Driving circuit and LED circuit

Abstract

The utility model provides a driving circuit and an LED circuit, and relates to the technical field of driving circuits. In the driving circuit, a first output end of a voltage comparison circuit is connected with a booster circuit, and a second output end of the voltage comparison circuit is connected with a step-down circuit; the output end of the booster circuit and the output end of the step-down circuit are connected with the same load to be powered; a voltage dividing end and an input end of the voltage dividing circuit are respectively connected with the voltage comparison circuit, and the voltage dividing circuit is used for outputting divided voltage of external voltage of the input end through the voltage dividing end; the voltage comparison circuit is used for transmitting the external voltage of the input end to the boost circuit through the first output end when the voltage of the divided voltage is lower than the reference voltage, and transmitting the external voltage of the input end to the buck circuit through the second output end when the voltage of the divided voltage is larger than or equal to the reference voltage. According to the embodiment of the invention, the interference of external voltage change on the load can be reduced, the normal work of equipment is effectively ensured, and the safety and stability of the equipment are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of driving circuit, in particular, the present application relates to a driving circuit and LED circuit. BACKGROUND

[0002] With the development of science and technology and life, more and more devices begin to use electric power driving. Although this electric power driving mode can effectively reduce the environmental pollution generated by the device, in the process of using the device, the load in the device is often powered by connecting multiple devices in the circuit or using a battery power supply mode. This power supply mode is prone to cause the voltage received by the load to change due to the opening or working state change of other devices or the state change (such as power or use time, use frequency change) of the battery itself, which affects the normal work of the device, and even endangers the safety of the device. CONTENT OF THE UTILITY MODEL

[0003] The embodiment of the present application provides a driving circuit and LED circuit, which can solve the problem that the voltage received by the load is unstable, affects the normal work of the device, and even endangers the safety of the device.

[0004] In order to achieve the purpose, the embodiment of the present application provides the following several schemes.

[0005] According to one aspect of the embodiment of the present application, a driving circuit is provided, comprising a voltage dividing circuit, a voltage comparison circuit, a voltage boosting circuit and a voltage reducing circuit, the first output end of the voltage comparison circuit is connected with the voltage boosting circuit, and the second output end of the voltage comparison circuit is connected with the voltage reducing circuit;

[0006] The output end of the voltage boosting circuit and the output end of the voltage reducing circuit are connected with the same load to be powered;

[0007] The voltage dividing end and the input end of the voltage dividing circuit are connected with the voltage comparison circuit respectively, and the voltage dividing circuit is used for outputting the voltage division of the external voltage of the input end through the voltage dividing end;

[0008] The voltage comparison circuit is used for voltage comparison of the reference voltage and the voltage division, and when the voltage of the voltage division is lower than the reference voltage, the external voltage of the input end is transmitted to the voltage boosting circuit through the first output end, and when the voltage of the voltage division is greater than or equal to the reference voltage, the external voltage of the input end is transmitted to the voltage reducing circuit through the second output end.

[0009] In one possible implementation, the voltage dividing circuit comprises a thirteenth resistor and a twenty-fifth resistor, the second end of the twenty-fifth resistor is grounded, the first end of the twenty-fifth resistor is connected with the voltage comparison circuit and the second end of the thirteenth resistor, and the first end of the thirteenth resistor is connected with the external voltage.

[0010] The voltage comparison circuit comprises a judging circuit provided with an operational amplifier, the non-inverting input terminal of the operational amplifier is connected to the reference voltage, and the inverting input terminal is connected to the second terminal of the thirteenth resistor.

[0011] In a possible implementation, the voltage comparison circuit further comprises a first switching circuit provided with a third transistor, a first relay, and a fourth diode, the base of the third transistor is connected to the output terminal of the operational amplifier, the emitter of the third transistor is grounded, the collector of the third transistor is connected to the first terminal of the first relay and the anode of the fourth diode, the cathode of the fourth diode is connected to the fifth terminal of the first relay, the fifth terminal of the first relay is connected to the working voltage, the fourth terminal of the first relay is connected to the external voltage, the second terminal of the first relay is connected to the second output terminal of the voltage comparison circuit, and the third terminal of the first relay is connected to the first output terminal of the voltage comparison circuit.

[0012] In a possible implementation, the voltage comparison circuit further comprises a second switching circuit provided with a fourth transistor, a sixth diode, and a second relay, the input terminal of the fourth transistor is connected to the output terminal of the operational amplifier, the emitter of the fourth transistor is grounded, the collector of the fourth transistor is connected to the anode of the sixth diode and the first terminal of the second relay, the cathode of the sixth diode is connected to the fifth terminal of the second relay, the fifth terminal of the second relay is connected to the working voltage, the fourth terminal of the second relay is grounded, the second terminal of the second relay is connected to the voltage reduction circuit, and the third terminal of the second relay is connected to the voltage increase circuit.

[0013] In a possible implementation, the power supply circuit further comprises a direct current converter, a thirty-sixth resistor, and a thirty-seventh resistor, the input terminal of the direct current converter is connected to the external voltage, the output terminal of the direct current converter is connected to the second terminal of the thirty-seventh resistor, and the working voltage is outputted;

[0014] The first terminal of the thirty-seventh resistor is connected to the feedback terminal of the direct current converter and the second terminal of the thirty-sixth resistor, and the first terminal of the thirty-sixth resistor is grounded.

[0015] In a possible implementation, the power supply circuit further comprises a voltage stabilizing chip, a fifty-ninth capacitor, and a sixtieth capacitor, the input terminal of the voltage stabilizing chip is connected to the second terminal of the thirty-seventh resistor, the ground terminal of the voltage stabilizing chip is grounded, the output terminal of the voltage stabilizing chip is connected to the first terminal of the fifty-ninth capacitor and the first terminal of the sixtieth capacitor, and the second terminal of the fifty-ninth capacitor and the second terminal of the sixtieth capacitor are grounded.

[0016] In a possible implementation, the power supply circuit further includes a third inductor, a fifth diode, a forty-first capacitor, a thirty-seventh capacitor, a thirty-eighth capacitor, and an eleventh capacitor, a first end of the third inductor is connected with an output end of the direct current converter and a cathode of the fifth diode, an anode of the fifth diode is grounded, and is connected with a second end of the forty-first capacitor, a second end of the thirty-seventh capacitor, a second end of the thirty-eighth capacitor, and a second end of the eleventh capacitor, and a first end of the third inductor is connected with a second end of the thirty-seventh resistor, a first end of the forty-first capacitor, a first end of the thirty-seventh capacitor, a first end of the thirty-eighth capacitor, and a first end of the eleventh capacitor.

[0017] In a possible implementation, the boost circuit includes a first constant current driver, a second resistor, a fourth capacitor, and a seventh capacitor, a first end of the second resistor is connected with a positive pole of the first output end and a first end of the load, a second end of the second resistor is connected with a first end of the fourth capacitor and an enable end of the first constant current driver, a second end of the fourth capacitor is connected with a negative pole of the first output end, a second end of the seventh capacitor, and a ground pin of the first constant current driver, a first end of the seventh capacitor is connected with a frequency compensation pin of the first constant current driver, and an output pin of the first constant current driver is connected with a second end of the load.

[0018] In a possible implementation, the boost circuit includes a first constant current driver, a second resistor, a fourth capacitor, and a seventh capacitor, a first end of the second resistor is connected with a positive pole of the first output end and a first end of the load, a second end of the second resistor is connected with a first end of the fourth capacitor and an enable end of the first constant current driver, a second end of the fourth capacitor is connected with a negative pole of the first output end, a second end of the seventh capacitor, and a ground pin of the first constant current driver, a first end of the seventh capacitor is connected with a frequency compensation pin of the first constant current driver, and an output pin of the first constant current driver is connected with a second end of the load.

[0019] According to an aspect of an embodiment of the present application, an LED circuit is provided, which includes the driving circuit as described above.

[0020] The technical scheme provided by the embodiments of the present application has the beneficial effects that:

[0021] The first output end of the voltage comparison circuit in the driving circuit provided by the present application is connected with the voltage boosting circuit, and the second output end of the voltage comparison circuit is connected with the voltage reducing circuit; the output end of the voltage boosting circuit and the output end of the voltage reducing circuit are both connected with at least one load to be powered, and the driving voltages of the loads are the same; the voltage dividing end and the input end of the voltage dividing circuit are respectively connected with the voltage comparison circuit, and the voltage dividing circuit is used for outputting the voltage division of the external voltage at the input end through the voltage dividing end; the voltage comparison circuit is used for voltage comparison on the reference voltage and the voltage division, and when the voltage of the voltage division is lower than the reference voltage, the external voltage at the input end is transmitted to the voltage boosting circuit through the first output end, and when the voltage of the voltage division is greater than or equal to the reference voltage, the external voltage at the input end is transmitted to the voltage reducing circuit through the second output end. The embodiments of the present application can control the voltage boosting circuit to perform the voltage boosting operation on the external voltage or utilize the voltage reducing circuit to perform the voltage reducing operation on the external voltage according to the change of the external voltage, thereby reducing the interference of the change of the external voltage on the load, effectively ensuring the normal work of the equipment, and improving the safety and stability of the equipment. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical scheme in the embodiments of the present application, the drawings needed to be used in the description of the embodiments of the present application will be briefly introduced.

[0023] Figure 1 The structural diagram of the driving circuit provided by the embodiments of the present application is shown in the figure;

[0024] Figure 2 The circuit diagram of the power supply circuit provided by the embodiments of the present application is shown in the figure;

[0025] Figure 3 The circuit diagram of the voltage dividing circuit and the judgment circuit provided by the embodiments of the present application is shown in the figure;

[0026] Figure 4 The circuit diagram of the first switch circuit provided by the embodiments of the present application is shown in the figure;

[0027] Figure 5 The circuit diagram of the second switch circuit provided by the embodiments of the present application is shown in the figure;

[0028] Figure 6 The circuit diagram of the voltage boosting circuit provided by the embodiments of the present application is shown in the figure;

[0029] Figure 7 The circuit diagram of the voltage reducing circuit provided by the embodiments of the present application is shown in the figure;

[0030] Figure 8 The structural diagram of the LED circuit provided by the embodiments of the present application is shown in the figure.

[0031] C1, first capacitor; C2, second capacitor; C3, third capacitor; C4, fourth capacitor; C5, fifth capacitor; C6, sixth capacitor; C7, seventh capacitor; C8, eighth capacitor; C9, ninth capacitor; C10, tenth capacitor; C11, eleventh capacitor; C12, twelfth capacitor; C13, thirteenth capacitor; C14, fourteenth capacitor; C15, fifteenth capacitor; C16, sixteenth capacitor; C17, seventeenth capacitor; C24, twenty-fourth capacitor; C36, thirty-sixth capacitor; C37, thirty-seventh capacitor; C38, thirty-eighth capacitor; C40, fortieth capacitor; C41, forty-first capacitor; C59, fifty-ninth capacitor; C60, sixtieth capacitor;

[0032] L1, first inductor; L2, second inductor; L3, third inductor;

[0033] Q1, first field effect transistor; Q2, second field effect transistor; K1, first relay; K2, second relay; Q3, third triode; Q4, fourth triode;

[0034] U2, first constant current driver; U1, second constant current driver; U13, voltage stabilizing chip; U6, direct current converter;

[0035] R1, first resistor; R2, second resistor; R3, third resistor; R4, fourth resistor; R5, fifth resistor; R6, sixth resistor; R7, seventh resistor; R8, eighth resistor; R9, ninth resistor; R10, tenth resistor; R11, eleventh resistor; R12, twelfth resistor; R13, thirteenth resistor; R14, fourteenth resistor; R18, eighteenth resistor; R25, twenty-fifth resistor; R36, thirty-sixth resistor; R37, thirty-seventh resistor;

[0036] D1, first diode; D2, second diode; D3, third diode; D4, fourth diode; D5, fifth diode; D6, sixth diode; Z2, voltage stabilizing diode; CN1, interface. DETAILED DESCRIPTION

[0037] Embodiments of the present application will be described below in conjunction with the accompanying drawings. It should be understood that the embodiments described below in conjunction with the accompanying drawings are exemplary descriptions of the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions of the embodiments of the present application.

[0038] Those skilled in the art will understand that, unless otherwise stated, the singular forms "a," "an," "said," and "the" used herein may also include plural forms. It should be further understood that the terms "including" and "comprising" used in the embodiments of the present application mean that the corresponding features can be implemented as the presented features, information, data, steps, operations, elements, and / or components, but do not exclude implementation as other features, information, data, steps, operations, elements, components, and / or combinations thereof supported by the present technical field. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, the element can be directly connected or coupled to the other element, or it can refer to the element and the other element establishing a connection relationship through an intermediate element. In addition, the "connection" or "coupling" used herein may include wireless connection or wireless coupling. The term "and / or" used herein indicates at least one of the items defined by the term, for example, "A and / or B" indicates implementation as "A," or implementation as "A," or implementation as "A and B."

[0039] In order to make the purpose, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0040] The following describes several exemplary embodiments to illustrate the technical solutions of the embodiments of the present invention and the technical effects produced by the technical solutions of the present invention. It should be noted that the following embodiments can refer to, draw on, or combine with each other, and the same terms, similar features, and similar implementation steps in different embodiments will not be repeated.

[0041] The driving circuit and LED circuit provided in this application are intended to solve at least one technical problem existing in the prior art.

[0042] In an embodiment of the present application, a driving circuit is provided, such as Figures 1-7 As shown, the driving circuit includes a voltage divider circuit, a voltage comparison circuit, a boost circuit, and a buck circuit. The first output terminal of the voltage comparison circuit is connected to the boost circuit, and the second output terminal of the voltage comparison circuit is connected to the buck circuit. The output terminal of the boost circuit and the output terminal of the buck circuit are connected to the same load to be powered. The voltage divider terminal and the input terminal of the voltage divider circuit are respectively connected to the voltage comparison circuit. The voltage divider circuit is used to output the divided voltage of the external voltage at the input terminal through the voltage divider terminal. The voltage comparison circuit is used to compare the reference voltage with the divided voltage and transmit the external voltage at the input terminal to the boost circuit through the first output terminal when the divided voltage is lower than the reference voltage, and transmit the external voltage at the input terminal to the buck circuit through the second output terminal when the divided voltage is greater than or equal to the reference voltage. The output terminal of the boost circuit and the output terminal of the buck circuit output the same voltage, and the loads connected to the two can be different.

[0043] Optionally, the load can be a plurality of LEDs connected in series, or a single LED and other objects driven by power supply. The external voltage can be a direct current voltage, and accordingly, the load is an object working with direct current.

[0044] Optionally, the voltage dividing circuit comprises a thirteenth resistor R13 and a twenty-fifth resistor R25, the second end of the twenty-fifth resistor R25 is grounded, the first end of the twenty-fifth resistor R25 is connected with the voltage comparison circuit and the second end of the thirteenth resistor R13, and the first end of the thirteenth resistor R13 is connected with the external voltage; the voltage comparison circuit comprises a judging circuit provided with an operational amplifier, the non-inverting input end of the operational amplifier is connected with a reference voltage, and the inverting input end of the operational amplifier is connected with the second end of the thirteenth resistor R13.

[0045] In one embodiment, the voltage dividing circuit further comprises a tenth capacitor C10, the first end of the tenth capacitor C10 is grounded, and the second end of the tenth capacitor C10 is connected with the first end of the twenty-fifth resistor R25.

[0046] Optionally, the judging circuit can further comprise an eighteenth resistor R18, a twenty-fourth capacitor C24, a thirteenth capacitor C13 and a twelfth capacitor C12. The first end of the eighteenth resistor R18 is connected with the reference voltage, and the second end of the eighteenth resistor R18 is connected with the non-inverting input end of the operational amplifier. The first end of the thirteenth capacitor C13 is connected with the reference voltage and the first end of the twelfth capacitor C12. The second end of the thirteenth capacitor C13 is grounded and connected with the second end of the twelfth capacitor C12. The ground end of the operational amplifier is grounded, the voltage end of the operational amplifier is connected with the reference voltage and the first end of the twenty-fourth capacitor C24, and the second end of the twenty-fourth capacitor C24 is grounded.

[0047] In one embodiment, the model of the operational amplifier can be LMV321, and the voltage comparison is realized by the operational amplifier. The operational amplifier outputs a high level or a low level according to the voltage comparison result. Specifically, the reference voltage is 3.3V, that is, the voltage of the non-inverting input end of the operational amplifier is 3.3V, and the voltage of the inverting input end is the voltage of the external voltage divided by the thirteenth resistor R13 and the twenty-fifth resistor R25. By setting the resistance values of the thirteenth resistor R13 and the twenty-fifth resistor R25, the voltage of the inverting input end can be 3.333V when the external voltage is 40V, which is greater than 3.3V. Therefore, it can be concluded that: ① when the external voltage is greater than or equal to 40V, the voltage of the inverting input end is greater than 3.3V. ② when the external voltage is less than 40V, the voltage of the inverting input end is less than 3.3V. When the voltage of the non-inverting input end is lower than the voltage of the inverting input end, the output S_CON signal is low. When the voltage of the non-inverting input end is higher than the voltage of the inverting input end, the output S_CON signal is high. The S_CON signal can be used as a signal indicating the voltage comparison result.

[0048] Optionally, the voltage comparison circuit further comprises a first switch circuit provided with a third transistor Q3, a first relay K1 and a fourth diode D4, the base of the third transistor Q3 is connected with the output of the operational amplifier, the emitter of the third transistor Q3 is grounded, the collector of the third transistor Q3 is connected with the first end of the first relay K1 and the anode of the fourth diode D4, the cathode of the fourth diode D4 is connected with the fifth end of the first relay K1, the fifth end of the first relay K1 is connected with the working voltage, the fourth end of the first relay K1 is connected with the external voltage, the second end of the first relay K1 is connected with the second output of the voltage comparison circuit, and the third end of the first relay K1 is connected with the first output of the voltage comparison circuit. Wherein, the third transistor Q3 is cut off at low level and is turned on at high level, and when the first end and the fifth end of the first relay K1 are powered (i.e. the third transistor Q3 is turned on), the fourth end of the first relay K1 is connected with the third end, i.e. the external voltage is transmitted to the voltage boosting circuit. When the third transistor Q3 is cut off, the fourth end of the first relay K1 is connected with the second end, and the external voltage is transmitted to the voltage reducing circuit.

[0049] In one embodiment, the first switch circuit further comprises a tenth resistor R10 and a twelfth resistor R12, the first end of the tenth resistor R10 is connected with the output of the operational amplifier, the second end of the tenth resistor R10 is connected with the base of the third transistor Q3 and the first end of the twelfth resistor R12, and the second end of the twelfth resistor R12 is grounded and connected with the emitter of the third transistor Q3.

[0050] Optionally, the voltage comparison circuit further comprises a second switch circuit provided with a fourth transistor Q4, a sixth diode D6 and a second relay K2, the input of the fourth transistor Q4 is connected with the output of the operational amplifier, the emitter of the fourth transistor Q4 is grounded, the collector of the fourth transistor Q4 is connected with the anode of the sixth diode D6 and the first end of the second relay K2, the cathode of the sixth diode D6 is connected with the fifth end of the second relay K2, the fifth end of the second relay K2 is connected with the working voltage, the fourth end of the second relay K2 is grounded, the second end of the second relay K2 is connected with the negative electrode of the input of the voltage reducing circuit, and the third end of the second relay K2 is connected with the negative electrode of the input of the voltage boosting circuit.

[0051] Optionally, the model of the second relay K2 can be the same as the first relay K1, i.e. the working modes of the two are the same. Specifically, the models of the second relay K2 and the first relay K1 can be G2R-1-Z.

[0052] In one embodiment, as Figure 4 , Figure 5As shown, the second switch circuit can further include an eleventh resistor R11 and a fourteenth resistor R14, wherein a first end of the eleventh resistor R11 is connected to the output end of the operational amplifier, a second end of the eleventh resistor R11 is connected to the base of the fourth transistor Q4 and a first end of the fourteenth resistor R14, a second end of the fourteenth resistor R14 is grounded and connected to the emitter of the fourth transistor Q4. Specifically, the models of the first relay K1 and the second relay K2 are G2R-1-Z, when the external voltage is greater than or equal to 40V, the output S_CON signal is low, the S_CON signal is transmitted to the third transistor Q3 and the fourth transistor Q4, and the third transistor Q3 and the fourth transistor Q4 fail to be turned on, so that the first relay K1 and the second relay K2 are not opened, and the external voltage is supplied to the step-down circuit for use. The GND is connected to the JGND of the step-down driving LED circuit. When the external voltage is less than 40V, the output S_CON signal is high, the S_CON signal is transmitted to the third transistor Q3 and the fourth transistor Q4, so that the third transistor Q3 and the fourth transistor Q4 are turned on, and thus the first relay K1 and the second relay K2 are opened, the external voltage is supplied to the step-up circuit, and the GND is connected to the SGND of the step-up circuit.

[0053] Optionally, the driving circuit further includes a power supply circuit provided with a direct current converter U6, a thirty-sixth resistor R36 and a thirty-seventh resistor R37, an input end of the direct current converter U6 is connected to the external voltage, an output end of the direct current converter U6 is connected to a second end of the thirty-seventh resistor R37 and outputs the working voltage; a first end of the thirty-seventh resistor R37 is connected to a feedback end of the direct current converter U6 and a second end of the thirty-sixth resistor R36, and a first end of the thirty-sixth resistor R36 is grounded. The power supply circuit provides the working voltage required by the first relay K1 and / or the second relay K2 to work.

[0054] In one embodiment, the working voltage is 5V, and in order to achieve filtering, the power supply circuit further includes a thirty-sixth capacitor C36 and a fortieth capacitor C40, a first end of the thirty-sixth capacitor C36 is connected to an input end of the direct current converter U6 and a first end of the fortieth capacitor C40. A second end of the thirty-sixth capacitor C36 is connected to a second end of the fortieth capacitor C40, a grounding end and a switch end of the direct current converter U6. The model of the direct current converter U6 can be TD1601S-ADJ.

[0055] Optionally, the driving circuit can further include an interface CN1, a third end and a fourth end of the interface CN1 are grounded, a second end of the interface CN1 is connected to an input end of the direct current converter U6, and a first end of the interface CN1 is grounded. The external voltage is transmitted to the direct current converter U6 through the interface CN1.

[0056] Optionally, the power supply circuit further includes a voltage stabilizing chip U13, a fifty-ninth capacitor C59, and a sixtieth capacitor C60. The input end of the voltage stabilizing chip U13 is connected to the second end of the thirty-seventh resistor R37, the ground end of the voltage stabilizing chip U13 is grounded, the output end is connected to the first end of the fifty-ninth capacitor C59 and the first end of the sixtieth capacitor C60, and the second end of the fifty-ninth capacitor C59 and the second end of the sixtieth capacitor C60 are grounded. The voltage stabilizing chip U13 provides a reference voltage to the voltage comparison circuit.

[0057] Optionally, the model of the voltage regulator chip U13 may be AMS117-3.3V, and the voltage regulator chip U13 provides 3.3V direct current.

[0058] In one embodiment, Figure 2 As shown, the power supply circuit further includes a third inductor L3, a fifth diode D5, a forty-first capacitor C41, a thirty-seventh capacitor C37, a thirty-eighth capacitor C38, and an eleventh capacitor C11. The first end of the third inductor L3 is connected to the output end of the DC converter U6 and the cathode of the fifth diode D5. The anode of the fifth diode D5 is grounded and connected to the second end of the forty-first capacitor C41, the second end of the thirty-seventh capacitor C37, the second end of the thirty-eighth capacitor C38, and the second end of the eleventh capacitor C11. The first end of the third inductor L3 is connected to the second end of the thirty-seventh resistor R37, the first end of the forty-first capacitor C41, the first end of the thirty-seventh capacitor C37, the first end of the thirty-eighth capacitor C38, and the first end of the eleventh capacitor C11. The input voltage of the DC converter U6 in the power supply circuit is 9-60V, and it can adjust the output voltage to between 1.23V and 50V based on external voltage feedback and an internal reference voltage value. The 36th and 40th capacitors C36 and C40 function as filters. The output voltage can be calculated based on the resistance values ​​of the 37th and 36th resistors R37 and R36, using the formula: VOUT = 1.23 * (1 + R37 / R36). By adjusting the resistance values ​​of the 37th and 36th resistors R37 and R36, a voltage of 5V can be achieved. The fifth diode D5D5 is a freewheeling diode, and the third inductor L3 functions as energy storage. After filtering and energy storage by the 41st and 37th capacitors C37, C38, and C11, a stable DC output voltage is supplied to the voltage regulator chip U13, which directly converts the 5V voltage to 3.3V. The 59th and 60th capacitors C59 and C60 also function as filters, eliminating noise for the subsequent power supply circuit.

[0059] Optionally, the boost circuit comprises a first constant current driver U2, a second resistor R2, a fourth capacitor C4, a seventh capacitor C7, a first end of the second resistor R2 is connected with a positive pole of the first output end and a first end of the load, a second end is connected with a first end of the fourth capacitor C4 and an enable end of the first constant current driver U2, a second end of the fourth capacitor C4 is connected with a negative pole of the first output end, a second end of the seventh capacitor C7 and a ground pin of the first constant current driver U2, a first end of the seventh capacitor C7 is connected with a frequency compensation pin of the first constant current driver U2, and an output pin of the first constant current driver U2 is connected with a second end of the load.

[0060] Optionally, the load can be a series-connected diode, and a voltage drop generated by the load is 36V.

[0061] In an embodiment, the boost circuit further comprises a first inductor L1, a second capacitor C2, a fifteenth capacitor C15, a first diode D1, a sixteenth capacitor C16, a ninth capacitor C9, a ninth resistor R9, a seventh resistor R7, an eighth resistor R8, a third diode D3 and a second field effect transistor Q2. A first end of the second capacitor C2 is connected with a first end of the fifteenth capacitor C15, a first end of the second resistor R2 and a first end of the first inductor L1, and second ends of the second capacitor C2 and the fifteenth capacitor C15 are grounded. An anode of the first diode D1 is connected with a second end of the first inductor L1, and a cathode of the first diode D1 is connected with a first end of the sixteenth capacitor C16 and a first end of the load. A second end of the sixteenth capacitor C16 is grounded, a first end of the ninth capacitor C9 is connected with a turn-off time setting pin of the first constant current driver U2, and a second end is grounded. A second end of the ninth resistor R9 is grounded, and a first end is connected with a source of the second field effect transistor Q2 and an input current limit detection pin of the first constant current driver U2. A drain of the second field effect transistor Q2 is connected with the anode of the first diode D1 and the second end of the first inductor L1, and a gate is connected with a fifth pin of the first constant current driver U2 (the pin is used to drive the second field effect transistor Q2 to be turned on or turned off). A second end of the seventh resistor R7 is connected with a first end of the eighth resistor R8, an anode of the third diode D3 and a second end of the load, and a first end of the seventh resistor R7 is connected with a current feedback pin of the first constant current driver U2. A second end of the eighth resistor R8 and a second end of the third diode D3 are grounded.

[0062] Specifically, as Figure 6As shown, the model of the first constant current driver U2 can be TX6211, the input voltage can reach 3.6-100V, and the output voltage can vary in the range of greater than 0V and less than 120V. When the external voltage is less than 40V, the VM_BOOST of the boost circuit at this time is equal to VIN, and the boost circuit works normally. First, the voltage VM_BOOST is filtered by the second capacitor C2 and the fifteenth capacitor C15 to prevent the influence of voltage clutter on the later stage components, and VM_BOOST is supplied to the power input pin 8 of the first constant current driver U2 through a second resistor R2. The input voltage VDD of the first constant current driver U2 can be 5.5V, and the input current IVDD can be 2MA, so the resistance value related calculation formula of the second resistor R2 can be R2=(VM_BOOST-VDD) / 2MA. The pin 2 of the first constant current driver U2 U2(TX6211) is connected to VDD, and the enable end is effective at high level and is filtered by the fourth capacitor C4. Pin 3 is a frequency compensation pin, which is generally filtered by the seventh capacitor C7. Pin 7 is a turn-off time setting, and the value of the ninth capacitor C9 is generally 22-47PF. The second field effect transistor Q2 connected to pin 5 is an external MOS tube, the gate of the second field effect transistor Q2 is connected to an N-type MOS tube, the model of which can be NCEP11N10AK, and the withstand voltage VDS can reach 100V. The source of the second field effect transistor Q2 is connected to the pin 6 of the first constant current driver U2, and the pin 6 is an input current limiting detection pin connected to an overcurrent protection resistor (ninth resistor R9). The drain of the second field effect transistor Q2 is connected to the middle of the first inductor L1 and the first diode D1. When the second field effect transistor Q2 is turned on, the first inductor L1 is charged, and the inductor stores energy. When the second field effect transistor Q2 is turned off, the first inductor L1 discharges the load through the first diode D1, and the input voltage and the first inductor L1 together charge the capacitor to realize boost. And the eighth resistor R8 connected to pin 4 of the first constant current driver U2 can be used to realize constant current output. The output current IOUT=0.25V / R8. In a complete charging and discharging cycle, the energy stored in the inductor and the energy released are equal, but due to the inductor in series with the input voltage during discharging, the output voltage is raised.

[0063] Optionally, the voltage reduction circuit comprises a second constant current driver U1, a first resistor R1, a fifth resistor R5, a second diode D2, a first field effect transistor Q1, a third resistor R3, a fourth resistor R4, a sixth resistor R6, a voltage stabilizing diode Z2, a first end of the first resistor R1 is connected with a positive pole of the second output end and a drain of the first field effect transistor Q1, a second end of the first resistor R1 is connected with a voltage terminal of the second constant current driver U1 and a first end of the fifth capacitor C5, a second end of the fifth capacitor C5 is connected with a second end of the sixth capacitor C6, a second end of the fourth resistor R4 and a first end of the load, a first end of the sixth capacitor C6 is connected with a frequency compensation pin of the second constant current driver U1, a first end of the sixth resistor R6 is connected with the fourth pin, a second end of the sixth resistor R6 is connected with a cathode of the voltage stabilizing diode Z2, an anode of the voltage stabilizing diode Z2 is connected with a negative pole of the second output end and a second end of the load, a gate of the first field effect transistor Q1 is connected with a fifth pin of the second constant current driver U1, a source of the first field effect transistor Q1 is connected with a first end of the third resistor R3, and a second end of the third resistor R3 is connected with a current output pin of the second constant current driver U1 and a first end of the fourth resistor R4.

[0064] In one embodiment, the voltage reduction circuit can further comprise a first capacitor C1, a fourteenth capacitor C14, a fifth capacitor C5, a sixth capacitor C6, an eighth capacitor C8, a third capacitor C3, a second inductor L2, a seventeenth capacitor C17. A first end of the seventeenth capacitor C17 is connected with a first end of the load, a second end of the second inductor L2, an anode of the second diode D2 and a grounding pin of the second constant current driver U1. A second end of the seventeenth capacitor C17 is connected with a second end of the load and grounded. A first end of the second inductor L2 is connected with a second end of the fourth resistor R4, a second end of the third capacitor C3, a second end of the eighth capacitor C8, a second end of the fifth capacitor C5 and a second end of the sixth capacitor C6. A first end of the third capacitor C3 is connected with a seventh pin of the second constant current driver U1. A first end of the eighth capacitor C8 is connected with a fourth pin of the second constant current driver U1, a first end of the sixth capacitor C6 is connected with a third pin of the second constant current driver U1, and a first end of the fifth capacitor C5 is connected with a second end of the first resistor R1. A first end of the first capacitor C1 is connected with a first end of the fourteenth capacitor C14 and a first end of the first resistor R1, and a second end of the first capacitor C1 is grounded and connected with a second end of the fourteenth capacitor C14.

[0065] Specifically, as Figure 7As shown, the second constant current driver U1 can be a boost type, buck type high-power LED constant current driver with an external MOS tube, and its model can be TX6211. When the external voltage is greater than or equal to 40V, the VM_BUCK of the buck circuit at this time is equal to VIN, and the buck circuit works normally. First, the voltage VM_BUCK is filtered by the first capacitor C1 and the fourteenth capacitor C14 to prevent the voltage from affecting the subsequent components, and VM_BUCK is supplied to the power input pin (pin 8) of the second constant current driver U1 through the first resistor R1. If the input voltage VDD of the second constant current driver U1 is 5.5V and the input current IVDD is 2MA, then the resistance value of the first resistor R1 can be calculated as follows: R1 = (VM_BUCK-VDD) / 2MA.

[0066] The pin 2 of the second driver is connected to the load through the fifth resistor R5 and the second diode D2, and the enable end is high level effective. Pin 3 is a frequency compensation pin, which is filtered by the sixth capacitor C6. Pin 7 is a turn-off time setting, and the ninth capacitor C9 is 22-47PF. Pin 5 is connected to an N-type MOS tube (model NCEP11N10AK), and the drain of the N-type MOS tube is connected to VM_BUCK, and the source is connected to the second inductor L2 through the third resistor R3 and the fourth resistor R4. When the N-type MOS tube is turned on, VM_BUCK will be transmitted to the second inductor L2 through the N-type MOS tube, and the middle of the third resistor R3 and the fourth resistor R4 is connected to the pin 6 of the second constant current driver U1. At this time, pin 6 can be used to set the output current, and the calculation formula of the output current can be:

[0067] IOUT = 0.25 / [R3*R4 / (R3*R4)].

[0068] At this time, the pin 4 of the second constant current driver U1 is used as a normal pin, which is grounded through the sixth resistor R6 and the second diode D2 (which is a voltage stabilizing diode Z2). The seventeenth capacitor C17 has the function of storing energy to ensure continuous energy supply for the load.

[0069] In the driving circuit of the embodiment of the present application, the first output terminal of the voltage comparison circuit is connected to the boost circuit, and the second output terminal of the voltage comparison circuit is connected to the buck circuit; the output terminal of the boost circuit and the output terminal of the buck circuit are both connected to at least one load to be powered, and the driving voltage of the load is the same; the voltage divider terminal and the input terminal of the voltage divider circuit are respectively connected to the voltage comparison circuit, and the voltage divider circuit is used to output the divided voltage of the external voltage at the input terminal through the voltage divider terminal; the voltage comparison circuit is used to compare the reference voltage and the divided voltage and transmit the external voltage at the input terminal to the boost circuit through the first output terminal when the divided voltage is lower than the reference voltage, and transmit the external voltage at the input terminal to the buck circuit through the second output terminal when the divided voltage is greater than or equal to the reference voltage. The embodiment of the present application can control the boost circuit to perform a boost operation on the external voltage or use the buck circuit to perform a buck operation on the external voltage according to the change of the external voltage, thereby reducing the interference of the external voltage change on the load, effectively ensuring the normal operation of the device, and improving the safety and stability of the device.

[0070] According to one aspect of the embodiment of the present application, there is also provided an LED circuit, such as Figure 8 As shown, the load in the LED circuit is an LED lamp. The driving circuit as described in the above embodiment is connected to the LED lamp. The driving circuit converts the external voltage into a voltage matching the LED lamp and transmits it to the LED lamp.

[0071] The terms "first," "second," "third," "fourth," "1," "2," and the like (if any) in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or sequential sequence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the application described herein can be implemented in an order other than that shown or described in the drawings.

[0072] It should be understood that, although each operation step is indicated by arrows in the flowchart of the embodiment of the present application, the order of implementation of these steps is not limited to the order indicated by the arrows. Unless otherwise clearly stated herein, in some implementation scenarios of the embodiment of the present application, the implementation steps in each flowchart can be performed in other orders according to demand. In addition, some or all of the steps in each flowchart can include multiple sub-steps or multiple stages based on actual implementation scenarios. Some or all of these sub-steps or stages can be executed at the same time, and each sub-step or stage in these sub-steps or stages can also be executed at different times respectively. Under different scenarios at the execution time, the execution order of these sub-steps or stages can be flexibly configured according to demand, and the embodiment of the present application does not limit this.

[0073] The above is only optional implementation of part of the implementation scenarios of the present application. It should be pointed out that, for those skilled in the art, other similar implementation means based on the technical idea of the present application without departing from the technical concept of the present application also belong to the protection scope of the present application.

Claims

1. A driving circuit, characterized in that: It includes a voltage divider circuit, a voltage comparison circuit, a boost circuit and a buck circuit, wherein the first output end of the voltage comparison circuit is connected to the boost circuit, and the second output end of the voltage comparison circuit is connected to the buck circuit; The output end of the boost circuit and the output end of the buck circuit are connected to the same load to be powered; The voltage dividing end and the input end of the voltage dividing circuit are respectively connected to the voltage comparison circuit, and the voltage dividing circuit is used to output the divided voltage of the external voltage at the input end through the voltage dividing end; The voltage comparison circuit is used to compare the reference voltage and the divided voltage and, when the divided voltage is lower than the reference voltage, transmit the external voltage at the input end to the boost circuit through the first output end, and, when the divided voltage is greater than or equal to the reference voltage, transmit the external voltage at the input end to the step-down circuit through the second output end.

2. The driving circuit according to claim 1, wherein: The voltage divider circuit includes a thirteenth resistor and a twenty-fifth resistor, wherein the second end of the twenty-fifth resistor is grounded, the first end is connected to the voltage comparison circuit and the second end of the thirteenth resistor, and the first end of the thirteenth resistor is connected to the external voltage; The voltage comparison circuit includes a judgment circuit provided with an operational amplifier, wherein the non-inverting input terminal of the operational amplifier is connected to the reference voltage, and the inverting input terminal is connected to the second end of the thirteenth resistor.

3. The driving circuit according to claim 2, wherein: The voltage comparison circuit also includes a first switching circuit including a third transistor, a first relay, and a fourth diode. The base of the third transistor is connected to the output end of the operational amplifier, the emitter of the third transistor is grounded, the collector of the third transistor is connected to the first end of the first relay and the anode of the fourth diode, the cathode of the fourth diode is connected to the fifth end of the first relay, the fifth end of the first relay is connected to the working voltage, the fourth end of the first relay is connected to the external voltage, the second end of the first relay is connected to the second output end of the voltage comparison circuit, and the third end of the first relay is connected to the first output end of the voltage comparison circuit.

4. The driving circuit according to claim 2, wherein: The voltage comparison circuit also includes a second switching circuit including a fourth transistor, a sixth diode, and a second relay. The input end of the fourth transistor is connected to the output end of the operational amplifier, the emitter of the fourth transistor is grounded, the collector of the fourth transistor is connected to the anode of the sixth diode and the first end of the second relay, the cathode of the sixth diode is connected to the fifth end of the second relay, the fifth end of the second relay is connected to the operating voltage, the fourth end of the second relay is grounded, the second end is connected to the step-down circuit, and the third end is connected to the step-up circuit.

5. The driving circuit according to claim 3 or 4, characterized in that: The device further includes a power supply circuit including a DC converter, a thirty-sixth resistor, and a thirty-seventh resistor, wherein the DC converter has an input terminal connected to the external voltage, an output terminal connected to the second terminal of the thirty-seventh resistor, and outputs the operating voltage; The first end of the thirty-seventh resistor is connected to the feedback end of the DC converter and the second end of the thirty-sixth resistor, and the first end of the thirty-sixth resistor is grounded.

6. The driving circuit according to claim 5, wherein: The power supply circuit also includes a voltage stabilizing chip, a fifty-ninth capacitor, and a sixtieth capacitor. The input end of the voltage stabilizing chip is connected to the second end of the thirty-seventh resistor, the ground end of the voltage stabilizing chip is grounded, the output end is connected to the first end of the fifty-ninth capacitor and the first end of the sixtieth capacitor, and the second end of the fifty-ninth capacitor and the second end of the sixtieth capacitor are grounded.

7. The driving circuit according to claim 5, wherein: The power supply circuit also includes a third inductor, a fifth diode, a forty-first capacitor, a thirty-seventh capacitor, a thirty-eighth capacitor and an eleventh capacitor. The first end of the third inductor is connected to the output end of the DC converter and the cathode of the fifth diode. The anode of the fifth diode is grounded and connected to the second end of the forty-first capacitor, the second end of the thirty-seventh capacitor, the second end of the thirty-eighth capacitor and the second end of the eleventh capacitor. The first end of the third inductor is connected to the second end of the thirty-seventh resistor, the first end of the forty-first capacitor, the first end of the thirty-seventh capacitor, the first end of the thirty-eighth capacitor and the first end of the eleventh capacitor.

8. The driving circuit according to claim 1, wherein: The boost circuit includes a first constant current driver, a second resistor, a fourth capacitor, and a seventh capacitor. The first end of the second resistor is connected to the positive electrode of the first output terminal and the first end of the load, and the second end is connected to the first end of the fourth capacitor and the enable end of the first constant current driver. The second end of the fourth capacitor is connected to the negative electrode of the first output terminal, the second end of the seventh capacitor, and the ground pin of the first constant current driver. The first end of the seventh capacitor is connected to the frequency compensation pin of the first constant current driver, and the output pin of the first constant current driver is connected to the second end of the load.

9. The driving circuit according to claim 1, wherein: The step-down circuit includes a second constant current driver, a first resistor, a fifth resistor, a second diode, a first field-effect transistor, a third resistor, a fourth resistor, a sixth resistor, and a Zener diode. The first end of the first resistor is connected to the positive electrode of the second output terminal and the drain of the first field-effect transistor. The second end of the first resistor is connected to the voltage terminal of the second constant current driver and the first end of the fifth capacitor. The second end of the fifth capacitor is connected to the second end of the sixth capacitor, the second end of the fourth resistor, and the first end of the load. The first end of the sixth capacitor is connected to the frequency compensation pin of the second constant current driver. The first end of the sixth resistor is connected to the fourth pin of the second constant current driver. The second end of the sixth resistor is connected to the cathode of the Zener diode. The anode of the Zener diode is connected to the negative electrode of the second output terminal and the second end of the load. The gate of the first field-effect transistor is connected to the fifth pin of the second constant current driver. The source of the first field-effect transistor is connected to the first end of the third resistor. The second end of the third resistor is connected to the current output pin of the second constant current driver and the first end of the fourth resistor.

10. An LED circuit, characterized in that: The LED circuit includes the driving circuit according to any one of claims 1 to 9.

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