Positive and negative voltage generation circuit
By controlling the step-down and negative pressure output modules through a switch control module, the problems of complex circuit structure and low efficiency in the prior art are solved, and efficient output of multiple power supplies and cost savings are achieved.
Patent Information
- Application Number
- CN202423075310.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-12
- Publication Date
- 2025-10-17
- Estimated Expiration
- 2034-12-12
AI Technical Summary
Existing AC-to-DC modules cannot simultaneously meet the voltage requirements of multiple power sources, resulting in complex circuit structures and low efficiency, requiring multiple conversions to output multiple voltages.
A switch control module is used to control the step-down output module and the negative pressure output module, and the simultaneous output of multiple power supplies is achieved through the conduction and discharge of the energy storage branch, reducing the use of circuit components.
It achieves efficient output of multiple power supplies, reduces circuit board size, and saves production costs.
Smart Images
Figure CN223450363U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of electronics, and in particular to a positive and negative voltage generating circuit. BACKGROUND
[0002] At present, some electrical products need positive and negative voltages or different low voltages to realize normal work, for example, a charging pile control guide needs to use a positive and negative 12V power supply output, and a functional module of 12V, 5V and 3V3 needs to be used on some circuit mainboards. However, among the output voltages of the existing AC-DC modules on the market, there are more power outputs from one power supply, and the AC-DC module is difficult to consider the voltage requirements of multiple power supplies at one time, and only one total output power supply is obtained through AC-DC, such as DC12V, and the power requirements of 5V, 3V3 and-12V need to be converted again to obtain the power requirements of 5V, 3V3 and-12V. However, such a power conversion circuit can only output a single positive voltage or negative voltage under the action of a driving switch, and the circuit structure is complex and the efficiency is low. CONTENT OF THE UTILITY MODEL
[0003] The utility model discloses a positive and negative voltage generating circuit, which can control the output of reduced positive voltage and negative voltage through a switch control module, reduces the use of circuit elements, reduces the size of the circuit board, and thus saves production cost and improves the output efficiency of multiple power supplies.
[0004] To achieve the above-mentioned purpose, the present application provides a positive and negative voltage generating circuit, which comprises a step-down output module, a negative voltage output module and a switch control module. The step-down output module comprises a first energy storage branch. The negative voltage output module comprises a second energy storage branch. The switch control module comprises a power input end and a first output end. The power input end is connected with a power supply. The first output end is connected with the input end of the step-down output module and the input end of the negative voltage output module, respectively. When the first output end of the switch control module outputs a high level, the first energy storage branch of the step-down output module is turned on, and the second energy storage branch of the negative voltage output module is turned on. When the first output end of the switch control module outputs a low level, the first energy storage branch of the step-down output module is not turned on, and the second energy storage branch of the negative voltage output module is not turned on.
[0005] The utility model discloses an embodiment of a positive and negative pressure generating circuit has at least the following beneficial effects: through a switch control module and the connection of voltage reduction output module and negative pressure output module, when the first output end of switch control module exports high level, the first energy storage branch of voltage reduction output module is conducted, and the energy storage element in first energy storage branch starts energy storage charging, and the second energy storage branch of negative pressure output module is conducted, and the energy storage element in second energy storage branch starts energy storage charging, when the first output end of switch control module exports low level, the first energy storage branch of voltage reduction output module is not conducted, and the energy storage element in first energy storage branch starts discharging, and the second energy storage branch of negative pressure output module is not conducted, and the energy storage element in second energy storage branch starts discharging, compared with the scheme that needs through multiple switch control modules to control voltage reduction output module and negative pressure output module respectively, the scheme that voltage reduction output module and negative pressure output module share a switch control module can output negative voltage and reduced positive voltage simultaneously, realize multiple power supply output simultaneously, improve the output efficiency of multiple power supply, reduce the use of circuit element, and then reduce the size of circuit board, save production cost.
[0006] In some embodiments, further comprising an input capacitor, a boost capacitor, one end of the input capacitor is connected to the power input end of the switch control module, the other end of the input capacitor is grounded, one end of the boost capacitor is connected to the second output end of the switch control module, and the other end of the boost capacitor is connected to the first output end of the switch control module.
[0007] In some embodiments, the first energy storage branch includes a first inductor and a first capacitor, the first output end of the switch control module is connected to one end of the first inductor, the other end of the first inductor is connected to one end of the first capacitor and the output end of the voltage reduction output module respectively, and the other end of the first capacitor is grounded.
[0008] In some embodiments, the voltage reduction output module further includes a first resistor, a second resistor and a second capacitor, one end of the first resistor and one end of the second capacitor are connected to the other end of the first inductor, the other end of the first resistor, one end of the second resistor and the other end of the second capacitor are connected to the third output end of the switch control module, and the other end of the second resistor is grounded.
[0009] In some embodiments, the second energy storage branch comprises a third capacitor and a first diode, the negative voltage output module further comprises a second diode and a fourth capacitor, the first output end of the switch control module is connected to one end of the third capacitor, the other end of the third capacitor is connected to the positive electrode of the first diode and the negative electrode of the second diode respectively, the positive electrode of the second diode is connected to one end of the fourth capacitor and the output end of the negative voltage output module respectively, and the negative electrode of the first diode and the other end of the fourth capacitor are both grounded.
[0010] In some embodiments, the switch control module further comprises a first switch assembly, a second switch assembly and a first control module, the power input end of the switch control module is connected to the power input end of the first switch assembly, the first output end of the switch control module is connected to the first output end of the first switch assembly and the output end of the second switch assembly respectively, the first input end of the first switch assembly is connected to the first output end of the first control module, and the input end of the second switch assembly is connected to the second output end of the first control module.
[0011] In some embodiments, the first switch assembly comprises a first NMOS tube and a first PMOS tube, the power input end of the switch control module is connected to the drain of the first PMOS tube, the first output end of the switch control module is connected to the source of the first PMOS tube, the gate of the first NMOS tube is connected to the first output end of the first control module, the source of the first NMOS tube is grounded, and the drain of the first NMOS tube is connected to the gate of the first PMOS tube.
[0012] In some embodiments, the switch control module further comprises a third switch assembly, a fourth switch assembly, a second control module and a half-bridge drive module, the power input end of the switch control module is connected to the power input end of the third switch assembly, the first output end of the switch control module is connected to the first output end of the third switch assembly, the output end of the fourth switch assembly and the half-bridge drive module respectively, the first input end of the third switch assembly, the input end of the fourth switch assembly and the second control module are all connected to the half-bridge drive module.
[0013] In some embodiments, the third switch assembly comprises a second NMOS tube, the power input end of the switch control module is connected to the drain of the second NMOS tube, the first output end of the switch control module is connected to the source of the second NMOS tube and the half-bridge drive module respectively, and the gate of the second NMOS tube is connected to the half-bridge drive module.
[0014] In some embodiments, the second switch assembly comprises a third NMOS tube, a first output end of the switch control module is connected with a drain of the third NMOS tube, a gate of the third NMOS tube is connected with a second output end of the first control module, and a source of the third NMOS tube is grounded. BRIEF DESCRIPTION OF DRAWINGS
[0015] The accompanying drawings are used to provide a further understanding of the technical scheme of the present application, and constitute a part of the description, and are used together with the embodiments of the present application to explain the technical scheme of the present application, and do not constitute a limitation on the technical scheme of the present application.
[0016] The present application is further described below in combination with the drawings and embodiments;
[0017] Figure 1 is a structural block diagram of a positive and negative pressure generating circuit provided by an embodiment of the present application;
[0018] Figure 2 is a principle diagram of a positive and negative pressure generating circuit provided by an embodiment of the present application;
[0019] Figure 3 is a connection principle diagram of an internal integrated switch in a switch control module provided by an embodiment of the present application;
[0020] Figure 4 is a principle diagram of a positive and negative pressure generating circuit containing a multi-path negative pressure output module provided by an embodiment of the present application;
[0021] Figure 5 is a principle diagram of another positive and negative pressure generating circuit provided by an embodiment of the present application;
[0022] Figure 6 is a principle diagram of still another positive and negative pressure generating circuit provided by an embodiment of the present application. DETAILED DESCRIPTION
[0023] This part will describe the specific embodiments of the present application in detail, and the preferred embodiments of the present application are shown in the drawings, and the role of the drawings is to supplement the description of the text part with figures, so that people can intuitively and visually understand each technical feature and the overall technical scheme of the present application, but it cannot be understood as a limitation on the protection scope of the present application.
[0024] In the description of the present application, if the first and the second are described for the purpose of distinguishing technical features, it cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the sequence of indicated technical features.
[0025] In the description of the utility model, unless otherwise explicitly limited, the words such as setting, installing, connecting should be understood broadly, and the specific meaning of the above words in the utility model can be determined by the person skilled in the art in combination with the specific content of the technical scheme.
[0026] The utility model embodiment provides a kind of positive and negative pressure generating circuit, and the positive voltage and negative pressure after output reduction can be controlled by a switch control module, reduce the use of circuit element, reduce the size of circuit board, to save production cost and improve the output efficiency of multiple power supply in turn.
[0027] The utility model embodiment is further described below with reference to the drawings.
[0028] Refer to Figure 1 The utility model provides a kind of positive and negative pressure generating circuit, comprising: step-down output module 2000, negative pressure output module 3000 and switch control module 1000, step-down output module 2000 includes first energy storage branch 2100;Negative pressure output module 3000 includes second energy storage branch 3100;Switch control module 1000 includes power input terminal VIN, first output end Uo, power input terminal VIN is connected with power supply, and first output end Uo is connected with the input terminal of step-down output module 2000 and the input terminal of negative pressure output module 3000 respectively;Wherein, when the first output end Uo of switch control module 1000 exports high level, the first energy storage branch 2100 of step-down output module 2000 is conducted, and the second energy storage branch 3100 of negative pressure output module 3000 is conducted;When the first output end Uo of switch control module 1000 exports low level, the first energy storage branch 2100 of step-down output module 2000 is not conducted, and the second energy storage branch 3100 of negative pressure output module 3000 is not conducted.
[0029] According to the positive and negative pressure generating circuit, the switch control module 1000 is connected with the voltage reduction output module 2000 and the negative pressure output module 3000, when the first output end Uo of the switch control module 1000 outputs a high level, the first energy storage branch 2100 of the voltage reduction output module 2000 is turned on, the energy storage element in the first energy storage branch 2100 starts to store energy and charge, the second energy storage branch 3100 of the negative pressure output module 3000 is turned on, and the energy storage element in the second energy storage branch 3100 starts to store energy and charge; when the first output end Uo of the switch control module 1000 outputs a low level, the first energy storage branch 2100 of the voltage reduction output module 2000 is not turned on, the energy storage element in the first energy storage branch 2100 starts to discharge, the second energy storage branch 3100 of the negative pressure output module 3000 is not turned on, and the energy storage element in the second energy storage branch 3100 starts to discharge; compared with the scheme that the voltage reduction output module 2000 and the negative pressure output module 3000 are respectively controlled by a plurality of switch control modules 1000, the scheme that the voltage reduction output module 2000 and the negative pressure output module 3000 share one switch control module 1000 can simultaneously output negative voltage and reduced positive voltage, realizes simultaneous output of multiple power supplies, improves the output efficiency of the multiple power supplies, reduces the use of circuit elements, and further reduces the size of the circuit board and saves production cost.
[0030] In some embodiments, referring to Figure 2 The switch control module 1000 is connected with the voltage reduction output module 2000 and the negative pressure output module 3000, when the first output end Uo of the switch control module 1000 outputs a high level, the first energy storage branch 2100 of the voltage reduction output module 2000 is turned on, the energy storage element in the first energy storage branch 2100 starts to store energy and charge, the second energy storage branch 3100 of the negative pressure output module 3000 is turned on, and the energy storage element in the second energy storage branch 3100 starts to store energy and charge; when the first output end Uo of the switch control module 1000 outputs a low level, the first energy storage branch 2100 of the voltage reduction output module 2000 is not turned on, the energy storage element in the first energy storage branch 2100 starts to discharge, the second energy storage branch 3100 of the negative pressure output module 3000 is not turned on, and the energy storage element in the second energy storage branch 3100 starts to discharge; compared with the scheme that the voltage reduction output module 2000 and the negative pressure output module 3000 are respectively controlled by a plurality of switch control modules 1000, the scheme that the voltage reduction output module 2000 and the negative pressure output module 3000 share one switch control module 1000 can simultaneously output negative voltage and reduced positive voltage, realizes simultaneous output of multiple power supplies, improves the output efficiency of the multiple power supplies, reduces the use of circuit elements, and further reduces the size of the circuit board and saves production cost.
[0031] Preferably, the switch control module 1000 is a BUCK chip RY3834, and the type of the switch control module 1000 is not limited here.
[0032] It can be understood that when the switch control module 1000 is a BUCK chip with an integrated drive manager and switch component, the switch control module 1000 can automatically control the output voltage without an additional controller and drive circuit, further reducing the use of elements and the size of the circuit board.
[0033] Referring to Figure 2In some embodiments, the first energy storage branch 2100 includes a first inductor L1 and a first capacitor COUT, one end of the first inductor L1 is connected to the first output Uo of the switch control module 1000, the other end of the first inductor L1 is connected to one end of the first capacitor COUT and the output VOUT+ of the step-down output module 2000 respectively, and the other end of the first capacitor COUT is grounded.
[0034] It should be noted that when the switch control module 1000 is a BUCK chip internally integrated with a drive manager and a switch component, the switch component includes a first switch K1 and a second switch K2, the connection of the first switch K1 and the second switch K2 is as shown in Figure 3 , and the first switch K1 and the second switch K2 are not turned on at the same time, one end of the first inductor L1 is connected to the first output Uo of the switch control module 1000, one end of the boost capacitor C1 is connected to the second output BS of the switch control module 1000, and the other end of the second capacitor CF is connected to the third output FB of the switch control module 1000.
[0035] Further, when the first output Uo of the switch control module 1000 outputs a high level, the internal first switch K1 is turned on, the power supply flows through the first energy storage branch 2100 in the step-down output module 2000 through the switch control module 1000, the first energy storage branch 2100 is turned on, and the first inductor L1 and the first capacitor COUT store energy; when the first output Uo of the switch control module 1000 outputs a low level, the internal second switch K2 is turned on, the power supply cannot flow through the first energy storage branch 2100 in the step-down output module 2000 through the switch control module 1000, the first energy storage branch 2100 is not turned on, the first inductor L1, the second switch K2 and the first capacitor COUT form a loop, the first inductor L1 keeps charging the first capacitor COUT through the second switch K2 inside the switch control module 1000, the first capacitor COUT discharges externally, and the output VOUT+ of the step-down module outputs a reduced positive voltage.
[0036] In some embodiments, referring to Figure 2 , the step-down output module 2000 further includes a first resistor R1, a second resistor R2 and a second capacitor CF, one end of the first resistor R1 and one end of the second capacitor CF are connected to the other end of the first inductor L1, the other end of the first resistor R1, one end of the second resistor R2 and the other end of the second capacitor CF are connected to the third output of the switch control module 1000, and the other end of the second resistor R2 is grounded.
[0037] It should be noted that when the switch control module 1000 is a BUCK chip internally integrated with a drive manager and a switch assembly, the other end of the first resistor R1 and one end of the second resistor R2 are connected to the third output end of the switch control module 1000, that is, the FB pin of the BUCK chip. The first resistor R1 and the second resistor R2 feed back the output voltage of the voltage reduction module to the FB pin of the BUCK chip after voltage division, wherein the FB pin has a clamping effect, and the BUCK chip adjusts the output high level or low level of the SW pin by adjusting the on-off of the internal first switch K1 and the second switch K2.
[0038] In some embodiments, the second energy storage branch 3100 includes a third capacitor C2 and a first diode D1, and the negative voltage output module 3000 further includes a second diode D2 and a fourth capacitor COUT1. One end of the third capacitor C2 is connected to the first output end Uo of the switch control module 1000. The other end of the third capacitor C2 is connected to the anode of the first diode D1 and the cathode of the second diode D2, respectively. The anode of the second diode D2 is connected to one end of the fourth capacitor COUT1 and the output end of the negative voltage output module 3000, respectively. The cathode of the first diode and the other end of the fourth capacitor COUT1 are both grounded.
[0039] It should be noted that when the switch control module 1000 is a BUCK chip internally integrated with a drive manager and a switch assembly, the first output end of the switch control module 1000, that is, the SW pin of the BUCK chip, is connected to one end of the third capacitor C2. Further, when the SW pin of the BUCK chip outputs a high level, the internal first switch is turned on, and the current of the power supply flows through the second energy storage branch 3100 in the negative voltage output module 3000 through the switch control module 1000. The current flows through the third capacitor C2 and the first diode D1, and the third capacitor C2 stores energy. When the SW pin of the BUCK chip outputs a low level, the internal second switch K2 is turned on, and the current of the power supply cannot flow through the second energy storage branch 3100 in the negative voltage output module 3000 through the switch control module 1000. The second energy storage branch 3100 is not conductive, and the third capacitor C2, the second switch K2, the fourth capacitor COUT1, and the second diode D2 form a loop. The third capacitor C2 discharges through the fourth capacitor COUT1 and the second diode D2, and the negative voltage output end VOUT1 outputs a negative voltage.
[0040] It can be understood that the third capacitor C2 plays a role of energy transfer, transferring the energy output by the first switch control module 1000 to the fourth capacitor COUT1.
[0041] In some embodiments, referring to Figure 4The circuit comprises a plurality of negative voltage output modules 3000, and the first output end Uo of the switch control module 1000 is connected with the input ends of the plurality of negative voltage output modules 3000.
[0042] It should be noted that different negative voltages can be output by adjusting the value of the capacitor in the negative voltage output module 3000 to meet the different negative voltage requirements of different electrical components in the circuit.
[0043] In some embodiments, referring to Figure 5 The switch control module 1000 further comprises a first switch assembly 1110, a second switch assembly 1120 and a first control module 1130, the power input end VIN of the switch control module 1000 is connected with the power input end of the first switch assembly 1110, the first output end Uo of the switch control module 1000 is connected with the first output end of the first switch assembly 1110 and the output end of the second switch assembly 1120, the first input end of the first switch assembly 1110 is connected with the first output end of the first control module 1130, and the input end of the second switch assembly 1120 is connected with the second output end of the first control module 1130.
[0044] It can be understood that the switch control module 1000 is composed of the first switch assembly 1110, the second switch assembly 1120 and the first control module 1130, and the switch control module 1000 is carried by separate devices, so that when the switch control module 1000 is damaged, only the damaged device needs to be replaced, instead of the entire switch control module 1000, thereby saving production cost.
[0045] It should be noted that when the first switch assembly 1110 is turned on, the second switch assembly 1120 is not turned on, and the first output end of the first control module 1130 can output a driving signal S1 and the second output end can output a driving signal S2 to control the first switch assembly 1110 and the second switch assembly 1120 to stagger the turning-on time, thereby ensuring that the voltage reduction output module 2000 and the negative voltage output module 3000 can normally store energy and discharge.
[0046] In some embodiments, the first switch assembly 1110 comprises a first NMOS tube Q2 and a first PMOS tube Q1, the power input end VIN of the switch control module 1000 is connected with the drain of the first PMOS tube Q1, the first output end Uo of the switch control module 1000 is connected with the source of the first PMOS tube Q1, the gate of the first NMOS tube Q2 is connected with the first output end of the first control module 1130, the source of the first NMOS tube Q2 is grounded, and the drain of the first NMOS tube Q2 is connected with the gate of the first PMOS tube Q1.
[0047] It should be noted that the first output end of the first control module 1130 outputs the driving signal S1 for controlling the first PMOS Q1 in the first switch assembly 1110 and the second switch assembly 1120. In order to make the first PMOS Q1 effectively and quickly turn off when it is turned off, the first NMOS Q2 is added to optimize the driving of the first PMOS Q1.
[0048] Further, under the condition that the second switch assembly 1120 is not turned on, when the first output end of the first control module 1130 outputs the driving signal S1 as high level, the first NMOS Q2 is turned on, the gate voltage of the first PMOS Q1 is low level, the first PMOS Q1 is turned on, the power supply supplies power to the negative voltage output module 3000 and the step-down output module 2000 through the first PMOS Q1, and the first energy storage branch 2100 and the second energy storage branch 3100 are turned on; under the condition that the second switch assembly 1120 is turned on, when the first output end of the first control module 1130 outputs the driving signal S1 as low level, the first NMOS Q2 is turned off, the gate voltage of the first PMOS Q1 is high level, the first PMOS Q1 is turned off, the power supply cannot pass through the first PMOS Q1, the first energy storage branch 2100 and the second energy storage branch 3100 are not turned on, the energy storage element in the first energy storage branch 2100 is discharged and outputs the reduced positive voltage at the output end, and the energy storage element in the second energy storage branch 3100 is discharged and outputs the negative voltage at the output end.
[0049] In some embodiments, the second switch assembly 1120 includes a third NMOS Q3, the first output end Uo of the switch control module 1000 is connected with the drain of the third NMOS Q3, the gate of the third NMOS Q3 is connected with the second output end of the first control module 1130, and the source of the third NMOS Q3 is grounded.
[0050] It can be understood that when the second output end of the first control module 1130 outputs the driving signal S2 as high level, the third NMOS Q3 is turned on; when the second output end of the first control module 1130 outputs the driving signal S2 as low level, the third NMOS Q3 is turned off.
[0051] In some embodiments, the first switch assembly 1110 includes a first NMOS tube Q2 and a first PMOS tube Q1, a power input end VIN of the switch control module 1000 is connected with a drain of the first PMOS tube Q1, a first output end Uo of the switch control module 1000 is connected with a source of the first PMOS tube Q1, a gate of the first NMOS tube Q2 is connected with a first output end of the first control module 1130 through a resistor element, a source of the first NMOS tube Q2 is grounded, a drain of the first NMOS tube Q2 is connected with a gate of the first PMOS tube Q1 through a resistor element; the second switch assembly 1120 includes a third NMOS tube Q3, a third resistor R3 and a fourth resistor R4, the first output end Uo of the switch control module 1000 is connected with a drain of the third NMOS tube Q3, a gate of the third NMOS tube Q3 is connected with one end of the third resistor R3 and one end of the fourth resistor R4 respectively, the other end of the third resistor R3 is connected with a second output end of the first control module 1130, a source of the third NMOS tube Q3 and the other end of the fourth resistor R4 are grounded; the first output end Uo of the switch control module 1000 is connected with one end of a first inductor L1, the other end of the first inductor L1 is connected with one end of a first capacitor COUT and an output end VOUT+ of the step-down output module 2000 respectively, the other end of the first capacitor COUT is grounded; the first output end Uo of the switch control module 1000 is connected with one end of a third capacitor C2, the other end of the third capacitor C2 is connected with a positive electrode of a first diode D1 and a negative electrode of a second diode D2 respectively, the positive electrode of the second diode D2 is connected with one end of a fourth capacitor COUT1 and an output end VOUT1 of the negative voltage output module 3000 respectively, the negative electrode of the first diode D1 and the other end of the fourth capacitor COUT1 are grounded.
[0052] It should be noted that when the first output end of the first control module 1130 outputs the driving signal S1 as high level and the second output end outputs the driving signal S2 as low level, the first NMOS tube Q2 and the first PMOS tube Q1 are both turned on, the third NMOS tube Q3 is turned off, the current of the power supply can pass through the first PMOS tube Q1, the first output end Uo of the switch control module 1000 outputs high level, the current charges the first inductor L1 and the first capacitor COUT through the first energy storage branch 2100, and at the same time, the current also charges the third capacitor C2 through the second energy storage branch 3100; when the first output end of the first control module 1130 outputs the driving signal S1 as low level and the second output end outputs the driving signal S2 as high level, the first NMOS tube Q2 and the first PMOS tube Q1 are both turned off, the third NMOS tube Q3 is turned on, the power supply stops supplying power, the first output end Uo of the switch control module 1000 outputs low level, the first inductor L1, the third NMOS tube Q3 and the first capacitor COUT form a step-down circuit, the first inductor L1 keeps charging the first capacitor COUT, the first capacitor COUT discharges to the outside, and a negative voltage is output at the output end VOUT+ of the step-down output module 2000. In addition, the third capacitor C2, the third NMOS tube Q3, the fourth capacitor COUT1 and the second diode D2 form a negative voltage circuit, the third capacitor C2 charges the fourth capacitor COUT1, and the fourth capacitor COUT1 discharges to the outside, and a negative voltage is output at the output end of the negative voltage output module 3000.
[0053] In some embodiments, with reference to Figure 6 , the switch control module 1000 further comprises a third switch assembly 1210, a fourth switch assembly 1220, a second control module 1230 and a half-bridge drive module 1240, the power input end VIN of the switch control module 1000 is connected with the power input end of the third switch assembly 1210, the first output end Uo of the switch control module 1000 is connected with the first output end of the third switch assembly 1210, the output end of the fourth switch assembly 1220 and the half-bridge drive module 1240 respectively, and the first input end of the third switch assembly 1210, the input end of the fourth switch assembly 1220 and the second control module 1230 are all connected with the half-bridge drive module 1240.
[0054] It can be understood that the switch control module 1000 is composed of the third switch assembly 1210, the fourth switch assembly 1220, the second control module 1230 and the half-bridge drive module 1240, and separate devices are used to carry the switch control module 1000. When the switch control module 1000 is damaged, only the damaged device needs to be replaced, instead of replacing the entire switch control module 1000, thereby saving production cost.
[0055] It should be noted that when the third switch assembly 1210 is turned on, the fourth switch assembly 1220 is not turned on, and the half-bridge drive module 1240 can be controlled by the second control module 1230 to control the third switch assembly 1210 and the fourth switch assembly 1220 to stagger the turn-on time, so as to ensure that the step-down output module 2000 and the negative voltage output module 3000 can normally store energy and charge and discharge.
[0056] In some embodiments, the third switch assembly 1210 includes a second NMOS tube Q4, the power input end VIN of the switch control module 1000 is connected with the drain of the second NMOS tube Q4, the first output end Uo of the switch control module 1000 is connected with the source of the second NMOS tube Q4 and the half-bridge drive module 1240 respectively, and the gate of the second NMOS tube Q4 is connected with the half-bridge drive module 1240.
[0057] It can be understood that the half-bridge drive module 1240 can provide sufficient gate drive voltage and current for the second NMOS tube Q4, so as to ensure that the second NMOS tube Q4 can normally turn on and turn off, the pin Ho of the half-bridge drive module 1240 is connected with the gate of the second NMOS tube Q4 through a resistor, and the pin VS of the half-bridge drive module 1240 is connected with the source of the second NMOS tube Q4.
[0058] It can be understood that the half-bridge drive module 1240 internally integrates a bootstrap circuit, taking the level of the source of the second NMOS tube Q4 as a reference level 0V, under the premise that the fourth switch assembly 1220 is turned off, when the level of the drive signal output by the pin Ho of the half-bridge drive module 1240 is higher than the level of the source of the second NMOS tube Q4, the second NMOS tube Q4 is turned on, and the current of the power supply is supplied to the first energy storage branch 2100 in the step-down output module 2000 and the second energy storage branch 3100 in the negative voltage output module 3000 through the second NMOS tube Q4.
[0059] In some embodiments, the fourth switch assembly 1220 includes a fourth NMOS tube Q5, a fifth resistor R5 and a sixth resistor R6, the first output end Uo of the switch control module 1000 is connected with the drain of the fourth NMOS tube Q5, the gate of the fourth NMOS tube Q5 is connected with one end of the fifth resistor R5 and one end of the sixth resistor R6, the other end of the fifth resistor R5 is connected with the half-bridge drive module 1240, and the source of the third NMOS tube Q3 and the other end of the sixth resistor R6 are grounded.
[0060] It can be understood that the pin LO of the half-bridge drive module 1240 is connected with the other end of the fifth resistor R5, and under the premise that the second NMOS tube Q4 is off, when the pin LO of the half-bridge drive module 1240 outputs a high level, the fourth NMOS tube Q5 is turned on, the output end VOUT1 of the negative voltage output module 3000 outputs a negative voltage, the output end VOUT+ of the step-down voltage output module 2000 outputs a reduced positive voltage, at the same time, the pin VB of the half-bridge drive module 1240 is connected with one end of the bootstrap capacitor C3, the other end of the bootstrap capacitor C3 is connected with the source of the second NMOS tube Q4, the bootstrap capacitor C3 is charged by the circuit when the fourth NMOS tube Q5 is turned on, and the reference level of the bootstrap capacitor C3 is 0V; when the fourth NMOS tube Q5 is off, the level of the source of the second NMOS tube Q4 is the reference level 0V, the level of the source of the second NMOS tube Q4 is taken as a reference, so that when the second NMOS tube is driven, the level of the driving signal can be stably higher than the level of the source of the second NMOS tube Q4.
[0061] The above describes the embodiments of the utility model in detail in combination with the drawings, but the utility model is not limited to the above-mentioned embodiments, and various changes can be made within the knowledge range possessed by the ordinary skilled in the art without departing from the purpose of the utility model.
Claims
1. A positive and negative voltage generating circuit, characterized in that: include: A step-down output module, the step-down output module comprising a first energy storage branch; A negative pressure output module, the negative pressure output module comprising a second energy storage branch; A switch control module, the switch control module comprising a power input terminal and a first output terminal, the power input terminal being connected to a power supply, the first output terminal being connected to an input terminal of the step-down output module and an input terminal of the negative pressure output module respectively; Among them, when the first output end of the switch control module outputs a high level, the first energy storage branch of the step-down output module is turned on, and the second energy storage branch of the negative pressure output module is turned on; when the first output end of the switch control module outputs a low level, the first energy storage branch of the step-down output module is not turned on, and the second energy storage branch of the negative pressure output module is not turned on.
2. The positive and negative voltage generating circuit according to claim 1, characterized in that: It also includes an input capacitor and a lifting capacitor, one end of the input capacitor is connected to the power input end of the switch control module, the other end of the input capacitor is grounded, one end of the lifting capacitor is connected to the second output end of the switch control module, and the other end of the lifting capacitor is connected to the first output end of the switch control module.
3. The positive and negative voltage generating circuit according to claim 1, characterized in that: The first energy storage branch includes a first inductor and a first capacitor. The first output end of the switch control module is connected to one end of the first inductor, the other end of the first inductor is respectively connected to one end of the first capacitor and the output end of the step-down output module, and the other end of the first capacitor is grounded.
4. The positive and negative voltage generating circuit according to claim 3, characterized in that: The step-down output module further includes a first resistor, a second resistor, and a second capacitor, one end of the first resistor and one end of the second capacitor are both connected to the other end of the first inductor, the other end of the first resistor, one end of the second resistor, and the other end of the second capacitor are all connected to the third output end of the switch control module, and the other end of the second resistor is grounded.
5. The positive and negative voltage generating circuit according to claim 1, characterized in that: The second energy storage branch includes a third capacitor and a first diode, and the negative voltage output module also includes a second diode and a fourth capacitor. The first output end of the switch control module is connected to one end of the third capacitor, and the other end of the third capacitor is respectively connected to the positive electrode of the first diode and the negative electrode of the second diode. The positive electrode of the second diode is respectively connected to one end of the fourth capacitor and the output end of the negative voltage output module, and the negative electrode of the first diode and the other end of the fourth capacitor are both grounded.
6. The positive and negative voltage generating circuit according to claim 1, characterized in that: The switch control module also includes a first switch component, a second switch component and a first control module. The power input end of the switch control module is connected to the power input end of the first switch component. The first output end of the switch control module is respectively connected to the first output end of the first switch component and the output end of the second switch component. The first input end of the first switch component is connected to the first output end of the first control module, and the input end of the second switch component is connected to the second output end of the first control module.
7. The positive and negative voltage generating circuit according to claim 6, characterized in that: The first switch component includes a first NMOS transistor and a first PMOS transistor. The power input end of the switch control module is connected to the drain of the first PMOS transistor, the first output end of the switch control module is connected to the source of the first PMOS transistor, the gate of the first NMOS transistor is connected to the first output end of the first control module, the source of the first NMOS transistor is grounded, and the drain of the first NMOS transistor is connected to the gate of the first PMOS transistor.
8. The positive and negative voltage generating circuit according to claim 1, characterized in that: The switch control module also includes a third switch component, a fourth switch component, a second control module and a half-bridge driver module. The power input end of the switch control module is connected to the power input end of the third switch component. The first output end of the switch control module is respectively connected to the first output end of the third switch component, the output end of the fourth switch component and the half-bridge driver module. The first input end of the third switch component, the input end of the fourth switch component and the second control module are all connected to the half-bridge driver module.
9. The positive and negative voltage generating circuit according to claim 8, characterized in that: The third switch component includes a second NMOS transistor, the power input end of the switch control module is connected to the drain of the second NMOS transistor, the first output end of the switch control module is respectively connected to the source of the second NMOS transistor and the half-bridge drive module, and the gate of the second NMOS transistor is connected to the half-bridge drive module.
10. The positive and negative voltage generating circuit according to claim 6, characterized in that: The second switch component includes a third NMOS transistor, the first output end of the switch control module is connected to the drain of the third NMOS transistor, the gate of the third NMOS transistor is connected to the second output end of the first control module, and the source of the third NMOS transistor is grounded.