An intelligent energy-saving circuit and control method for a video mainboard

Abstract

The present invention discloses an intelligent energy-saving circuit and control method for a video main board, which relates to the technical field of electronic circuits. The DC buck circuit is a switching regulator that converts high-voltage direct current into low-voltage direct current; the first input terminal of the PWM voltage stabilization circuit is connected to the load output terminal, the second input terminal receives a preset modulation voltage signal, the third input terminal receives a main clock signal and a preset duty cycle, and the output terminal is connected to the switch; the preset duty cycle and the preset modulation voltage signal are related to the type of load device; the PD modulation circuit and the time compensation circuit generate a second control signal. Using a switching regulator to achieve the DC-DC function can reduce energy loss caused by device heating, and the PWM voltage stabilization circuit can control the duty cycle and switching frequency of the switch according to the type of load device, reducing the overall energy consumption. Moreover, the PWM voltage stabilization circuit can perform frequency division modulation and time delay compensation, reducing electromagnetic interference caused by the switch.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic circuits, and particularly to an intelligent energy-saving circuit and control method for a video mainboard. Background Art

[0002] A video mainboard is a type of computer mainboard dedicated to processing video signals and providing video output functions. It is usually installed in professional video processing devices or high-end gaming computers to meet the requirements for high-quality video output and processing.

[0003] The DC-DC converter on the video mainboard is an electronic device that converts the DC power supply from one voltage level to another. In the video mainboard, the DC-DC converter is usually used to provide the required power supply voltage for different components and subsystems. The DC-DC converter plays a crucial role in the video mainboard because it can provide stable and efficient power for the processor, memory, graphics processor, and other high-performance components. Since these components require different voltage and current levels to operate properly, the DC-DC converter needs to precisely control the output voltage and current to ensure the stability and performance of the system.

[0004] However, in the prior art, the efficiency of the DC-DC converter is low, resulting in excessive energy consumption of the video mainboard. Summary of the Invention

[0005] The object of the present invention is to solve the problem of excessive energy consumption of the video mainboard in the above background art, and to propose an intelligent energy-saving circuit and control method for a video mainboard.

[0006] The object of the present invention can be achieved by the following technical solutions:

[0007] An embodiment of the present invention provides an intelligent energy-saving circuit for a video mainboard, including a DC buck circuit and a PWM voltage stabilizing circuit; the DC buck circuit is a switching regulator; the PWM voltage stabilizing circuit includes a PD modulation circuit and a time compensation circuit;

[0008] The DC buck circuit is used to convert the high-voltage direct current at the voltage input end into the low-voltage direct current required by the video mainboard, and output the low-voltage direct current through the load output end;

[0009] The PWM voltage stabilizing circuit includes a first input end, a second input end, a third input end, and an output end. The first input end is connected to the load output end, the second input end receives a preset modulation voltage signal, the third input end receives the main clock signal and a preset duty cycle of the video mainboard, and the output end is connected to the switch in the DC buck circuit; the preset duty cycle and the preset modulation voltage signal are related to the type of load device;

[0010] The PD modulation circuit is configured to generate a first control signal based on the low-voltage direct current and a preset modulation voltage signal;

[0011] The time compensation circuit is configured to perform time delay compensation on the first control signal according to the master clock signal and the preset duty cycle to obtain a second control signal.

[0012] Optionally, the DC buck circuit includes a voltage input terminal and a load output terminal, inductors L1, L2, and L3, capacitors C1, C2, C3, and C4, diodes D1, D2, D3, and D4, and a switch S;

[0013] One end of L1 is respectively connected to the positive electrode of the voltage input terminal and the positive electrode of D1, the negative electrode of D1 is respectively connected to one end of C1 and the source electrode of S, the other end of C1 is respectively connected to one end of L2, the positive electrode of D2, and one end of C2, the negative electrode of D2 is respectively connected to one end of C3 and one end of L3, the other end of C2 is respectively connected to the other end of L3 and the positive electrode of D3, the other end of L2 is connected to the negative electrode of D4, the positive electrode of D4 is respectively connected to one end of C4 and one end of the load output terminal, the negative electrode of the voltage input terminal is respectively connected to the drain electrode of S, the other end of C3, the negative electrode of D3, the other end of C4, and the other end of the load output terminal, and the gate electrode of S is connected to the output terminal of the PWM voltage stabilizing circuit.

[0014] Optionally, the PD modulation circuit includes a low-pass filter circuit, a transconductance circuit, an oscillation circuit, and a PD controller; the transconductance circuit is configured to convert a voltage signal into a current signal, and the transconductance circuit includes a first positive input terminal, a second positive input terminal, a first negative input terminal, a second negative input terminal, a first positive output terminal, a second positive output terminal, a first negative output terminal, and a second negative output terminal for converting a voltage signal into a current signal;

[0015] The input terminal of the low-pass filter circuit is connected to the load output terminal, the output terminal of the low-pass filter circuit is connected to the first positive input terminal, the first negative input terminal receives a preset reference voltage, the second positive input terminal receives a preset modulation voltage signal, the second negative input terminal is grounded, the first positive output terminal is connected to the second positive output terminal as the first control terminal of the oscillation circuit, the first negative output terminal is connected to the second negative output terminal as the second control terminal of the oscillation circuit, the output terminal of the oscillation circuit is connected to the input terminal of the PD controller, and the output terminal of the PD controller is connected to the time compensation circuit.

[0016] Optionally, the oscillation circuit includes a first current-controlled oscillator and a second current-controlled oscillator. The control current input port of the first current-controlled oscillator is the first control end, and the control current input port of the second current-controlled oscillator is the second control end.

[0017] Optionally, the time compensation circuit includes a PWM controller and an accumulated error circuit; the accumulated error circuit includes a first parameter input end, a second parameter input end, and an error output end; the PWM controller includes a first modulation input end, a second modulation input end, and a modulation output end;

[0018] The first parameter input end receives the main clock signal, and the second parameter input end receives the preset duty cycle;

[0019] The second modulation input end is connected to the error output end, the first modulation input end is connected to the output end of the PD controller, and the modulation output end is connected to the gate of the S.

[0020] Optionally, the accumulated error circuit includes a multiplier, an adder, an accumulator register, a low-byte truncation module, and a displacement module;

[0021] The input ends of the multiplier are respectively the first parameter input and the second parameter input end, and the multiplier is connected to the first addition input end of the adder; the input end of the adder is connected to the input end of the accumulator register, the output end of the accumulator register is respectively connected to the low-byte truncation module and the displacement module, the other end of the low-byte truncation module is connected to the second addition input end of the adder, and the other end of the displacement module is connected to the error output end.

[0022] An embodiment of the present invention also provides a control method for an intelligent energy-saving circuit of a video main board, and the method includes:

[0023] Receiving a voltage output instruction sent by the video main board, obtaining the main clock signal and the preset modulation voltage signal of the video main board, and determining the preset duty cycle according to the voltage output instruction; the preset duty cycle is related to the device type corresponding to the voltage output instruction;

[0024] Sending the preset modulation voltage signal to the second input end, and sending the main clock signal and the preset duty cycle of the video main board to the third input end;

[0025] Turning on the DC buck circuit and the PWM voltage stabilizing circuit.

[0026] Optionally, the method includes:

[0027] Obtain the first switching frequency and the second switching frequency of the switch in the current period and the previous period;

[0028] If the difference between the first switching frequency and the second switching frequency is less than a preset threshold, turn off the cumulative error circuit.

[0029] Advantages of the present invention:

[0030] An embodiment of the present invention provides an intelligent energy-saving circuit for a video main board, including a DC buck circuit and a PWM voltage stabilizing circuit; the DC buck circuit is a switching regulator; the PWM voltage stabilizing circuit includes a PD modulation circuit and a time compensation circuit; the DC buck circuit is used to convert the high-voltage direct current at the voltage input end into the low-voltage direct current required by the video main board and output the low-voltage direct current through the load output end; the PWM voltage stabilizing circuit includes a first input end, a second input end, a third input end and an output end, the first input end is connected to the load output end, the second input end receives a preset modulation voltage signal, the third input end receives the main clock signal and a preset duty cycle of the video main board, and the output end is connected to the switch in the DC buck circuit; the preset duty cycle and the preset modulation voltage signal are related to the type of load device; the PD modulation circuit is used to generate a first control signal according to the low-voltage direct current and the preset modulation voltage signal; the time compensation circuit is used to perform time delay compensation on the first control signal according to the main clock signal and the preset duty cycle to obtain a second control signal. Using a switching regulator to implement the DC-DC function can reduce the energy loss caused by device heating, and the PWM voltage stabilizing circuit can control the duty cycle and switching frequency of the switch according to the type of load device, reducing the overall energy consumption, and the PWM voltage stabilizing circuit can perform frequency division modulation and time delay compensation, reducing the electromagnetic interference caused by the switch. Description of the Drawings

[0031] The present invention will be further described below with reference to the drawings.

[0032] Figure 1 It is the overall circuit diagram of an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention;

[0033] Figure 2 It is the DC buck circuit diagram of an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention;

[0034] Figure 3 It is the PD modulation circuit diagram of an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention;

[0035] Figure 4 It is the time compensation circuit diagram of an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention. Detailed Embodiments

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0037] An embodiment of the present invention provides an intelligent energy-saving circuit for a video main board. Refer to Figure 1 , Figure 1 which is the overall circuit diagram of an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention. The circuit includes a DC buck circuit and a PWM voltage stabilization circuit; the DC buck circuit is a switching regulator; the PWM voltage stabilization circuit includes a PD modulation circuit and a time compensation circuit;

[0038] The DC buck circuit is used to convert the high-voltage direct current at the voltage input end into the low-voltage direct current required by the video main board and output the low-voltage direct current through the load output end;

[0039] The PWM voltage stabilization circuit includes a first input end, a second input end, a third input end and an output end. The first input end is connected to the load output end, the second input end receives a preset modulation voltage signal, the third input end receives the main clock signal and a preset duty cycle of the video main board, and the output end is connected to the switch in the DC buck circuit; the preset duty cycle and the preset modulation voltage signal are related to the type of load device;

[0040] The PD modulation circuit is used to generate a first control signal according to the low-voltage direct current and the preset modulation voltage signal;

[0041] The time compensation circuit is used to perform time delay compensation on the first control signal according to the main clock signal and the preset duty cycle to obtain a second control signal.

[0042] Based on the intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention, a switching regulator is used to implement the DC-DC function, which can reduce the energy loss caused by device heating. And the PWM voltage stabilization circuit can control the duty cycle and switching frequency of the switch according to the type of load device, reducing the overall energy consumption. And the PWM voltage stabilization circuit can perform frequency division modulation and time delay compensation, reducing the electromagnetic interference caused by the switch.

[0043] In one implementation, Figure 1 the high-voltage direct current at the voltage input end is VIN, the low-voltage direct current is VOUT, V(t) is the preset modulation voltage signal, K1 is the first control signal, T is the main clock signal, D is the preset duty cycle, and K2 is the second control signal.

[0044] In one embodiment, refer to Figure 2 , Figure 2This is a DC buck circuit diagram of an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention. The DC buck circuit includes a voltage input end and a load output end, inductors L1, L2, and L3, capacitors C1, C2, C3, and C4, diodes D1, D2, D3, and D4, and a switch S;

[0045] Both ends of L1 are respectively connected to the positive pole of the voltage input end and the positive pole of D1. The negative pole of D1 is respectively connected to one end of C1 and the source electrode of S. The other end of C1 is respectively connected to one end of L2, the positive pole of D2, and one end of C2. The negative pole of D2 is respectively connected to one end of C3 and one end of L3. The other end of C2 is respectively connected to the other end of L3 and the positive pole of D3. The other end of L2 is connected to the negative pole of D4. The positive pole of D4 is respectively connected to one end of C4 and one end of the load output end. The negative pole of the voltage input end is respectively connected to the drain electrode of S, the other end of C3, the negative pole of D3, the other end of C4, and the other end of the load output end. The gate electrode of S is connected to the output end of the PWM voltage stabilization circuit.

[0046] In one implementation, the above DC buck circuit diagram can achieve voltage gain in an ideal state. When the preset duty cycle D is less than 0.22, the purpose of bucking voltage can be achieved. The required VOUT can be determined according to the type of load device, the current voltage gain can be determined according to the current VIN, and then the preset duty cycle D can be calculated according to the above formula.

[0047] In one embodiment, refer to Figure 3 , Figure 3 This is a PD modulation circuit diagram of an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention. The PD modulation circuit includes a low-pass filter circuit, a transconductance circuit ( Figure 3 two voltage-current converters VCC in Figure 3 ), an oscillation circuit (

[0048] two current-controlled oscillators CCO in Figure 3 ), and a PD controller; the transconductance circuit is used to convert a voltage signal into a current signal. The transconductance circuit includes a first positive input end, a second positive input end, a first negative input end, a second negative input end, a first positive output end, a second positive output end, a first negative output end, and a second negative output end, and is used to convert a voltage signal into a current signal;

[0048] The input end of the low-pass filter circuit is connected to the load output end. The output end of the low-pass filter circuit is connected to the first positive input end. The first negative input end receives a preset reference voltage (VC). The second positive input end receives a preset modulation voltage signal. The second negative input end is grounded. The first positive output end is connected to the second positive output end as the first control end of the oscillation circuit. The first negative output end is connected to the second negative output end as the second control end of the oscillation circuit. The output end of the oscillation circuit is connected to the input end of the PD controller. The output end of the PD controller is connected to the time compensation circuit.

[0049] In one embodiment, the oscillation circuit includes a first current-controlled oscillator and a second current-controlled oscillator. The control current input port of the first current-controlled oscillator is the first control end, and the control current input port of the second current-controlled oscillator is the second control end.

[0050] In one embodiment, referring to Figure 4 , Figure 4 is the time compensation circuit diagram of an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention. The time compensation circuit includes a PWM controller and an accumulated error circuit; the accumulated error circuit includes a first parameter input end, a second parameter input end, and an error output end; the PWM controller includes a first modulation input end, a second modulation input end, and a modulation output end;

[0051] The first parameter input end receives the main clock signal, and the second parameter input end receives the preset duty cycle;

[0052] The second modulation input end is connected to the error output end, the first modulation input end is connected to the output end of the PD controller, and the modulation output end is connected to the gate of S.

[0053] In one embodiment, the accumulated error circuit includes a multiplier, an adder, an accumulator register, a low-byte truncation module, and a displacement module;

[0054] The input ends of the multiplier are respectively the first parameter input and the second parameter input end, and the multiplier is connected to the first addition input end of the adder; the input end of the adder is connected to the input end of the accumulator register, the output end of the accumulator register is respectively connected to the low-byte truncation module and the displacement module, the other end of the low-byte truncation module is connected to the second addition input end of the adder, and the other end of the displacement module is connected to the error output end.

[0055] In one implementation, Figure 4 the ΔT output by the displacement module is the calculated time delay.

[0056] An embodiment of the present invention provides a control method for an intelligent energy-saving circuit of a video main board. The method includes:

[0057] Receiving a voltage output instruction sent by the video main board, obtaining the main clock signal and the preset modulation voltage signal of the video main board, and determining the preset duty cycle according to the voltage output instruction; the preset duty cycle is related to the device type corresponding to the voltage output instruction;

[0058] Sending the preset modulation voltage signal to the second input end, and sending the main clock signal and the preset duty cycle of the video main board to the third input end;

[0059] Turning on the DC buck circuit and the PWM voltage stabilizing circuit.

[0060] Based on an intelligent energy-saving circuit for a video main board provided by an embodiment of the present invention, a switching regulator is used to implement the DC-DC function, which can reduce energy loss caused by device heating. And the PWM voltage regulation circuit can control the duty cycle and switching frequency of the switch according to the type of load device, reducing the overall energy consumption. Moreover, the PWM voltage regulation circuit can perform frequency division modulation and delay compensation, reducing the electromagnetic interference caused by the switch.

[0061] In one embodiment, the method further includes:

[0062] Obtain the first switching frequency and the second switching frequency of the switch in the current cycle and the previous cycle;

[0063] If the difference between the first switching frequency and the second switching frequency is less than a preset threshold, turn off the cumulative error circuit.

[0064] In one implementation, when the switching frequency changes greatly, the cumulative error circuit is turned on. At this time, the first control signal can be subjected to delay compensation to obtain a second control signal, and the switch is controlled by the second control signal; when the switching frequency changes little, the cumulative error circuit can be turned off, and the switch is controlled by the first control signal.

[0065] The above has described an embodiment of the present invention in detail, but the content described is only a preferred embodiment of the present invention and cannot be considered as limiting the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of the application of the present invention should still fall within the scope covered by the patent of the present invention.

Claims

1. A video mainboard intelligent energy-saving circuit, characterized in that: It includes a DC step-down circuit and a PWM voltage stabilization circuit; the DC step-down circuit is a switching regulator; the PWM voltage stabilization circuit includes a PD modulation circuit and a time compensation circuit; The DC step-down circuit is used to convert the high-voltage DC power at the voltage input terminal into the low-voltage DC power required by the video mainboard, and output the low-voltage DC power through the load output terminal; The PWM voltage stabilization circuit includes a first input terminal, a second input terminal, a third input terminal and an output terminal, wherein the first input terminal is connected to the load output terminal, the second input terminal receives a preset modulation voltage signal, the third input terminal receives a main clock signal of the video motherboard and a preset duty cycle, and the output terminal is connected to a switch in the DC step-down circuit; the preset duty cycle and the preset modulation voltage signal are related to the type of the load device; The PD modulation circuit is used to generate a first control signal according to the low-voltage direct current and a preset modulation voltage signal; The time compensation circuit is used to perform time delay compensation on the first control signal according to the main clock signal and the preset duty cycle to obtain a second control signal; The DC step-down circuit includes a voltage input terminal and a load output terminal, inductors L1, L2 and L3, capacitors C1, C2, C3 and C4, diodes D1, D2, D3 and D4, and a switch S; Two ends of L1 are respectively connected to the positive electrode of the voltage input end and the positive electrode of D1, the negative electrode of D1 is respectively connected to one end of C1 and the source electrode of S, the other end of C1 is respectively connected to one end of L2, the positive electrode of D2 and one end of C2, the negative electrode of D2 is respectively connected to one end of C3 and one end of L3, the other end of C2 is respectively connected to the other end of L3 and the positive electrode of D3, the other end of L2 is connected to the negative electrode of D4, the positive electrode of D4 is respectively connected to one end of C4 and one end of the load output end, the negative electrode of the voltage input end is respectively connected to the drain electrode of S, the other end of C3, the negative electrode of D3, the other end of C4 and the other end of the load output end, and the gate of S is connected to the output end of the PWM voltage stabilization circuit.

2. The video mainboard intelligent energy-saving circuit according to claim 1, characterized in that: The PD modulation circuit includes a low-pass filter circuit, a mutual conduction circuit, an oscillation circuit and a PD controller; the mutual conduction circuit is used to convert a voltage signal into a current signal, and the mutual conduction circuit includes a first positive input terminal, a second positive input terminal, a first negative input terminal, a second negative input terminal, a first positive output terminal, a second positive output terminal, a first negative output terminal and a second negative output terminal, and is used to convert a voltage signal into a current signal; The input end of the low-pass filter circuit is connected to the load output end, the output end of the low-pass filter circuit is connected to the first positive input end, the first negative input end receives a preset reference voltage, the second positive input end receives a preset modulation voltage signal, the second negative input end is grounded, the first positive output end is connected to the second positive output end as the first control end of the oscillation circuit, the first negative output end is connected to the second negative output end as the second control end of the oscillation circuit, the output end of the oscillation circuit is connected to the input end of the PD controller, and the output end of the PD controller is connected to the time compensation circuit.

3. The video mainboard intelligent energy-saving circuit according to claim 2, characterized in that: The oscillation circuit includes a first current-controlled oscillator and a second current-controlled oscillator. The control current input port of the first current-controlled oscillator is the first control end, and the control current input port of the second current-controlled oscillator is the second control end.

4. The video mainboard intelligent energy-saving circuit according to claim 2, characterized in that: The time compensation circuit includes a PWM controller and an accumulation error circuit; the accumulation error circuit includes a first parameter input terminal, a second parameter input terminal and an error output terminal; the PWM controller includes a first modulation input terminal, a second modulation input terminal and a modulation output terminal; The first parameter input terminal receives the main clock signal, and the second parameter input terminal receives the preset duty cycle; The second modulation input terminal is connected to the error output terminal, the first modulation input terminal is connected to the output terminal of the PD controller, and the modulation output terminal is connected to the gate of S.

5. The video mainboard intelligent energy-saving circuit according to claim 4, characterized in that: The cumulative error circuit includes a multiplier, an adder, an accumulator register, a low-order byte interception module and a displacement module; The input ends of the multiplier are respectively the first parameter input and the second parameter input ends, and the multiplier is connected to the first addition input end of the adder; the input end of the adder is connected to the input end of the accumulator register, and the output end of the accumulator register is respectively connected to the low-order byte interception module and the displacement module, the other end of the low-order byte interception module is connected to the second addition input end of the adder, and the other end of the displacement module is connected to the error output end.

6. A control method for a video mainboard intelligent energy-saving circuit based on any one of claims 4-5, characterized in that: The method comprises: Receiving a voltage output instruction sent by the video mainboard, acquiring a main clock signal of the video mainboard, and determining the preset duty cycle and the preset modulation voltage signal according to the voltage output instruction; the preset duty cycle and the preset modulation voltage signal are related to the type of load device corresponding to the voltage output instruction; Sending a preset modulation voltage signal to the second input terminal, and sending a master clock signal and a preset duty cycle of the video mainboard to the third input terminal; The DC step-down circuit and the PWM voltage stabilization circuit are turned on.

7. A control method for a video mainboard intelligent energy-saving circuit according to claim 6, characterized in that: The method comprises: Obtaining a first switching frequency and a second switching frequency of the switch in a current cycle and a previous cycle; If the difference between the first switching frequency and the second switching frequency is smaller than a preset threshold, the cumulative error circuit is turned off.

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