阅读说明：本技术 一种多负载运行下的电压校准电路及电源供电系统 (Voltage calibration circuit and power supply system under multi-load operation ) 是由 冯子秋 于 2021-07-16 设计创作，主要内容包括：本发明公开了一种多负载运行下的电压校准电路及电源供电系统,该电压校准电路包括：与每个负载端一一对应连接的各条感测线和具有多个输入端的调节模块,其中,调节模块的每个输入端分别与对应负载的感测线连接,调节模块的输出端与电源模块的反馈端连接；调节模块,用于获取各个负载的电压值,并依据每个负载的电压值得到电压平均值,将电压平均值通过电源模块的分压模组反馈至反馈端,使反馈端的电压为基于各个负载的平均电压值得到的,以免因某个负载上电流发生变化时,负载损坏及电源模块的输出电压超出IC需求范围,使系统正常工作。(The invention discloses a voltage calibration circuit and a power supply system under multi-load operation, wherein the voltage calibration circuit comprises: each sensing line is connected with each load end in a one-to-one correspondence mode, and the adjusting module is provided with a plurality of input ends, wherein each input end of the adjusting module is connected with the sensing line of the corresponding load, and the output end of the adjusting module is connected with the feedback end of the power supply module; and the adjusting module is used for acquiring the voltage value of each load, obtaining a voltage average value according to the voltage value of each load, and feeding the voltage average value back to the feedback end through the voltage dividing module of the power supply module, so that the voltage of the feedback end is obtained based on the average voltage value of each load, and the situation that when the current on a certain load changes, the load is damaged, the output voltage of the power supply module exceeds the IC (integrated circuit) requirement range is avoided, and the system works normally.)

1. A voltage calibration circuit under multi-load operation, comprising: each sensing line is connected with each load end in a one-to-one correspondence mode, and the adjusting module is provided with a plurality of input ends, wherein each input end of the adjusting module is connected with the sensing line of the corresponding load, and the output end of the adjusting module is connected with the feedback end of the power supply module; the adjusting module is used for obtaining the voltage value of each load, obtaining a voltage average value according to the voltage value of each load, and feeding the voltage average value back to the feedback end through the voltage dividing module of the power supply module.

2. The voltage calibration circuit under multi-load operation according to claim 1, wherein the adjusting module comprises an operational amplifier, a first resistor, a second resistor, and n third resistors, wherein n is the total number of loads;

the first end of each third resistor is connected with a corresponding sensing line, the second end of each third resistor is connected with the positive input end of the operational amplifier, the first end of the first resistor is connected with the first end of the second resistor, the common end of the first resistor is connected with the negative input end of the operational amplifier, the second end of the second resistor is grounded, the second end of the first resistor is connected with the output end of the operational amplifier, and the common end of the first resistor is used as the output end of the adjusting module.

3. The voltage calibration circuit under multi-load operation according to claim 1, further comprising a start module, wherein an input terminal of the start module is connected to an output terminal of the power module, and an output terminal of the start module is connected to a feedback terminal of the power module; wherein:

the starting module is used for conducting when the power supply module is started and disconnecting when the voltage of the feedback end reaches a preset value.

4. The voltage calibration circuit under multi-load operation according to claim 3, wherein the start module comprises a fourth resistor and a controllable switch, a first end of the fourth resistor is connected to the pin terminal of the power module, a second end of the fourth resistor is connected to ground and is also connected to the control terminal of the controllable switch, an output terminal of the power module is connected to the first end of the controllable switch, a second end of the controllable switch is connected to the feedback terminal as the output terminal of the start module, the controllable switch is turned on when the power module is started, and the controllable switch is turned off when the voltage at the second end of the controllable switch rises to a preset value.

5. The voltage calibration circuit under multi-load operation according to claim 4, wherein the controllable switch is an NMOS, a gate of the NMOS is used as the control terminal of the controllable switch, a drain of the NMOS is used as the first terminal of the controllable switch, and a source of the NMOS is used as the second terminal of the controllable switch.

6. The voltage calibration circuit under multi-load operation according to claim 4, wherein the start-up module further comprises a fifth resistor, a first terminal of the fifth resistor is connected to a second terminal of the fourth resistor, a common terminal of the fifth resistor is connected to the control terminal of the controllable switch, and a second terminal of the fifth resistor is connected to ground.

7. The voltage calibration circuit under multi-load operation according to claim 1, wherein the third resistor has a resistance of not less than 200K Ω.

8. A power supply system comprising a power supply module and a voltage calibration circuit according to any one of claims 1 to 7 under multi-load operation; the power module comprises a power module and a voltage division module, the voltage division module comprises a first voltage division resistor and a second voltage division resistor, the first end of the first voltage division resistor is connected with the first end of the second voltage division resistor, the common end of the first voltage division resistor is connected with the feedback end of the power module, the second end of the first voltage division resistor is used as the feedback end of the power module and is connected with the output end of an adjusting module in the voltage calibration circuit under the multi-load operation, and the second end of the second voltage division resistor is grounded.

Technical Field

The invention relates to the technical field of power supply systems, in particular to a voltage calibration circuit under multi-load operation and a power supply system.

Background

The development of the integrated technology enriches the functions which can be realized by the IC, simultaneously, the required voltage levels tend to be synchronous, and some devices integrate a voltage conversion device in the devices, so that the voltage conversion device not only can provide energy support for the operation of internal logic, but also can be output to the outside and supplied to other equipment for use. At present, multiple types of ICs in the whole system can use one power supply, the existing design scheme generally converts 220V commercial power into a main scheme of 54V or 12V through technologies such as rectification and voltage reduction, and then the system obtains 5V, 3.3V and other multi-path loads from 12V through a BUCK (voltage reduction circuit) for power supply, and the architecture thereof is as shown in fig. 1.

In the existing IC technology, a controller used in the BUCK circuit is integrated with an MOS, and voltage regulation is performed through an external hardware design, wherein a FB (Feed Back) pin of the IC in fig. 1 is generally used as a voltage monitoring pin, when a specific design is used, a sense line is led out from a load end, an obtained signal is fed Back to the FB pin of the IC through a voltage dividing resistor, and output voltage can be regulated by reasonably adjusting the value of the voltage dividing resistor.

If only one load is arranged at the rear end of the power supply, a sense point can be placed close to the load side, so that the voltage loss caused by the path impedance of the PCB when the load current is too large can be avoided, and the voltage of the load point is maintained at the level required by the IC.

However, as shown in fig. 2, when a plurality of loads in a system use the same power supply, and one of the loads may be used as both the power supply and the load, a sense line is led out from one load in the prior art, and a sense line is usually led out from the nearest or farthest load, when the current of the other load changes, such an arrangement may cause the voltage on the other load on the power supply path to be too high or too low, which may damage the load, and may also cause a part of the port output voltage to exceed the required range of the IC, thereby causing the system to operate abnormally.

Therefore, how to provide a voltage calibration circuit and a power supply system under multi-load operation to solve the above technical problems becomes a problem to be solved by those skilled in the art.

Disclosure of Invention

The embodiment of the invention aims to provide a voltage calibration circuit and a power supply system under multi-load operation, which can avoid load damage and output voltage of a power supply module exceeding the IC requirement range when current on a certain load changes to a certain extent in the use process, so that the system can work normally.

To solve the above technical problem, an embodiment of the present invention provides a voltage calibration circuit under multi-load operation, including: each sensing line is connected with each load end in a one-to-one correspondence mode, and the adjusting module is provided with a plurality of input ends, wherein each input end of the adjusting module is connected with the sensing line of the corresponding load, and the output end of the adjusting module is connected with the feedback end of the power supply module; the adjusting module is used for obtaining the voltage value of each load, obtaining a voltage average value according to the voltage value of each load, and feeding the voltage average value back to the feedback end through the voltage dividing module of the power supply module.

Optionally, the adjusting module includes an operational amplifier, a first resistor, a second resistor, and n third resistors, where n is the total number of loads;

the first end of each third resistor is connected with a corresponding sensing line, the second end of each third resistor is connected with the positive input end of the operational amplifier, the first end of the first resistor is connected with the first end of the second resistor, the common end of the first resistor is connected with the negative input end of the operational amplifier, the second end of the second resistor is grounded, the second end of the first resistor is connected with the output end of the operational amplifier, and the common end of the first resistor is used as the output end of the adjusting module.

Optionally, the power supply further comprises a starting module, an input end of the starting module is connected with an output end of the power supply module, and an output end of the starting module is connected with a feedback end of the power supply module; wherein:

the starting module is used for conducting when the power supply module is started and disconnecting when the voltage of the feedback end reaches a preset value.

Optionally, the starting module includes a fourth resistor and a controllable switch, a first end of the fourth resistor is connected to the pin end of the power module, a second end of the fourth resistor is grounded and connected to the control end of the controllable switch, an output end of the power module is connected to the first end of the controllable switch, a second end of the controllable switch is used as the output end of the starting module and connected to the feedback end, when the power module is started, the controllable switch is turned on, and when a voltage of the second end of the controllable switch is increased to a preset value, the controllable switch is turned off.

Optionally, the controllable switch is an NMOS, a gate of the NMOS serves as a control end of the controllable switch, a drain of the NMOS serves as a first end of the controllable switch, and a source of the NMOS serves as a second end of the controllable switch.

Optionally, the starting module further includes a fifth resistor, a first end of the fifth resistor is connected to the second end of the fourth resistor, a common end of the fifth resistor is connected to the control end of the controllable switch, and a second end of the fifth resistor is grounded.

Optionally, the resistance of the third resistor is not lower than 200K Ω.

The embodiment of the invention also provides a power supply system, which comprises a power module and the voltage calibration circuit under the multi-load operation; the power module comprises a power module and a voltage division module, the voltage division module comprises a first voltage division resistor and a second voltage division resistor, the first end of the first voltage division resistor is connected with the first end of the second voltage division resistor, the common end of the first voltage division resistor is connected with the feedback end of the power module, the second end of the first voltage division resistor is used as the feedback end of the power module and is connected with the output end of an adjusting module in the voltage calibration circuit under the multi-load operation, and the second end of the second voltage division resistor is grounded.

The embodiment of the invention provides a voltage calibration circuit and a power supply system under multi-load operation, wherein the voltage calibration circuit comprises: each sensing line is connected with each load end in a one-to-one correspondence mode, and the adjusting module is provided with a plurality of input ends, wherein each input end of the adjusting module is connected with the sensing line of the corresponding load, and the output end of the adjusting module is connected with the feedback end of the power supply module; and the adjusting module is used for acquiring the voltage value of each load, obtaining a voltage average value according to the voltage value of each load, and feeding the voltage average value back to the feedback end through the voltage division module of the power supply module.

Therefore, in the embodiment of the invention, one sensing line is respectively led out from each load, each input end of the adjusting module is respectively connected with one sensing line, the output end of the adjusting module is connected with the feedback end of the power module, the adjusting module can obtain the average voltage value of each load and transmit the average voltage value to the power module through the feedback end, and the average voltage value is fed back to the feedback end through the voltage division module in the power module, so that the voltage of the feedback end is obtained based on the average voltage value of each load, and the load damage and the output voltage of the power module exceeding the IC requirement range when the current on a certain load changes are avoided, and the system can normally work.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed in the prior art and the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic diagram of a conventional voltage step-down circuit;

FIG. 2 is a schematic diagram of a multi-load buck circuit;

fig. 3 is a schematic structural diagram of a voltage calibration circuit under multi-load operation according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of another voltage calibration circuit under multi-load operation according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of another voltage calibration circuit under multi-load operation according to an embodiment of the present invention.

Detailed Description

The embodiment of the invention provides a voltage calibration circuit and a power supply system under multi-load operation, which can avoid the damage of a load and the output voltage of a power supply module exceeding the IC requirement range when the current on a certain load changes to a certain extent in the use process, so that the system can work normally.

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 3, fig. 3 is a schematic structural diagram of a voltage calibration circuit under multi-load operation according to an embodiment of the present invention. The voltage calibration circuit under multi-load operation includes: each sensing sense line 1 connected with each load end in a one-to-one correspondence manner and an adjusting module 2 with a plurality of input ends, wherein each input end of the adjusting module 2 is respectively connected with the sense line 1 of the corresponding load, and the output end of the adjusting module 2 is connected with the feedback end of a power module 3; and the adjusting module 2 is used for acquiring the voltage value of each load, obtaining a voltage average value according to the voltage value of each load, and feeding the voltage average value back to the FB end through the voltage division module of the power module 3.

It should be noted that, in the embodiment of the present invention, for a plurality of loads, a sense line 1 is led out from each load, and a regulation module 2 is provided, where the regulation module 2 is provided with a plurality of input ends, each input end is connected to one sense line 1, the regulation module 2 is connected to a corresponding load through each sense line 1, the regulation module 2 can obtain a voltage average value of a plurality of load voltage values according to a voltage value of each load, and feed back the voltage average value to a feedback end of the power module 3 through an output end a point, and a feedback end of the power module 3 is fed back to an FB end of the power module 3 through a voltage dividing module inside the power module 3, so that a voltage obtained at the FB end is obtained according to the average value of each load, and output of the power module 3 does not exceed an IC demand range due to current change on a certain load, thereby enabling a system to operate normally, the voltage dividing module may specifically include two voltage dividing resistors R1 and R2.

Further, referring to fig. 4 to 5, the adjusting module 2 includes an operational amplifier 21, a first resistor 22, a second resistor 23, and n third resistors 24, where n is the total number of loads;

the first end of each third resistor 24 is connected to the corresponding sense line 1, the second end of each third resistor 24 is connected to the positive input terminal of the operational amplifier 21, the first end of the first resistor 22 is connected to the first end of the second resistor 23, the common end of the first resistor 22 is connected to the negative input terminal of the operational amplifier 21, the second end of the second resistor 23 is grounded, the second end of the first resistor 22 is connected to the output terminal of the operational amplifier 21, and the common end of the first resistor 22 is used as the output terminal of the adjusting module 2.

It should be noted that, the adjusting module 2 in the embodiment of the present invention is mainly composed of an operational amplifier 21, the voltage value at the point B is equal to the average value of the sum of the voltages of the loads, that is, the sum of the voltages of the loads is divided by n to obtain the average value of the voltages, in practical applications, the resistance of the first resistor 22 may be set to be 0, the resistance of the second resistor 23 may be set to be 10K Ω, and in order to avoid the mutual leakage between different loads, the resistance value of the third resistor 24 may not be lower than 200K Ω, at this time, the voltage at the point a of the output end of the regulating module 2 is the average voltage value of each load, therefore, voltage correction under the condition of multiple loads is realized, so that the output of the power supply module 3 does not exceed the IC requirement range. Specifically, the power module 3 includes two voltage dividing resistors R1 and R2, respectively, and the reference voltage at the FB terminal of the power module 3 is Vfb, and the output voltage can reach a preset voltage value by configuring specific resistance values of R1 and R2, where Vout is (R1+ R2)/R2 Vfb.

For example, if there are three loads in the system, that is, n is 3, the sense voltages at the three load ends are connected to the operational amplifier 21 through the corresponding third resistors 23, in order to avoid the mutual leakage between different loads, the resistance of the third resistor 24 may be not lower than 200K Ω, and according to the principle of node current, the sum of the currents flowing into the point B is 0, and the following calculation relationship may be obtained:

further the method can be used for obtaining the compound,that is, the voltage of the series connection point B is the average value of the three load voltages, and at this time, the resistance value of the first resistor 22 is configured to be 0, the resistance value of the second resistor 23 is configured to be 10K Ω, and the voltage average value of each load voltage at the point a is set.

Furthermore, in order to quickly raise the output voltage to a specified value in the starting process of the power supply module, the embodiment of the invention may further include a starting module 4, an input end of the starting module 4 is connected with an output end of the power supply module 3, and an output end of the starting module 4 is connected with a feedback end of the power supply module 3; wherein:

and the starting module 4 is used for conducting when the power supply module 3 is started and disconnecting when the voltage of the feedback end reaches a preset value.

Specifically, since there is a certain delay in leading the voltage at the far-end load to the feedback end of the power module 3 when the power module 3 is started, in the embodiment of the present invention, the start module 4 is turned on when the power module 3 is started, so as to quickly lead the near-end voltage to the feedback end of the power module 3, where the start module 4 specifically leads the voltage led from the power module 3 to the feedback end of the power module 3, so as to quickly raise the output voltage to a specified value.

Furthermore, the starting module 4 in the embodiment of the present invention includes a fourth resistor 41 and a controllable switch 42, a first end of the fourth resistor 41 is connected to the pin end of the power module 3, a second end of the fourth resistor 41 is grounded and is connected to the control end of the controllable switch 42, an output end of the power module 3 is connected to the first end of the controllable switch 42, and a second end of the controllable switch 42 is connected to the feedback end as the output end of the starting module 4, when the power module 3 is started, the controllable switch 42 is turned on, and when the voltage at the second end of the controllable switch 42 rises to a preset value, the controllable switch 42 is turned off.

Specifically, in the embodiment of the present invention, a voltage VCC may be led out from the pin end of one pin of the power module 3, and is connected to the control end of the controllable switch 42 through the fourth resistor 41 of the voltage dividing resistor, when the power module 4 is started, the controllable switch 42 is controlled to be turned on through the voltage VCC, and after the controllable switch 42 is turned on, the voltage at the second end (i.e., a point a) of the controllable switch 42 may be increased, and when the voltage is increased to a preset value, the controllable switch 42 is turned off, and at this time, the voltage at the point a is the output voltage of the adjusting module 2, that is, the average value of the voltages of the respective loads.

Furthermore, the controllable switch 42 in the embodiment of the present invention may be an NMOS, a gate of the NMOS serves as a control terminal of the controllable switch, a drain of the NMOS serves as a first terminal of the controllable switch, and a source of the NMOS serves as a second terminal of the controllable switch. Specifically, the starting module 4 in the embodiment of the present invention may further include a fifth resistor 43, a first end of the fifth resistor 43 is connected to the second end of the fourth resistor 41, a common end of the fifth resistor 43 is connected to the control end of the controllable switch 42, and a second end of the fifth resistor 43 is grounded.

It should be noted that the Q1gate point of the NMOS can be turned off when Vout reaches the normal voltage value by arranging to the fourth resistor 41 and the fifth resistor 43, that is, Vg-Vout < vgs (th).

For example, a power supply with model number MPQ8633A and an output voltage of 3.3V are taken as an example for explanation, where n is 3 specifically as follows:

the FB reference voltage of MPQ8633A is 0.6V, according to the calculation formula Vout ═ R1+ R2)/R2 × Vfb, R1 ═ 10K Ω, R2 ═ 2.21K Ω is arranged, the output voltage is 3.3V, VCC of MPQ8633 is 3V, and for the purpose of fast start-up, a fourth resistor R3 ═ 0 Ω to 10 Ω is selected, wherein the fifth resistor R4 is not mounted, and Q1 is NMOS-PMV16XNR, so that when the system is started up, Vgs of Q1 is VCC 3V, Q1 operates in the variable resistance region, and VR FB sense output voltage is rapidly raised, and when the value of the output voltage Vout reaches vth-VCC (gs) — (3-0.65 ═ 2.35V, Q1 is turned off. At this time, the voltage at the point a is the average voltage value of the total load output by the adjusting module 2, and the MPQ8633 adjusts in real time according to the voltage value at the point a to meet the operation requirement of the load.

Therefore, in the embodiment of the invention, a sense line is respectively led out from each load, each input end of the adjusting module is respectively connected with one sense line, the output end of the adjusting module is connected with the feedback end of the power module, the adjusting module can obtain the average voltage value of each load and transmit the average voltage value to the power module through the feedback end, and the average voltage value is fed back to the FB end through the divider resistor in the power module, so that the voltage of the FB end is obtained based on the average voltage value of each load, and the load is prevented from being damaged and the output voltage of the power module exceeds the IC required range when the current on a certain load changes, and the system works normally.

On the basis of the above embodiment, the embodiment of the present invention further provides a power supply system, which includes a power module and the voltage calibration circuit under the multi-load operation; the power module comprises a power module and a voltage division module, the voltage division module comprises a first voltage division resistor and a second voltage division resistor, the first end of the first voltage division resistor is connected with the first end of the second voltage division resistor, the common end of the first voltage division resistor is connected with the FB end of the power module, the second end of the first voltage division resistor is used as the feedback end of the power module and is connected with the output end of the adjusting module in the voltage calibration circuit under the multi-load operation, and the second end of the second voltage division resistor is grounded.

Specifically, the schematic structural diagram of the power supply system in the embodiment of the present invention may also refer to fig. 3 to fig. 5 in the above embodiment, and details of the embodiment of the present invention are not repeated here, which has the same beneficial effects as the voltage calibration circuit in the embodiment under multi-load operation.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

It is further noted that, in the present specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.