circuit.
With continued reference to fig. 2, in some of these embodiments, the comparison unit includes: comparator U1A.
In the embodiment, a forward input end of the comparator U1A is coupled to an output end of the sampling unit, a reverse input end of the comparator U1A is coupled to an output end of the voltage stabilizing unit, an output end of the comparator U1A is coupled to a source electrode of the N-channel junction field effect transistor Q3, and comparison between the voltage at the input end of the circuit and a preset load voltage threshold is achieved by arranging the comparator U1A.
With continued reference to fig. 2, in some of these embodiments, the detection module 10 further includes: a fourth resistor R4, a fourth resistor R4 is coupled between the circuit input and the output of the comparison unit.
In this embodiment, the fourth resistor R4 is disposed in the detection module 10 to prevent the voltage at the output end of the circuit from being too high, thereby protecting the detection module 10.
With continued reference to fig. 2, in some of these embodiments, the low voltage power supply unit 20 includes: an NPN transistor and a fifth resistor R5, the fifth resistor R5 is coupled between the output terminal of the detection module 10 and the base of the NPN transistor Q2, the input terminal of the fifth resistor R5 is the control terminal of the low voltage power supply unit 20, and the collector of the NPN transistor Q2 is electrically connected to the load 40, wherein the NPN transistor Q2 is configured to disconnect the collector of the NPN transistor Q2 from the emitter of the NPN transistor Q2 when the base receives the first level, and connect the collector of the NPN transistor Q2 to the emitter of the NPN transistor Q2 when the base receives the second level.
In the present embodiment, by providing the NPN transistor and the fifth resistor R5 in the low voltage power supply unit 20, the collector of the NPN transistor Q2 and the emitter of the NPN transistor Q2 are kept disconnected when the detection module 10 outputs the first level, so that the high voltage power supply to the load 40 is realized, and the collector of the NPN transistor Q2 and the emitter of the NPN transistor Q2 are kept connected when the detection module 10 outputs the second level, so that the low voltage power supply to the load 40 is realized.
In this embodiment, a fifth resistor R5 is disposed at the base of the NPN transistor Q2, and the fifth resistor R5 is a current-limiting resistor at the base of the NPN transistor Q2, so as to prevent the detection module 10 from generating an excessive output current and damaging the NPN transistor Q2.
It should be noted that, by arranging the NPN type triode and the fifth resistor R5 in the low voltage power supply unit 20, and enabling the connection with the load 40 to be conducted under the condition that the detection module outputs the second level, because the NPN type triode is conducted at this time, its internal resistance is very small (generally several m Ω) and can be almost ignored, the voltage at the input end of the circuit can be equal to the output voltage of the low voltage power supply unit 20, thereby reducing the power consumption of the power supply itself, and simultaneously avoiding the problem of output voltage drop caused by the load effect of the power supply circuit, and achieving the purpose of reducing the power consumption of the power supply under the working condition of inputting low voltage (i.e. the voltage at the input end of the circuit is less than the maximum input voltage of the load 40).
With continued reference to fig. 2, in some of these embodiments, the high voltage power supply unit 30 includes: a PNP transistor Q1, a sixth resistor R6, and a second diode D2A, wherein a collector of the PNP transistor Q1 is electrically connected to the circuit input, a base of the PNP transistor Q1 is electrically connected to the cathode of the second diode D2A, an anode of the second diode D2A is grounded, the sixth resistor R6 is coupled between the circuit input and the base of the PNP transistor Q1, and an emitter of the PNP transistor Q1 is electrically connected to the load 40, wherein the PNP transistor Q1 is configured to connect the emitter of the PNP transistor Q1 to the base of the PNP transistor Q1 when the control terminal of the low voltage power supply unit 20 receives the first level, and disconnect the emitter of the PNP transistor Q1 from the base of the PNP transistor Q1 when the control terminal of the low voltage power supply unit 20 receives the second level.
In the present embodiment, by providing the PNP transistor Q1, the sixth resistor R6, and the second diode D2A in the high voltage power supply unit 30, the PNP transistor Q1 is kept connected when the detection module 10 outputs the first level, so that the high voltage power supply to the load 40 is realized, and the PNP transistor Q1 is kept disconnected when the detection module 10 outputs the second level, so that the low voltage power supply unit 20 is realized to supply the low voltage power to the load 40.
It should be noted that, in the case that the PNP transistor Q1 is kept in the conducting state, the output voltage of the high voltage power supply unit 30 is the voltage of the second diode D2A minus the emitter junction voltage (i.e. the voltage between the base and the emitter) of the PNP transistor Q1, and in this embodiment, the voltage regulation of the high voltage power supply unit 30 can be realized through the second diode D2A, and the output voltage of the PNP transistor can also be made not greater than the maximum input voltage of the load, so as to realize the protection of the load.
In this embodiment, the sixth resistor R6 is provided to realize the current limiting function, so as to avoid the problem that the input terminal of the high voltage power supply unit 30 is too high in voltage and the high voltage power supply unit 30 is damaged.
With continued reference to fig. 2, in some embodiments, the high voltage power supply unit further includes a filtering unit, one end of the filtering unit is electrically connected to an emitter of the PNP type triode, and the other end of the filtering unit is grounded, wherein the filtering unit is configured to filter an output voltage of the high voltage power supply unit.
In this embodiment, the filtering unit includes a filtering capacitor C2, wherein one end of the filtering capacitor C2 is coupled to the emitter of the PNP transistor Q1, and the other end of the filtering capacitor C2 is grounded, so that the filtering of the high voltage power supply unit 30 is implemented by providing the filtering capacitor C2 in the high voltage power supply unit. It should be noted that, in some optional embodiments, the filtering unit that is required to filter the output voltage of the high-voltage power supply unit is suitable for the filtering unit of this embodiment, for example: pi-type filter circuit and filter.
The following description and illustrations represent a preferred embodiment.
With continued reference to fig. 2, the power supply circuit is described and illustrated as being applied to a camera, wherein a load 40 within the camera is capable of withstanding a maximum input voltage Vload-maxThe input voltage of the input end of the whole equipment is VinAnd the working conditions are defined as follows:
Vin>Vload-max: a second input voltage.
Vin<Vload-max: a first input voltage.
In the present embodiment, the detecting module 10 detects the input voltage V at the input end of the circuit under the condition of the second input voltage (i.e. the voltage at the input end of the circuit is greater than the maximum input voltage of the load 40)inAfter the resistors R1 and R2 divide the voltage, the positive input voltage of the comparator U1A is higher than the voltage of the negative first diode D1A, and the comparator U1A outputs the saturated high voltage Vin(i.e., the first level in the above embodiment), at this time, the N-channel jfet Q3 is pinched off, and further, the NPN transistor Q2 does not satisfy the on condition, and is in the off state, the high voltage power supply unit 30 starts to supply power, and the output voltage is the voltage of the second diode D2A minus the emitter junction voltage of the PNP transistor Q1.
In the present embodiment, the detection module 10 detects the input voltage V at the input end of the circuit under the condition of the first input voltage (i.e. the voltage at the input end of the circuit is less than the maximum input voltage of the load 40)inAfter the resistors R1 and R2 are divided, the positive input voltage of the comparator U1A is lower than the voltage of the negative first diode D1A, the output of the comparator U1A is 0V (i.e., the second level in the above embodiment), the N-channel jfet Q3 is conductive, the Q3 is fully opened, the Q2 is fully opened, the collector and emitter of the PNP triode Q1 of the high-voltage power supply unit 30 are clamped at 0V, the high-voltage power supply unit 30 does not work, the Q2 is fully opened, the input power supply at the input end of the circuit is directly connected to the load (e.g., RL in fig. 2) 40, and the on-resistance of the Q2 is several m Ω.
By the mode, the power consumption of the power supply circuit is reduced, the output voltage drop caused by the effect that the power supply circuit carries the load 40 is avoided, and the beneficial effect that the power supply is input under the low-voltage working condition and the power consumption is reduced is achieved.
The embodiment of the application also provides a power supply, and the power supply comprises the power supply circuit in the embodiment. By the mode, the power supply has the beneficial effect of reducing power consumption under the working condition of low input voltage (namely the voltage at the input end of the circuit is less than the maximum input voltage of the load 40).
It should be understood by those skilled in the art that various features of the above-described embodiments can be combined in any combination, and for the sake of brevity, all possible combinations of features in the above-described embodiments are not described in detail, but rather, all combinations of features which are not inconsistent with each other should be construed as being within the scope of the present disclosure.
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the embodiments of the present application. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (11)
1. A power supply circuit is characterized by comprising a circuit input end, a detection module, a low-voltage power supply unit and a high-voltage power supply unit, wherein the circuit input end is respectively and electrically connected with the input end of the detection module, the input end of the low-voltage power supply unit, the input end of the high-voltage power supply unit and the control end of the high-voltage power supply unit; wherein the content of the first and second substances,
the detection module is used for detecting the voltage of the input end of the circuit, outputting a first level to the control end of the low-voltage power supply unit when detecting that the voltage of the input end of the circuit is greater than a preset load voltage threshold value, and outputting a second level to the control end of the low-voltage power supply unit when detecting that the voltage of the input end of the circuit is less than the preset load voltage threshold value;
when the control end of the low-voltage power supply unit receives the first level, the low-voltage power supply unit is used for disconnecting the circuit input end from the load, the high-voltage power supply unit is used for outputting a second constant voltage to supply power to the load, and when the control end of the low-voltage power supply unit receives the second level, the low-voltage power supply unit is used for connecting the circuit input end with the load and supplying power to the load by using the first constant voltage, and the high-voltage power supply unit is used for disconnecting the circuit input end from the load.
2. The power supply circuit of claim 1, wherein the detection module comprises: a comparison unit, a sampling unit, a voltage stabilizing unit and an N-channel junction field effect transistor, wherein,
the positive input end of the comparison unit is electrically connected with the output end of the sampling unit, the reverse input end of the comparison unit is electrically connected with the voltage stabilizing unit, the output end of the comparison unit is electrically connected with the source electrode of the N-channel junction type field effect transistor, the input end of the sampling unit is electrically connected with the input end of the circuit, the drain electrode of the N-channel junction type field effect transistor is coupled to the control end of the low-voltage power supply unit, the grid electrode of the N-channel junction type field effect transistor is grounded, wherein,
the voltage stabilizing unit is used for providing a first preset voltage for the reverse input end of the comparing unit;
the sampling unit is used for sampling the voltage of the input end of the circuit and inputting the voltage to the positive input end of the comparison unit;
the comparison unit is used for outputting a third level along the output end of the comparison unit when the voltage received by the positive input end is greater than the first preset voltage, and outputting a fourth level along the output end of the comparison unit when the voltage received by the positive input end is not greater than the first preset voltage;
the N-channel junction field effect transistor is used for disconnecting the source electrode of the N-channel junction field effect transistor from the drain electrode of the N-channel junction field effect transistor when the source electrode of the N-channel junction field effect transistor receives the third level and generating the first level, and connecting the source electrode of the N-channel junction field effect transistor with the drain electrode of the N-channel junction field effect transistor when the source electrode of the N-channel junction field effect transistor receives the fourth level and generating the second level.
3. The power supply circuit according to claim 2, wherein the sampling unit comprises a first resistor and a second resistor, wherein one end of the first resistor is electrically connected to the circuit input terminal, the other end of the first resistor is electrically connected to the positive input terminal of the comparing unit and one end of the second resistor, respectively, and the other end of the second resistor is grounded.
4. The power supply circuit of claim 2, wherein the voltage stabilizing unit comprises a first diode, a cathode of the first diode is electrically connected to the inverting input terminal of the comparing unit and a third resistor, respectively, an anode of the first diode is grounded, and the other end of the third resistor is grounded, wherein the first diode is configured to maintain the voltage at the inverting input terminal of the comparing unit at the first preset voltage.
5. The power supply circuit according to claim 2, wherein the comparison unit includes a comparator.
6. The power supply circuit of claim 2, wherein the detection module further comprises a fourth resistor coupled between the circuit input and the output of the comparison unit.
7. The power supply circuit according to claim 1, wherein the low voltage power supply unit comprises: an NPN type triode and a fifth resistor, wherein the fifth resistor is coupled between the output end of the detection module and the base electrode of the NPN type triode, the input end of the fifth resistor is the control end of the low-voltage power supply unit, the collector electrode of the NPN type triode is coupled to the load, wherein,
the NPN type triode is used for disconnecting the collector electrode of the NPN type triode from the emitting electrode of the NPN type triode when the base electrode receives the first level, and communicating the collector electrode of the NPN type triode with the emitting electrode of the NPN type triode when the base electrode receives the second level.
8. The power supply circuit of claim 1, wherein the high voltage power supply unit comprises a PNP type triode, a sixth resistor and a second diode, wherein a collector of the PNP transistor is coupled to the circuit input terminal, a base of the PNP transistor is coupled to a cathode of the second diode, an anode of the second diode is grounded, the sixth resistor is coupled between the circuit input terminal and a base of the PNP transistor, an emitter of the PNP transistor is coupled to the load, wherein the PNP type triode is used for receiving the first level at the control end of the low-voltage power supply unit, communicating the emitter of the PNP type triode with the base of the PNP type triode, and disconnecting the emitter of the PNP type triode and the base of the PNP type triode when the control end of the low-voltage power supply unit receives the second level.
9. The power supply circuit according to claim 8, wherein the high voltage power supply unit further comprises a filtering unit, one end of the filtering unit is coupled to an emitter of the PNP type triode, and the other end of the filtering unit is grounded, wherein the filtering unit is configured to filter an output voltage of the high voltage power supply unit.
10. The power supply circuit of claim 9, wherein the filter unit comprises a filter capacitor.
11. A power supply, characterized in that it comprises a power supply circuit according to any one of claims 1 to 10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121778540.4U CN215934474U (en) | 2021-07-30 | 2021-07-30 | Power supply circuit and power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121778540.4U CN215934474U (en) | 2021-07-30 | 2021-07-30 | Power supply circuit and power supply |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN215934474U true CN215934474U (en) | 2022-03-01 |
Family
ID=80399332
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202121778540.4U Active CN215934474U (en) | 2021-07-30 | 2021-07-30 | Power supply circuit and power supply |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN215934474U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114911297A (en) * | 2022-05-23 | 2022-08-16 | 峰岹科技(深圳)股份有限公司 | Drive control circuit for LDO circuit, LDO circuit and chip thereof |
-
2021
- 2021-07-30 CN CN202121778540.4U patent/CN215934474U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114911297A (en) * | 2022-05-23 | 2022-08-16 | 峰岹科技(深圳)股份有限公司 | Drive control circuit for LDO circuit, LDO circuit and chip thereof |
| CN114911297B (en) * | 2022-05-23 | 2023-08-08 | 峰岹科技(深圳)股份有限公司 | Drive control circuit for LDO circuit, LDO circuit and chip thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201523320U (en) | Slow start device of direct current power supply | |
| US9293925B2 (en) | Charging and power supplying circuit, method and application device | |
| US9667055B2 (en) | Over-voltage protection apparatus and method of operating the same | |
| KR20200075849A (en) | Charging device and terminal | |
| CN108539830B (en) | Charging switching control circuit and control method | |
| CN214755708U (en) | Dual-input power supply control circuit with constant voltage switching | |
| CN208904889U (en) | Power supply timing control circuit | |
| CN215934474U (en) | Power supply circuit and power supply | |
| CN108471228A (en) | A kind of quick leadage circuit of DC/DC conversion modules output voltage and its implementation | |
| CN114024355A (en) | Battery management circuit, battery management system, electric vehicle and battery management method | |
| CN103376748A (en) | Electronic device | |
| CN218920268U (en) | Voltage selection circuit, power supply circuit and electronic equipment | |
| CN115296285A (en) | Power protection circuit, method, device and computer storage medium | |
| CN111009958B (en) | Power supply control circuit | |
| CN113541458B (en) | Filter circuit | |
| CN117251012A (en) | Voltage switching circuit and power supply system using the same | |
| CN210578266U (en) | Synchronous rectification control circuit and isolated power supply conversion circuit | |
| CN207926260U (en) | A kind of multiple-way supply automatic switch-over circuit and supply unit | |
| CN220342327U (en) | PSE equipment with automatic identification function | |
| CN110518543A (en) | A kind of short-circuit protection circuit and power supply system | |
| CN1288842C (en) | High-frequency signal switching | |
| CN218867909U (en) | Short-circuit protection circuit, port power supply and electronic equipment | |
| CN214125141U (en) | Current transformer protection circuit and arc discharge detection circuit | |
| CN215187494U (en) | Constant current control circuit and LED circuit | |
| CN220896320U (en) | Driving protection circuit of switching device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |