阅读说明：本技术 一种控制电路 (Control circuit ) 是由 王长领 周海民 刘丹 于 2020-07-14 设计创作，主要内容包括：本发明公开了一种控制电路。该发明包括：第一电路板,用于输出第一电压；电压转换电路,与第一电路板电连接,电压转换电路用于将第一电路板输出的第一电压转换为第二电压,其中,第二电压小于第一电压；第二电路板,与电压转换电路电连接,第二电路板用于接收第二电压并基于第二电压工作。通过本发明,解决了相关技术中主板给子板供电时,导致跨板供电电压大幅波动的问题。(The invention discloses a control circuit. The invention comprises the following steps: a first circuit board for outputting a first voltage; the voltage conversion circuit is electrically connected with the first circuit board and is used for converting a first voltage output by the first circuit board into a second voltage, wherein the second voltage is smaller than the first voltage; and the second circuit board is electrically connected with the voltage conversion circuit and is used for receiving a second voltage and working based on the second voltage. According to the invention, the problem of large fluctuation of the cross-board power supply voltage when the main board supplies power to the daughter board in the related technology is solved.)

1. A control circuit, comprising:

a first circuit board for outputting a first voltage;

the voltage conversion circuit is electrically connected with the first circuit board and is used for converting the first voltage output by the first circuit board into a second voltage, wherein the second voltage is smaller than the first voltage;

and the second circuit board is electrically connected with the voltage conversion circuit and is used for receiving the second voltage and working based on the second voltage.

2. The control circuit of claim 1, wherein the voltage conversion circuit comprises:

the first chip comprises a first pin and a second pin, the first pin is electrically connected with the first circuit board, and the second pin is electrically connected with the second circuit board.

3. The control circuit of claim 1, wherein the second circuit board comprises:

the voltage monitoring sub-circuit is electrically connected with the voltage conversion circuit and is used for judging whether the second voltage is in a preset voltage range or not;

and the load sub-circuit is electrically connected with the voltage monitoring sub-circuit, and the voltage monitoring sub-circuit controls the load sub-circuit to be out of operation under the condition that the second voltage is not in the preset voltage range.

4. The control circuit of claim 3, wherein the voltage monitoring subcircuit comprises:

a first resistance unit including at least one resistance;

one end of the second resistance unit is electrically connected with the voltage monitoring sub-circuit, the other end of the second resistance unit is connected with the first resistance unit in series, and the second resistance unit at least comprises one resistor;

one end of the second chip is connected to a branch circuit between the first resistance unit and the second resistance unit;

and one end of the switch unit is electrically connected with the output end of the second chip, and the other end of the switch unit is electrically connected with the load sub-circuit.

5. The control circuit according to claim 4, wherein the second chip includes a third pin, the third pin is connected to a branch between the first resistance unit and the second resistance unit, the second chip is configured to obtain a third voltage and determine whether the third voltage is greater than a threshold voltage, when the third voltage is greater than the threshold voltage, the output terminal of the second chip sends a control signal to the switch unit, and the switch unit is turned off after receiving the control signal.

6. The control circuit of claim 5, wherein the second chip is a TL431 chip.

7. The control circuit according to claim 5, wherein the switching unit comprises:

one end of the first switch is connected with the output end of the second chip and used for receiving the control signal and turning off the first switch after receiving the control signal;

and one end of the second switch is connected with the output end of the first switch, and the other end of the second switch is connected with the load sub-circuit and is used for switching off after the first switch is detected to be switched off.

8. The control circuit of claim 7, wherein at least one MOS transistor is included in the first switch or the second switch.

9. The control circuit of claim 3, wherein the second circuit board further comprises:

and one end of the preset switch is connected with the voltage monitoring sub-circuit, the voltage monitoring sub-circuit does not work under the condition that the preset switch is closed, and the voltage monitoring sub-circuit works under the condition that the preset switch is turned off.

10. An electronic device comprising a control circuit, characterized in that the control circuit is a control circuit according to any one of claims 1 to 9.

Technical Field

The invention relates to the field of electronic circuit design, in particular to a control circuit.

Background

Disclosure of Invention

The main objective of the present invention is to provide a control circuit to solve the problem of large fluctuation of the supply voltage across the board when the main board supplies power to the daughter board in the related art.

To achieve the above object, according to one aspect of the present invention, a control circuit is provided. The control circuit includes: a first circuit board for outputting a first voltage; the voltage conversion circuit is electrically connected with the first circuit board and is used for converting a first voltage output by the first circuit board into a second voltage, wherein the second voltage is smaller than the first voltage; and the second circuit board is electrically connected with the voltage conversion circuit and is used for receiving a second voltage and working based on the second voltage.

Further, the voltage conversion circuit includes: the first chip comprises a first pin and a second pin, the first pin is electrically connected with the first circuit board, and the second pin is electrically connected with the second circuit board.

Further, the second circuit board includes: the voltage monitoring sub-circuit is electrically connected with the voltage conversion circuit and is used for judging whether the second voltage is in a preset voltage range or not; and the load sub-circuit is electrically connected with the voltage monitoring sub-circuit, and the voltage monitoring sub-circuit controls the load sub-circuit not to work under the condition that the second voltage is not in the preset voltage range.

Further, the voltage monitoring sub-circuit includes: a first resistance unit including at least one resistance; one end of the second resistance unit is electrically connected with the voltage monitoring sub-circuit, the other end of the second resistance unit is connected with the first resistance unit in series, and the second resistance unit at least comprises one resistor; one end of the second chip is connected to a branch circuit between the first resistance unit and the second resistance unit; and one end of the switch unit is electrically connected with the output end of the second chip, and the other end of the switch unit is electrically connected with the load sub-circuit.

Further, the second chip includes a third pin, the third pin is connected to a branch between the first resistance unit and the second resistance unit, the second chip is configured to obtain a third voltage and determine whether the third voltage is greater than a threshold voltage, when the third voltage is greater than the threshold voltage, an output end of the second chip sends a control signal to the switch unit, and the switch unit is turned off after receiving the control signal.

Further, the second chip is a TL431 chip.

Further, the switching unit includes: one end of the first switch is connected with the output end of the second chip and used for receiving the control signal and turning off the first switch after receiving the control signal; and one end of the second switch is connected with the output end of the first switch, and the other end of the second switch is connected with the load sub-circuit and is used for being turned off after the first switch is detected to be turned off.

Further, the first switch or the second switch at least comprises one MOS tube.

Further, the second circuit board further includes: and one end of the preset switch is connected with the voltage monitoring sub-circuit, the voltage monitoring sub-circuit does not work under the condition that the preset switch is closed, and the voltage monitoring sub-circuit works under the condition that the preset switch is turned off.

In order to achieve the above object, according to another aspect of the present invention, an electronic apparatus is provided. The electronic device includes: the control circuit is described above.

According to the invention, the following structure is adopted: a first circuit board for outputting a first voltage; the voltage conversion circuit is electrically connected with the first circuit board and is used for converting a first voltage output by the first circuit board into a second voltage, wherein the second voltage is smaller than the first voltage; the second circuit board is electrically connected with the voltage conversion circuit and used for receiving second voltage and working based on the second voltage, the problem that cross-board power supply voltage fluctuates greatly when the mainboard supplies power to the daughter boards in the related technology is solved, and the technical effect of normal and stable working of the multi-board system is achieved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a control circuit provided in accordance with an embodiment of the present invention;

FIG. 2 is a schematic diagram of a motherboard providing 5V voltage and a daughter board providing 3.3V voltage via a voltage conversion circuit 20;

fig. 3 is a schematic diagram of another motherboard providing 5V voltage and providing 3.3V voltage to the daughter board through the voltage conversion circuit 20 provided by the present application; and

fig. 4 is a schematic diagram of a second circuit board 30 (sub-board) according to an embodiment of the present disclosure.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to make the technical solutions of the present invention better understood, 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 only a part of the embodiments of the present invention, and not all of the embodiments. 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.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged under appropriate circumstances in order to facilitate the description of the embodiments of the invention herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

According to an embodiment of the present invention, there is provided a control circuit.

Fig. 1 is a schematic diagram of a control circuit according to an embodiment of the present invention. As shown in fig. 1, the circuit includes the following structure: a first circuit board 10, a voltage conversion circuit 20, and a second circuit board 30.

Specifically, a first circuit board 10 for outputting a first voltage;

specifically, the voltage conversion circuit 20 is electrically connected to the first circuit board 10, and the voltage conversion circuit 20 is configured to convert a first voltage output by the first circuit board 10 into a second voltage, where the second voltage is smaller than the first voltage;

specifically, the second circuit board 30 is electrically connected to the voltage conversion circuit 20, and the second circuit board 30 is configured to receive a second voltage and operate based on the second voltage.

Above-mentioned, through install voltage converting circuit 20 additional between daughter board and mainboard, realized converting the high level that the mainboard provided into the required low level's of daughter board purpose to guaranteed the steady operation of system, wherein, the mainboard user provides the high level, and the daughter board is used for receiving the low-voltage after voltage converting circuit 20 converts, and in this embodiment, first circuit board 10 is the mainboard, and second circuit board 30 is the daughter board.

The control circuit provided by the embodiment of the invention is used for outputting a first voltage through the first circuit board 10; the voltage conversion circuit 20 is electrically connected with the first circuit board 10, and the voltage conversion circuit 20 is used for converting a first voltage output by the first circuit board 10 into a second voltage, wherein the second voltage is smaller than the first voltage; the second circuit board 30 is electrically connected to the voltage conversion circuit 20, and the second circuit board 30 is configured to receive a second voltage and operates based on the second voltage, so that a problem that a cross-board power supply voltage fluctuates greatly when the main board supplies power to the daughter boards in the related art is solved, and a technical effect of normal and stable operation of the multi-board system is achieved.

Alternatively, the voltage conversion circuit 20 includes: the first chip includes a first lead electrically connected to the first circuit board 10 and a second lead electrically connected to the second circuit board 30.

Specifically, the voltage conversion circuit 20 is a voltage conversion chip, and includes a first pin and a second pin, where the first pin is connected to the main board and is configured to receive a high voltage provided by the main board, and the second pin is connected to the daughter board and is configured to output a low voltage required by the daughter board, where the voltage conversion chip converts the high level into the low level.

Fig. 2 is a schematic diagram of the motherboard providing 5V voltage and the voltage conversion circuit 20 providing 3.3V voltage to the daughter board, the circuit is a common 3.3V voltage regulator circuit, and when the input voltage of the 3 pin is 5V, the output voltage of the 2 pin is 3.3V.

Specifically, when the daughter board needs 3.3V, 5V voltage can be directly introduced into the daughter board from the main board, and the voltage is reduced to 3.3V through the U15 chip for the daughter board to use, so that the problem of interference of the 5V voltage caused by board crossing can be filtered out, and the working stability of the daughter board is improved.

It should be noted that the type of the buck chip can be freely adjusted according to the voltage class requirements of the specific system and daughter board.

Fig. 3 is a schematic diagram of another motherboard providing 5V voltage and providing 3.3V voltage to a daughter board through a voltage conversion circuit 20, where the voltage conversion chip is a U1 chip, and if the 6-pin power supply voltage is 3.3V and the 1-pin power supply voltage is 5V, when the input level of the chip pin 4 is 3.3V, the output level of the pin 3 is 5V, so as to implement the conversion of the cross-board level state.

It should be noted that, if the communication protocol of the daughter board is I2C, the 3.3V level standard can be converted into the 5V level standard through the circuit, and the 5V level standard is converted into the 3.3V standard through the same circuit on the motherboard side, so that the level standard transmitted between boards is 5V, which can correspondingly reduce data errors caused by interference during transmission between boards, wherein the voltage levels between boards and inside boards can be freely configured through pins 1 and 6 of the access U1 chip.

Optionally, the second circuit board 30 includes: a voltage monitoring sub-circuit electrically connected to the voltage converting circuit 20, the voltage monitoring sub-circuit being configured to determine whether the second voltage is within a preset voltage range; and the load sub-circuit is electrically connected with the voltage monitoring sub-circuit, and the voltage monitoring sub-circuit controls the load sub-circuit not to work under the condition that the second voltage is not in the preset voltage range.

Specifically, a voltage monitoring subcircuit is provided in the second circuit board 30 for providing a protection mechanism for the daughter board.

Specifically, the voltage monitoring sub-circuit monitors whether the second voltage provided to the daughter board through the voltage conversion circuit 20 is within a safe voltage range through the second chip, and if the second voltage is not within the safe voltage range, the voltage monitoring sub-circuit cuts off a load loop in the daughter board to provide a protection mechanism for the daughter board.

Optionally, the second chip is a TL431 chip, and the second chip provided herein is a TL431 chip.

Optionally, the voltage monitoring sub-circuit comprises: a first resistance unit including at least one resistance; one end of the second resistance unit is electrically connected with the voltage monitoring sub-circuit, the other end of the second resistance unit is connected with the first resistance unit in series, and the second resistance unit at least comprises one resistor; one end of the second chip is connected to a branch circuit between the first resistance unit and the second resistance unit; and one end of the switch unit is electrically connected with the output end of the second chip, and the other end of the switch unit is electrically connected with the load sub-circuit.

In the above, fig. 4 is a schematic diagram of the second circuit board 30 (daughter board) provided in the embodiment of the present application, where the voltage monitoring sub-circuit is disposed in the daughter board, and the voltage monitoring sub-circuit includes a second chip, a first resistance unit, a second resistance unit, and a switch unit, as shown in the figure, U60/TL431 is the second chip, R5 is the first resistance unit, R270 and R271 jointly form the second resistance unit, one end of the second resistance unit is connected to the first resistance unit, the other end of the second resistance unit is connected to the voltage monitoring sub-circuit, the switch unit includes Q21 and Q20, and preferably, at least one MOS transistor is included in the first switch or the second switch.

Optionally, the second chip includes a third pin, the third pin is connected to a branch between the first resistance unit and the second resistance unit, the second chip is configured to obtain a third voltage and determine whether the third voltage is greater than a threshold voltage, when the third voltage is greater than the threshold voltage, an output end of the second chip sends a control signal to the switch unit, and the switch unit is turned off after receiving the control signal.

Optionally, the switching unit comprises: one end of the first switch is connected with the output end of the second chip and used for receiving the control signal and turning off the first switch after receiving the control signal; and one end of the second switch is connected with the output end of the first switch, and the other end of the second switch is connected with the load sub-circuit and is used for being turned off after the first switch is detected to be turned off.

Specifically, as shown in fig. 4, the 2 pins of the second chip are connected between the first resistance unit and the second resistance unit, in this embodiment, a specific monitoring method for monitoring whether the low voltage provided by the main board for the daughter board through the voltage monitoring sub-circuit is within the voltage safety range includes: the second chip obtains the voltage input into the load circuit through the pin 2, and judges whether the third voltage of the pin 2 is greater than the threshold voltage, if the third voltage is not greater than the threshold voltage, the daughter board circuit works normally, and if the third voltage is greater than the threshold voltage, the voltage monitoring sub-circuit controls the load circuit of the daughter board to be switched off through the switch unit so as to protect the system.

The switch unit comprises a first switch and a second switch, and when the third voltage is greater than the threshold voltage, the second chip sends out an over-control signal, and the Q21 is turned off after receiving the over-control signal, so that the Q20 connected with the second chip is controlled to be turned off to cut off the load sub-circuit.

It should be noted that the voltage monitoring sub-circuit can be used on the high voltage input side to control the on/off of the large voltage and the large current, and can also be used on the low voltage input end (such as 3.3V), so as to solve the problem that the low voltage simple component is not easy to control. The circuit can control the threshold voltage of voltage protection (the resistance value of the monitored 2 pins and the resistance value monitored by the TL431 can be changed) by adjusting the resistance values of R5, R270 and R271, and further controls the conduction or non-conduction of Q21 by switching on and off the U60(TL431), thereby controlling the conduction or non-conduction of Q20.

In the embodiment provided by the application, the input power supply of the system mainboard is 12V, a voltage monitoring circuit formed by TL431 can be added to the 12V input end to realize the monitoring of the input voltage and protect the back electrode load, and the circuit can also flexibly design the protection threshold voltage, for example, the input voltage is not the conventional voltage class (8V, 10V). If the requirement on the stability of the daughter board is higher, the voltage can be correspondingly added into the daughter board, and the stability of the input voltage of the daughter board is ensured.

Another way to protect the daughter board is to add a voltage reduction circuit to the daughter board system without directly using the power supplied by the motherboard, such as: the voltage that the daughter board was used is 3.3V, then can lead to the daughter board with the 5V of mainboard or 12V voltage, reduces the voltage and reuse after 3.3V, and voltage conversion has certain steady voltage effect to 3.3V voltage.

Generally, the I2C and the SPI are not used for inter-board communication, but for some special systems with slow transmission rate or strictly controlled design cost, it is also applicable if the transmission data can be protected to be relatively stable, and the method in the above figure is to boost the level of the I2C protocol sent by the main control MCU to a voltage level of 5V or even higher, so that the possibility that the data line is affected in the transmission process can be reduced as much as possible in the inter-board transmission process.

Optionally, the second circuit board 30 further includes: and one end of the preset switch is connected with the voltage monitoring sub-circuit, the voltage monitoring sub-circuit does not work under the condition that the preset switch is closed, and the voltage monitoring sub-circuit works under the condition that the preset switch is turned off.

As shown in fig. 4, the system power-off can be controlled by a preset switch in the daughter board, wherein the preset switch is SW3, and Q20 is always turned off when SW3 turns to pin 1, thereby controlling the power-off of the whole system.

Through above-mentioned control circuit, solved and strided board supply voltage big fluctuation problem, better simultaneously solved I2C and SPI and strided the board transmission unstability problem, to having the board system of striding of I2C and SPI between the board, the designer need not consider again, the communication between the board is carried out again after the I2C protocol data of daughter board convert into protocols such as USART, has reduced software research and development time. The data transmission can be relatively more stable and reliable by directly raising the level standard of the I2C protocol.

In the above, the level standard of each protocol can be customized according to specific project and equipment working environment.

By adding the overvoltage protection circuit in the daughter board and the mainboard, the power supply of the daughter board can directly use the existing power supply of the mainboard, and different worry about interference caused by remote board-crossing transmission of the power supply can cause serious influence on the daughter board.

Meanwhile, the protection voltage value of the voltage monitoring can be freely adjusted according to specific conditions through a hardware circuit so as to adapt to different voltage levels.

It should also be noted that 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 the process, method, article, or apparatus that comprises the element.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The above are merely examples of the present invention, and are not intended to limit the present invention. Various modifications and alterations to this invention will become apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.