MCU power supply control circuit, controller and electric furniture of linear drive device

Abstract

The utility model discloses a kind of MCU power supply control circuit of linear drive device, controller and electric furniture, for realizing the zero power consumption standby of MCU and load wake-up.The technical scheme is: in standby state, MCU is completely powered off, but a DC output port remains electrified.When external load is connected to the DC output port and generates current, a passive detection circuit consisting of sampling unit and detection unit generates trigger signal, the trigger signal turns on a first switching unit, thereby connecting the power supply of MCU, wakes up MCU to perform subsequent tasks.The utility model triggers MCU power-on by passive detection mode, completely solves the standby power consumption problem of equipment, simple structure, response sensitive.

Description

Technical Field

[0001] This utility model relates to the field of electronic control technology, and in particular to an MCU power supply control circuit for a linear drive device, as well as a controller and electric furniture including the circuit. Background Technology

[0002] Modern home and office equipment, such as smart height-adjustable desks, typically incorporate microcontrollers (MCUs) to enable complex logic control, human-computer interaction, and state memory functions. To enhance the user experience, these devices usually require standby functionality, meaning that when not performing primary functions (such as height adjustment), some circuitry remains powered to quickly respond to user input or charge external devices (such as mobile phones).

[0003] In traditional solutions, the MCU typically needs to be continuously powered to achieve standby functionality. Even in sleep or low-power modes, the entire control system still experiences significant static power consumption. Over extended standby periods, this accumulated energy consumption becomes substantial, contradicting the principles of green and energy-efficient design.

[0004] Another approach is to completely power off the device when in standby mode, waking it up via a mechanical physical switch. However, this reduces the product's intelligence and ease of use. For example, users might want the integrated USB charging port to remain usable in standby mode on a height-adjustable desk, and for the entire system to automatically wake up when a device is plugged in for charging—something traditional mechanical switch solutions cannot achieve.

[0005] Therefore, how to design a control circuit that can achieve "zero power consumption" or "microampere-level" power consumption in standby mode, while intelligently sensing the connection of external loads and automatically waking up the MCU, is a technical problem that urgently needs to be solved in the field of linear drive devices. Utility Model Content

[0006] The present invention aims to solve the technical problems of high power consumption of existing linear drive device controllers in standby mode and difficulty in achieving a balance between ultra-low power standby and intelligent wake-up.

[0007] The MCU power supply control circuit for the linear drive device provided by this utility model includes:

[0008] Power input terminal;

[0009] A DC output port, coupled to the power input terminal, is used to maintain DC voltage in standby mode and supply external loads.

[0010] A sampling unit, coupled to the DC output port, is used to acquire the current passing through the DC output port and generate a sampling signal;

[0011] A detection unit, coupled to the sampling unit, is used to receive the sampling signal and output a trigger signal when the sampling signal reaches a preset threshold.

[0012] The first switching unit is located between the MCU power supply and the MCU power supply terminal. It is used to turn on when the trigger signal is received, so as to apply the voltage of the MCU power supply to the MCU power supply terminal, thereby waking up the MCU.

[0013] Preferably, the sampling unit includes a sampling resistor, with a first end of the sampling resistor coupled to the DC output port and a second end of the sampling resistor coupled to a reference potential.

[0014] Preferably, the detection unit includes a first transistor, the control electrode of the first transistor is coupled to a first end of the sampling resistor, and the conductive path of the first transistor is coupled between the trigger signal output node and the reference potential. When the voltage across the sampling resistor reaches the conduction threshold of the first transistor, the first transistor is turned on and outputs the trigger signal at the trigger signal output node.

[0015] Preferably, the first switching unit includes a second transistor, the conductive path of the second transistor is coupled between the MCU power supply and the power supply terminal of the MCU, and the control electrode of the second transistor is coupled to the trigger signal output node.

[0016] Preferably, the sampling unit is also coupled to the sampling input port of the MCU so that the MCU can detect the current of the DC output port in real time after being woken up.

[0017] Preferably, the MCU power supply control circuit further includes:

[0018] The second switching unit is disposed between the power input terminal and the DC output port, and is used to control the power supply from the power input terminal to the DC output port.

[0019] The driving unit is coupled to the control node of the MCU and the second switching unit, and is used to drive the second switching unit to turn on or off according to the control signal output by the MCU.

[0020] Preferably, the second switching unit includes a MOSFET, the conductive path of which is coupled between the power input terminal and the DC output port, and the control electrode of the MOSFET serves as the control node.

[0021] Preferably, the driving unit includes a third transistor and a fourth transistor;

[0022] The conductive path of the third transistor is coupled between the control electrode of the fourth transistor and the reference potential, and the control electrode of the third transistor receives the control signal output by the MCU.

[0023] The conductive path of the fourth transistor is coupled between the power input terminal and the control node, and the control electrode of the fourth transistor is coupled to the conductive path of the third transistor, which is used to turn on when the third transistor is turned off and pull the potential of the control node towards the power input terminal.

[0024] The controller provided by this utility model includes the aforementioned MCU power supply control circuit.

[0025] The electric furniture provided by this utility model includes a linear drive device, as well as the MCU power supply control circuit or the controller.

[0026] One or more technical solutions provided in this utility model have at least the following technical effects or advantages:

[0027] 1) In standby mode, the core controller MCU is not powered at all, and the power consumption is close to zero. Only a microampere-level passive detection circuit composed of discrete components is working, which greatly reduces the static power consumption of the product.

[0028] 2) No user button is required. When a load is connected to the DC output port (such as a USB charging port) and current is generated, the circuit can automatically detect the current and generate a trigger signal to turn on the MCU power supply, thereby waking up the MCU and putting it into normal working state.

[0029] 3) Once awakened, the MCU can immediately take over control of the entire system. It can not only monitor the load current in real time and accurately through its own ADC port to achieve advanced functions such as overcurrent protection, but also control the on / off state of the main power supply circuit according to preset logic, improving the system's control flexibility and safety.

[0030] 4) The entire wake-up circuit is mainly composed of transistors and resistors / capacitors. Compared with using a dedicated low-power coprocessor or a complex power management chip, the solution in this application is lower in cost and higher in reliability. Attached Figure Description

[0031] Figure 1 This is a functional block diagram of the MCU power supply control circuit in one embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the MCU power supply control circuit in one embodiment of the present invention.

[0033] In the diagram: 1-Power input terminal; 2-Second switching unit; 3-DC output port; 4-MCU sampling input port; 5-MCU power supply; 6-MCU signal output port; 7-Drive unit; 8-Sampling unit; 9-Detection unit; 10-First switching unit; 11-MCU power supply port; Q1-First transistor; Q2-Second transistor; Q3-Third transistor; Q4-Fourth transistor; Q5-P-channel MOSFET; R1-Sampling resistor; D1-Isolation diode. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0035] like Figure 1 and Figure 2 As shown, this embodiment discloses an MCU power supply control circuit for a linear drive device. In a preferred embodiment, this circuit is applied to the controller of a height-adjustable desk.

[0036] The initial state is standby mode, during which the MCU is powered off, and its MCU signal output port 6 is in a low level or high impedance state. According to this embodiment, the power input terminal 1 is connected to a DC power supply, for example, 29V. The switching of this 29V voltage is controlled by the second switching unit 2, the core of which is a P-channel MOSFET Q5, whose switching is controlled by the driving unit 7 (mainly including the third transistor Q3 and the fourth transistor Q4).

[0037] In standby mode, since the MCU is powered off, MCU signal output port 6 outputs a low level. This low level is applied to the base of the NPN type third transistor Q3, causing it to be in the off state.

[0038] When the third transistor Q3 is off, it does not affect the potential of its collector. At this time, the base of the PNP-type fourth transistor Q4 is connected to the 29V power supply through a pull-up resistor. Therefore, the base potential of the fourth transistor Q4 is approximately equal to its emitter potential (both 29V), and its base-emitter junction cannot be forward biased, causing the fourth transistor Q4 to also be in the off state.

[0039] When the fourth transistor Q4 is off, it does not supply a 29V power supply voltage to the gate of the P-channel MOSFET Q5. At this time, the gate of the P-channel MOSFET Q5 is pulled low by a resistor divider (e.g., pulled low to 50% of the power supply voltage by two resistors). The source of the P-channel MOSFET Q5 is connected to the 29V power supply, while its gate is pulled low, resulting in a gate-source voltage VGS that is a very large negative value (e.g., -14.5V), thus fully turning on the P-channel MOSFET Q5.

[0040] After the P-channel MOSFET Q5 is turned on, the 29V voltage at power input terminal 1 is stably applied to DC output port 3. This DC output port 3 can be a USB charging port or other interface requiring standby power. At this time, since the MCU is not working, only the microampere-level detection circuit is operating, and the power consumption of the core part of the entire controller is extremely low.

[0041] When an external load (such as a mobile phone) is connected to DC output port 3, current will flow from DC output port 3 through the load and then return to the reference potential (ground) through sampling unit 8. Sampling unit 8 mainly includes a sampling resistor R1. Current flowing through sampling resistor R1 will generate a voltage drop V across it. R1 .

[0042] The voltage V R1 The current is applied to the control electrode (base) of the first transistor Q1, the core component of the detection unit 9. As the load current gradually increases, V... R1 When the value reaches the conduction threshold of the first transistor Q1 (typically 0.6V-0.7V for silicon transistors), the first transistor Q1 switches from the off state to the on state.

[0043] After the first transistor Q1 is turned on, it will quickly pull the potential of its collector to the reference potential (ground), thereby outputting a low-level trigger signal at the trigger signal output node (i.e., the collector of the first transistor Q1).

[0044] The trigger signal is transmitted to the first switching unit 10. The first switching unit 10 includes a second transistor Q2 (a PNP transistor in this example). A low-level trigger signal is applied to the base of the second transistor Q2, turning it on.

[0045] After the second transistor Q2 is turned on, an independent, pre-prepared MCU power supply 5 is connected to the MCU power supply port 11. This MCU power supply 5 is a stable power supply, for example, 5.7V, obtained by stepping down the 29V voltage from the power input terminal 1 via internal circuitry (such as an LDO or DC-DC converter). The turning on of the second transistor Q2 is equivalent to closing a switch. The 5.7V voltage passes through the second transistor Q2 and an optional isolation diode D1, and is finally applied to the MCU power supply port 11. The MCU receives power and is awakened, beginning to execute its internal program.

[0046] Once the MCU is woken up, it immediately enters normal working mode and takes over control of the entire system.

[0047] First, the MCU can be directly connected to the high-potential end of the sampling resistor R1 via its own MCU sampling input port 4 (usually an ADC analog-to-digital converter port). This allows the MCU to monitor the current flowing through the DC output port 3 in real time with high precision. Based on this accurate current reading, the MCU can implement more complex control logic, such as overcurrent protection and charging completion detection.

[0048] Secondly, the MCU can control the drive unit 7 through MCU signal output port 6, thereby actively controlling the on / off state of the P-channel MOSFET Q5. The specific process is as follows:

[0049] 1) To turn off the P-channel MOSFET Q5: The MCU outputs a high level from MCU signal output port 6. This high level turns on the third transistor Q3. After the third transistor Q3 turns on, its collector is pulled to ground, thereby pulling down the base potential of the fourth transistor Q4. Since the emitter of the fourth transistor Q4 is at 29V, the base being pulled low forward biases its base-emitter junction, and the fourth transistor Q4 turns on. After the fourth transistor Q4 turns on, a high voltage of 29V is applied to the gate of the P-channel MOSFET Q5. At this time, the gate and source potentials of Q5 are approximately equal (VGS≈0V), causing the P-channel MOSFET Q5 to turn off, thereby cutting off the main power supply circuit to the DC output port 3;

[0050] 2) To restart the P-channel MOSFET Q5: The MCU outputs a low level from MCU signal output port 6, the circuit returns to the standby state, and finally turns on the P-channel MOSFET Q5.

[0051] In summary, this invention achieves ultra-low power consumption in the standby state of the linear drive device through a clever circuit combining passive detection and active control, and can be intelligently woken up by an external load. After the MCU is woken up, it can seamlessly take over all control of the system, achieving an optimal balance between power consumption, functionality, and cost.

[0052] This utility model also protects a controller that includes any of the above-mentioned MCU power supply control circuits, and protects an electric furniture that includes any of the above-mentioned MCU power supply control circuits or includes the above-mentioned controller. Electric furniture generally refers to products equipped with linear drive devices (such as electric push rods), specifically including height-adjustable desks, electric sofas, electric beds, etc. In the application of height-adjustable desks, the DC output port 3 can be a USB charging port integrated on the desktop. Users can activate the entire height-adjustable desk system by inserting a mobile phone for charging, enabling functions such as memory position and height display, greatly improving the user experience.

Claims

1. A MCU power supply control circuit for a linear drive device, characterized in that, include: Power input terminal; A DC output port, coupled to the power input terminal, is used to maintain DC voltage in standby mode and supply external loads. A sampling unit, coupled to the DC output port, is used to acquire the current passing through the DC output port and generate a sampling signal; A detection unit, coupled to the sampling unit, is used to receive the sampling signal and output a trigger signal when the sampling signal reaches a preset threshold. The first switching unit is located between the MCU power supply and the MCU power supply terminal. It is used to turn on when the trigger signal is received, so as to apply the voltage of the MCU power supply to the MCU power supply terminal, thereby waking up the MCU.

2. The MCU supply control circuit of claim 1, wherein, The sampling unit includes a sampling resistor, with a first end of the sampling resistor coupled to the DC output port and a second end of the sampling resistor coupled to a reference potential.

3. The MCU supply control circuit of claim 2, wherein, The detection unit includes a first transistor, the control electrode of the first transistor is coupled to a first end of the sampling resistor, and the conductive path of the first transistor is coupled between the trigger signal output node and the reference potential. When the voltage across the sampling resistor reaches the conduction threshold of the first transistor, the first transistor is turned on and outputs the trigger signal at the trigger signal output node.

4. The MCU supply control circuit of claim 3, wherein, The first switching unit includes a second transistor, the conductive path of the second transistor is coupled between the MCU power supply and the power supply terminal of the MCU, and the control electrode of the second transistor is coupled to the trigger signal output node.

5. The MCU supply control circuit of claim 1, wherein, The sampling unit is also coupled to the sampling input port of the MCU so that the MCU can detect the current of the DC output port in real time after being woken up.

6. The MCU supply control circuit of claim 1, wherein, The MCU power supply control circuit also includes: The second switching unit is disposed between the power input terminal and the DC output port, and is used to control the power supply from the power input terminal to the DC output port. The driving unit is coupled to the control node of the MCU and the second switching unit, and is used to drive the second switching unit to turn on or off according to the control signal output by the MCU.

7. The MCU supply control circuit of claim 6, wherein, The second switching unit includes a MOSFET, the conductive path of which is coupled between the power input terminal and the DC output port, and the control electrode of the MOSFET serves as the control node.

8. The MCU supply control circuit of claim 6 or 7, wherein, The driving unit includes a third transistor and a fourth transistor; The conductive path of the third transistor is coupled between the control electrode of the fourth transistor and the reference potential, and the control electrode of the third transistor receives the control signal output by the MCU. The conductive path of the fourth transistor is coupled between the power input terminal and the control node, and the control electrode of the fourth transistor is coupled to the conductive path of the third transistor, which is used to turn on when the third transistor is turned off and pull the potential of the control node towards the power input terminal.

9. A controller characterized by comprising: Includes the MCU power supply control circuit as described in any one of claims 1 to 8.

10. An electrically powered furniture comprising a linear drive, characterized in that It also includes the MCU power supply control circuit according to any one of claims 1 to 8, or the controller according to claim 9.

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