Voltage switching control circuit

Abstract

The utility model discloses a voltage switching control circuit, which is arranged on a main board provided with a central processing unit, and comprises a first power supply management chip, a voltage switching tube module and a divider resistor group, the divider resistor group comprises a first divider resistor and a second divider resistor, the voltage switching tube module comprises a first switching tube and a second switching tube, and the first switching tube is connected with the second switching tube. A switch node pin of the first power supply management chip is connected with a voltage output end, a thirteenth electrolytic capacitor and one end of a first feedback resistor through a first inductor, and the other end of the first feedback resistor is connected with a feedback input pin of the first power supply management chip. A feedback input pin of the first power supply management chip is connected with one end of the first divider resistor and one end of the second divider resistor, the central processing unit is connected with the other end of the first divider resistor through a first switching tube, and the central processing unit is connected with first power supply voltage through a third switching tube. And the other end of the second divider resistor is electrically connected between the first power supply voltage and the third switch tube through the second switch tube.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, and in particular to a voltage switching control circuit. Background Art

[0002] To save development time and costs, existing motherboards are mostly designed to accommodate different CPUs. However, different CPUs have different operating voltages, and the output voltage of the power supply on a traditional motherboard is constant, which cannot meet the operating voltage of all CPUs. This affects the normal operation of the CPU whose operating voltage and output voltage do not match. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a voltage switching control circuit to perform voltage switching and output according to a central processing unit.

[0004] To solve the above technical problems, the purpose of the present utility model is achieved through the following technical solutions: providing a voltage switching control circuit, which is installed on a motherboard equipped with a central processing unit and is electrically connected to the central processing unit. The voltage switching control circuit includes a first power supply management chip, a voltage switching switch tube module and a voltage dividing resistor group. The voltage dividing resistor group includes a first voltage dividing resistor and a second voltage dividing resistor. The voltage switching switch tube module includes a first switch tube and a second switch tube. The switch node pin of the first power supply management chip is connected to the voltage output terminal, the positive electrode of a thirteenth electrolytic capacitor with a negative electrode grounded, and one end of a first feedback resistor through a first inductor. The other end of the first feedback resistor is connected to the feedback input pin of the first power supply management chip. The feedback input pin of the first power supply management chip is respectively connected to one end of the first voltage dividing resistor and one end of the second voltage dividing resistor. The central processing unit is connected to the other end of the first voltage dividing resistor through the first switch tube. The central processing unit is connected to a first power supply voltage through a third switch tube. The other end of the second voltage dividing resistor is electrically connected between the first power supply voltage and the third switch tube through the second switch tube.

[0005] The beneficial technical effect of the present invention is that: the voltage switching control circuit of the present invention is provided by setting a voltage switching switch tube module including a first switch tube and a second switch tube connected to the central processing unit and a voltage dividing resistor group including a first voltage dividing resistor and a second voltage dividing resistor connected to the first switch tube and the second switch tube respectively, and the central processing unit is connected to the first power supply voltage through the third switch tube, and the second voltage dividing resistor connected to the first power supply management chip is electrically connected to the first power supply voltage and the third switch tube through the second switch tube. The central processing unit is connected to the first power supply management chip through the first switch tube via the first voltage dividing resistor, so as to utilize the voltage switching switch tube module to control the corresponding switch tube to be turned on according to the identification signal of the central processing unit on the motherboard received, so that the corresponding voltage dividing resistor and the first feedback resistor divide the voltage, and adjust the voltage converted and output by the first power management chip to the working voltage required by the central processing unit, meet the voltage requirements of the central processing unit, so that the central processing unit can work normally, and realize the voltage switching according to the model of the central processing unit on the motherboard, so that the motherboard can be compatible with central processing units corresponding to different working voltages, thereby improving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0007] Figure 1 A schematic diagram of a voltage switching control circuit according to an embodiment of the present invention;

[0008] Figure 2 A circuit schematic diagram of a voltage switching control circuit provided by an embodiment of the present utility model;

[0009] Figure 3 This is a circuit schematic diagram of an auxiliary voltage circuit of a voltage switching control circuit provided in another embodiment of the present invention. DETAILED DESCRIPTION

[0010] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0011] See also Figure 1 and Figure 2 , Figure 1A schematic diagram of a framework of a voltage switching control circuit provided in an embodiment of the present invention, wherein the voltage switching control circuit is installed on a motherboard provided with a central processing unit and is electrically connected to the central processing unit. The voltage switching control circuit includes a first power supply management chip PU3, a voltage switching switch tube module 11 and a voltage dividing resistor group 12, wherein the voltage dividing resistor group 12 includes a first voltage dividing resistor PR504 and a second voltage dividing resistor PR2566, and the voltage switching switch tube module 11 includes a first switch tube PQ88 and a second switch tube PQ10. The switch node pin PHASE of the first power supply management chip PU3 is connected to the positive terminal of the voltage output terminal +VCCIO_0 and the negative terminal of the thirteenth electrolytic capacitor PCE13 grounded after passing through the first inductor PL11. The first electrode is connected to one end of the first feedback resistor PR492, the other end of the first feedback resistor PR492 is connected to the feedback input pin VFB of the first power supply management chip PU3, the feedback input pin VFB of the first power supply management chip PU3 is respectively connected to one end of the first voltage-dividing resistor PR504 and one end of the second voltage-dividing resistor PR2566, the central processing unit is connected to the other end of the first voltage-dividing resistor PR504 through the first switch tube PQ88, the central processing unit is connected to the first power supply voltage through the third switch tube PQ91, and the other end of the second voltage-dividing resistor PR2566 is electrically connected between the first power supply voltage and the third switch tube PQ91 through the second switch tube PQ10.

[0012] Among them, the first power supply voltage can be 3V voltage, the first switch tube PQ88 and the second switch tube PQ10 are connected to the central processing unit to receive the identification signal of the central processing unit, and the identification signal is used to identify the identity information of the central processing unit. The identity information of the central processing unit includes the model, generation and other information of the central processing unit. Different central processing units have different operating voltages. By receiving the identification signal of the central processing unit, it is known whether the central processing unit on the motherboard has been replaced so as to perform voltage switching later. The voltage switching control circuit is provided by setting a voltage switching switch tube module 11 including a first switch tube PQ88 and a second switch tube PQ10 connected to the central processing unit and a voltage dividing resistor group 12 including a first voltage dividing resistor PR504 and a second voltage dividing resistor PR2566 connected to the first switch tube PQ88 and the second switch tube PQ10 respectively, and the central processing unit is connected to the first power supply voltage through the third switch tube PQ91, and the second voltage dividing resistor PR2566 connected to the first power supply management chip PU3 is electrically connected to the first power supply voltage and the third switch tube PQ91 through the second switch tube PQ10. The central processing unit is connected to the first power supply voltage through the third switch tube PQ91. The first switch tube PQ88 is connected to the first power supply management chip PU3 via the first voltage-dividing resistor PR504, so as to utilize the voltage switching switch tube module 11 to control the corresponding switch tube to be turned on according to the identification signal of the central processing unit on the motherboard received, so that the corresponding voltage-dividing resistor and the first feedback resistor divide the voltage, and adjust the voltage converted and output by the first power supply management chip PU3 to the operating voltage required by the central processing unit, meet the voltage requirements of the central processing unit, so that the central processing unit can work normally, and realize the voltage switching according to the model of the central processing unit on the motherboard, so that the motherboard can be compatible with central processing units corresponding to different operating voltages, thereby improving safety.

[0013] Specifically, in this embodiment, the first power supply management chip PU3 is a PWM power supply management chip of model UP1537P.

[0014] Specifically, in this embodiment, the resistance of the first voltage-dividing resistor PR504 is smaller than the resistance of the second voltage-dividing resistor PR2566. The resistance of the first feedback resistor PR492 is smaller than the resistance of the first voltage-dividing resistor PR504.

[0015] Specifically, in this embodiment, the first switching transistor PQ88, the second switching transistor PQ10, and the third switching transistor PQ91 are all MOS transistors. The central processing unit is connected to the gates of the third switching transistor PQ91 and the first switching transistor PQ88, respectively. The sources of the first switching transistor PQ88, the second switching transistor PQ10, and the third switching transistor PQ91 are all grounded. The drain of the third switching transistor PQ91 is connected to the first power supply voltage through the first connection resistor PR2567. The gate of the second switching transistor PQ10 is electrically connected between the first connection resistor PR2567 and the drain of the third switching transistor PQ91. The drain of the second switching transistor PQ10 is connected to the feedback input pin VFB of the first power management chip PU3 and the first feedback resistor PR492 via the second voltage divider resistor PR2566. The drain of the first switching transistor PU3 is connected to the feedback input pin VFB of the first power management chip PU3 and the first feedback resistor PR492 via the first voltage divider resistor PR504.

[0016] Specifically, in this embodiment, the high-end field control pin UGATE of the first power supply management chip PU3 is connected to the gate of the first high-end MOS transistor PQ1H1, the low-end field control pin LGATE of the first power supply management chip PU3 is connected to the gate of the first low-end MOS transistor PQ1L1, the drain of the first high-end MOS transistor PQ1H1 is connected to the voltage input terminal VIN, the source of the first high-end MOS transistor PQ1H1 is connected to the drain of the first low-end MOS transistor PQ1L1, one end of the first inductor PL11 and the switch node pin PHASE of the first power supply management chip PU3, and the source of the first low-end MOS transistor PQ1L1 is grounded.

[0017] Specifically, in this embodiment, the bootstrap power supply pin BOOT of the first power supply management chip PU3 is connected to the switch node pin PHASE of the first power supply management chip PU3, the source of the first high-end MOS tube PQ1H1, the drain of the first low-end MOS tube PQ1L1 and the first inductor PL11 through the first connection capacitor PC825.

[0018] Based on the above design, during operation, when the operating voltage required by the CPU on the motherboard is a higher voltage, the identification signal of the CPU is at a high level, the gate of the third switch tube is pulled high, the third switch tube is turned on, the gate of the second switch tube is pulled low, the second switch tube is turned off, the second voltage divider resistor is left floating and does not participate in voltage division, while the gate of the first switch tube is pulled high, the first switch tube is turned on, the first voltage divider resistor and the first feedback resistor divide the voltage, so that the voltage output end switches to output a higher voltage to meet the operating voltage required by the CPU connected to the motherboard at this time; when the operating voltage required by the CPU on the motherboard is a lower voltage, the identification signal of the CPU is at a low level, the gate of the first switch tube is pulled low, the first switch tube is turned off, the first voltage divider resistor is left floating and does not participate in voltage division, while the gate of the third switch tube is pulled low, the third switch tube is turned off, the gate of the second switch tube is pulled high, the second switch tube is turned on, the second voltage divider resistor and the first feedback resistor divide the voltage, so that the voltage output end switches to output a lower voltage to meet the operating voltage required by the CPU connected to the motherboard at this time.

[0019] Combine Figure 3 Specifically, in some embodiments, the voltage switching control circuit further includes an auxiliary voltage circuit, which includes a second power supply management chip PU6, a control switch tube Q67 and a third voltage-dividing resistor PR522. The switch node pin PHASE of the second power supply management chip PU6 is connected to the output terminal +VCCIO_1_2, the positive electrode of the fourteenth electrolytic capacitor PCE14 with the negative electrode grounded, and one end of the second feedback resistor PR512 through the second inductor PL12. The other end of the second feedback resistor PR512 is connected to the feedback input pin VFB of the second power supply management chip PU6. The feedback input pin VFB of the second power supply management chip PU6 is grounded through the third voltage-dividing resistor PR522. The control end of the control switch tube Q67 is connected to the central processing unit, the first end of the control switch tube Q67 is connected to the second power supply voltage, the second end of the control switch tube Q67 is connected to the enable pin EN of the second power supply management chip PU6, and the enable pin EN of the second power supply management chip PU6 is connected to the third power supply voltage. Among them, the second power supply voltage can be a 5V voltage. By setting an auxiliary voltage circuit including a control switch tube Q67 and a second power supply management chip, and the control end of the control switch tube Q67 is connected to the central processing unit, the first end of the control switch tube Q67 is connected to the second power supply voltage, and the second end of the control switch tube Q67 is connected to the enable pin EN of the second power supply management chip PU6 connected to the third power supply voltage, so as to control the state of the enable pin EN of the second power supply management chip PU6 according to the identification signal of the central processing unit on the motherboard received to control the operation of the second power supply management chip PU6, so as to further ensure the output of the required working voltage according to the central processing unit on the motherboard.

[0020] Specifically, in this embodiment, the control switch tube Q67 adopts a MOS tube with model number 2N7002, the first gate G1 of the control switch tube Q67 is connected to the central processing unit, the first source S1 and the second source S2 of the control switch tube Q67 are both grounded, and the second supply voltage is connected to the first drain D1 and the second gate G2 of the control switch tube Q67 respectively after passing through the second connection resistor R635, and the second drain D2 of the control switch tube Q67 is connected to the enable pin EN of the second power supply management chip PU6.

[0021] Specifically, in this embodiment, the high-end field control pin UGATE of the second power supply management chip PU6 is connected to the gate of the second high-end MOS transistor PQ2H1, the low-end field control pin LGATE of the second power supply management chip PU6 is connected to the gate of the second low-end MOS transistor PQ2L1, the drain of the second high-end MOS transistor PQ2H1 is connected to the voltage input terminal VIN, the source of the second high-end MOS transistor PQ2H1 is connected to the drain of the second low-end MOS transistor PQ2L1, one end of the second inductor PL12 and the switch node pin PHASE of the second power supply management chip PU6, and the source of the second low-end MOS transistor PQ2L1 is grounded.

[0022] Specifically, in this embodiment, the bootstrap power supply pin BOOT of the second power supply management chip PU6 is connected to the switch node pin of the second power supply management chip PU6, the source of the second high-end MOS tube PQ2H1, the drain of the second low-end MOS tube PQ2L1 and the second inductor PL12 through the second connection capacitor PC835.

[0023] Specifically, the second power supply management chip PU6 adopts a PWM power supply management chip of model UP1537P.

[0024] Based on the above design, when the auxiliary voltage circuit is working, when the operating voltage required by the central processing unit on the motherboard is a higher voltage, the identification signal of the central processing unit is high, the first gate of the control switch tube is pulled high, the first drain of the control switch tube is connected to the first source, the second gate of the control switch tube is pulled low, the second drain of the control switch tube is disconnected from the second source, the enable pin of the second power supply management chip is pulled high, and the auxiliary voltage circuit output meets the operating voltage required by the central processing unit connected to the motherboard at this time; when the operating voltage required by the central processing unit on the motherboard is a lower voltage, the identification signal of the central processing unit is low, the first gate of the control switch tube is pulled low, the first drain of the control switch tube is disconnected from the first source, the second gate of the control switch tube is pulled high, the second drain of the control switch tube is connected to the second source, the enable pin of the second power supply management chip is pulled low, and the second power supply management chip does not work.

[0025] In summary, the voltage switching control circuit of the present invention is configured by setting a voltage switching switch tube module including a first switch tube and a second switch tube connected to the central processing unit and a voltage dividing resistor group including a first voltage dividing resistor and a second voltage dividing resistor connected to the first switch tube and the second switch tube respectively, and the central processing unit is connected to the first power supply voltage through the third switch tube, and the second voltage dividing resistor connected to the first power supply management chip is electrically connected to the first power supply voltage and the third switch tube through the second switch tube. The central processing unit is connected to the first power supply management chip through the first switch tube via the first voltage dividing resistor, so as to utilize the voltage switching switch tube module to control the corresponding switch tube to be turned on according to the identification signal of the central processing unit on the motherboard received, so that the corresponding voltage dividing resistor and the first feedback resistor are divided, and the voltage converted and output by the first power management chip is adjusted to the working voltage required by the central processing unit, meeting the voltage requirement of the central processing unit, so that the central processing unit can work normally, and realize the voltage switching according to the model of the central processing unit on the motherboard, so that the motherboard can be compatible with central processing units corresponding to different working voltages, thereby improving safety.

[0026] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A voltage switching control circuit, characterized in that: The voltage switching control circuit is installed on a motherboard provided with a central processing unit and is electrically connected to the central processing unit. The voltage switching control circuit includes a first power supply management chip, a voltage switching switch tube module and a voltage dividing resistor group. The voltage dividing resistor group includes a first voltage dividing resistor and a second voltage dividing resistor. The voltage switching switch tube module includes a first switch tube and a second switch tube. The switch node pin of the first power supply management chip is connected to the voltage output terminal, the positive electrode of the thirteenth electrolytic capacitor with the negative electrode grounded, and one end of the first feedback resistor through a first inductor. The other end of the first feedback resistor is connected to the feedback input pin of the first power supply management chip. The feedback input pin of the first power supply management chip is respectively connected to one end of the first voltage dividing resistor and one end of the second voltage dividing resistor. The central processing unit is connected to the other end of the first voltage dividing resistor through the first switch tube. The central processing unit is connected to the first power supply voltage through the third switch tube. The other end of the second voltage dividing resistor is electrically connected between the first power supply voltage and the third switch tube through the second switch tube.

2. The voltage switching control circuit according to claim 1, wherein: The first switching tube, the second switching tube, and the third switching tube are all MOS tubes. The central processing unit is connected to the gates of the third switching tube and the first switching tube, respectively. The sources of the first switching tube, the second switching tube, and the third switching tube are all grounded. The drain of the third switching tube is connected to the first power supply voltage through a first connecting resistor. The gate of the second switching tube is electrically connected between the first connecting resistor and the drain of the third switching tube. The drain of the second switching tube is connected to the feedback input pin of the first power supply management chip and the first feedback resistor through the second voltage dividing resistor. The drain of the first switching tube is connected to the feedback input pin of the first power supply management chip and the first feedback resistor through the first voltage dividing resistor.

3. The voltage switching control circuit according to claim 1, wherein: The high-end field control pin of the first power supply management chip is connected to the gate of the first high-end MOS transistor, the low-end field control pin of the first power supply management chip is connected to the gate of the first low-end MOS transistor, the drain of the first high-end MOS transistor is connected to the voltage input terminal, the source of the first high-end MOS transistor is connected to the drain of the first low-end MOS transistor, one end of the first inductor and the switch node pin of the first power supply management chip, and the source of the first low-end MOS transistor is grounded.

4. The voltage switching control circuit according to claim 3, wherein: The bootstrap power supply pin of the first power supply management chip is connected to the switch node pin of the first power supply management chip, the source of the first high-end MOS tube, the drain of the first low-end MOS tube and the first inductor through a first connection capacitor.

5. The voltage switching control circuit according to claim 1, wherein: The first power supply management chip adopts a PWM power supply management chip with model number UP1537P.

6. The voltage switching control circuit according to claim 1, wherein: The resistance of the first voltage-dividing resistor is smaller than the resistance of the second voltage-dividing resistor.

7. The voltage switching control circuit according to claim 1, wherein: The voltage switching control circuit also includes an auxiliary voltage circuit, which includes a second power supply management chip, a control switch tube and a third voltage divider resistor. The switch node pin of the second power supply management chip is connected to the output end, the positive electrode of the fourteenth electrolytic capacitor with the negative electrode grounded after passing through the second inductor, and one end of the second feedback resistor. The other end of the second feedback resistor is connected to the feedback input pin of the second power supply management chip, and the feedback input pin of the second power supply management chip is grounded after passing through the third voltage divider resistor. The control end of the control switch tube is connected to the central processing unit, the first end of the control switch tube is connected to the second power supply voltage, the second end of the control switch tube is connected to the enable pin of the second power supply management chip, and the enable pin of the second power supply management chip is connected to the third power supply voltage.

8. The voltage switching control circuit according to claim 7, wherein: The control switch tube adopts a MOS tube with model number 2N7002. The first gate of the control switch tube is connected to the central processing unit, the first source and the second source of the control switch tube are both grounded, and the second supply voltage is connected to the first drain and the second gate of the control switch tube respectively after passing through the second connection resistor. The second drain of the control switch tube is connected to the enable pin of the second power supply management chip.

9. The voltage switching control circuit according to claim 7, wherein: The high-end field control pin of the second power supply management chip is connected to the gate of the second high-end MOS tube, the low-end field control pin of the second power supply management chip is connected to the gate of the second low-end MOS tube, the drain of the second high-end MOS tube is connected to the voltage input end, the source of the second high-end MOS tube is connected to the drain of the second low-end MOS tube, one end of the second inductor and the switch node pin of the second power supply management chip, and the source of the second low-end MOS tube is grounded.

10. The voltage switching control circuit according to claim 9, wherein: The bootstrap power supply pin of the second power supply management chip is connected to the switch node pin of the second power supply management chip, the source of the second high-end MOS tube, the drain of the second low-end MOS tube and the second inductor through a second connection capacitor.

Images