Driving circuit, light emitting diode and vehicle

Abstract

The present disclosure relates to a driving circuit comprising: a driving module configured to receive a driving control signal from a driving control terminal and output a driving voltage based on the driving control signal, the driving module comprising a first transistor; the current limiting module is configured to limit the current flowing through the driving module when the current flowing through the driving module exceeds a current threshold value, and the current limiting module comprises a first resistor and a second transistor; the first end of the first resistor is connected with the power supply input end of the driving circuit to receive a power supply voltage signal, the second end of the first resistor is connected with the control electrode of the second transistor and the first electrode of the first transistor, and the first electrode of the second transistor is connected with the first end of the first resistor; the second electrode is connected with the control electrode and the drive control end of the first transistor. The disclosure also relates to a light emitting diode and a vehicle.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of driving circuit, in particular to a driving circuit, a light-emitting diode and a vehicle. BACKGROUND

[0002] The driving circuit is connected between the power input end and the power load, and is an important component in electronic circuit technology.

[0003] For a specific power load, such as a light-emitting diode (LED), the application cannot be separated from the required driving circuit. Through the driving circuit, a good and stable current is obtained, so that the power load runs more stably, for example, so that the light-emitting diode display is more uniform and beautiful, meeting the application requirements of various occasions.

[0004] In actual application, the driving circuit may face the risk of overcurrent, which brings risk to the electronic devices in the driving circuit or even the power load. UTILITY MODEL CONTENT

[0005] Embodiments of the present disclosure provide a driving circuit, a light-emitting diode and a vehicle. The driving circuit, the light-emitting diode and the vehicle realize the driving circuit with current limiting function, so that the operation of the driving circuit is more stable and reliable. In addition, the driving circuit is easier to realize in structure, has lower cost, and has better use and manufacturing advantages.

[0006] Embodiments of the present disclosure provide a driving circuit, wherein the driving circuit comprises:

[0007] a driving module configured to receive a driving control signal from a driving control end and output a driving voltage based on the driving control signal, wherein the driving module comprises a first transistor; and

[0008] a current limiting module configured to limit the current flowing through the driving module when the current flowing through the driving module exceeds a current threshold, wherein the current limiting module comprises a first resistor and a second transistor.

[0009] Wherein the first end of the first resistor is connected with the power input end of the driving circuit to receive a power voltage signal, the second end is connected with the control electrode of the second transistor and the first electrode of the first transistor, the first electrode of the second transistor is connected with the first end of the first resistor, and the second electrode is connected with the control electrode of the first transistor and the driving control end.

[0010] According to an embodiment of the present disclosure, the first transistor is a bipolar transistor, wherein the first electrode of the first transistor is an emitter, the second electrode is a collector, and the control electrode is a base; or the first transistor is a MOS transistor, wherein the first electrode of the first transistor is a source, the second electrode is a drain, and the control electrode is a gate.

[0011] According to an embodiment of the present disclosure, the second transistor is a bipolar transistor, wherein the first electrode of the second transistor is an emitter, the second electrode is a collector, and the control electrode is a base; or the second transistor is a MOS transistor, wherein the first electrode of the second transistor is a source, the second electrode is a drain, and the control electrode is a gate.

[0012] According to an embodiment of the present disclosure, the driving circuit further comprises a starting module configured to provide the driving control signal, wherein the starting module has a second resistor, a first end of the second resistor is connected with the driving control end, and a second end is connected with a control input end configured to provide a control input signal.

[0013] According to an embodiment of the present disclosure, the driving circuit further comprises a starting module configured to provide the driving control signal, wherein the starting module has a third transistor, a first electrode of the third transistor is connected with the driving control end, a second electrode is connected with a reference potential, and a control electrode is connected with a control input end configured to provide a control input signal.

[0014] According to an embodiment of the present disclosure, the third transistor is a bipolar transistor, wherein the first electrode of the third transistor is a collector, the second electrode is an emitter, and the control electrode is a base; or the third transistor is a MOS transistor, wherein the first electrode of the third transistor is a drain, the second electrode is a source, and the control electrode is a gate.

[0015] An embodiment of the present disclosure provides a light-emitting diode having the driving circuit according to one of the embodiments of the present disclosure as a driving circuit.

[0016] An embodiment of the present disclosure provides a vehicle having the light-emitting diode according to one of the embodiments of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings needed to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some example embodiments of the present disclosure, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0018] Figure 1A schematic diagram of a drive circuit according to an embodiment of the present disclosure is shown.

[0019] Figure 2 A schematic diagram of a drive circuit according to another embodiment of the present disclosure is shown.

[0020] Figure 3 A schematic diagram of a drive circuit according to another embodiment of the present disclosure is shown.

[0021] Figure 4 An application schematic diagram of a drive circuit according to an embodiment of the present disclosure is shown; and

[0022] Figure 5 An application schematic diagram of a drive circuit according to another embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0023] In order to make the objectives, technical solutions and advantages of the present disclosure more obvious, the following will describe the example embodiments according to the present disclosure in detail with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure, and it should be understood that the present disclosure is not limited to the example embodiments described herein.

[0024] In the present specification and drawings, the steps and elements with substantially the same or similar functions are denoted by the same or similar reference signs, and the repeated description of these steps and elements will be omitted. Meanwhile, in the description of the present disclosure, the terms “first”, “second”, etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance or sequence.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure belongs. The terms used herein are only for the purpose of describing the embodiments of the present disclosure, and are not intended to limit the present disclosure.

[0026] Figure 1 A schematic diagram of a drive circuit according to an embodiment of the present disclosure is shown.

[0027] As Figure 1 shown, the drive circuit DC according to the embodiments of the present disclosure may, for example, include a drive module DM and a current limiting module LM.

[0028] The drive module DM may, for example, be configured to receive a drive control signal from a drive control terminal PC, and output a drive voltage based on the drive control signal, for example, at an output terminal P2.

[0029] The drive circuit DC may, for example, be connected with an electrical load via the output terminal P2, so as to provide the drive voltage to the electrical load.

[0030] The driving module DM may, for example, comprise a first transistor Q1. The operating state of the first transistor Q1 is controlled by means of a driving control signal received via a driving control terminal PC. The driving control signal is, for example, a high level or a low level.

[0031] The current-limiting module LM may, for example, be configured to limit the current flowing through the driving module DM when the current flowing through the driving module DM exceeds a current threshold value.

[0032] The current threshold value may, for example, be set according to the hardware design of the electrical load, the electronic devices in the circuit, or according to user requirements. In the event of a fault, for example a short circuit, on the electrical load side circuit or the driving circuit DC side, or in the event of a change in the power consumption of the electrical load, for example the parallel connection of more electrical loads, there is a risk that the current flowing through the driving module DM will exceed the current threshold value.

[0033] By means of the current-limiting module LM, even in the event of a current flowing through the driving module DM exceeding the current threshold value, the current flowing through the driving module DM can be limited, so that the current flowing through the driving module DM, or the current supplied to the electrical load side, is always kept within a certain current threshold value, improving the safety and reliability of the driving circuit DC and reducing the use cost of the electrical load, which can be costly.

[0034] The current-limiting module LM may, for example, comprise a first resistor R1 and a second transistor Q2.

[0035] For example, the first end of the first resistor R1 may be connected to the power input terminal P1 of the driving circuit DC to receive a power voltage signal, and the second end may be connected to the control electrode of the second transistor Q2 and the driving module DM, preferably the first electrode of the first transistor Q1.

[0036] The driving circuit DC may, for example, be connected to a power supply via the power input terminal P1, and the electrical load is driven by means of a power voltage signal provided by the power supply, the power voltage signal being a high level, for example 13.5V or the like.

[0037] For example, the first electrode of the second transistor Q2 may be connected to the first end of the first resistor R1 or the power input terminal P1, the second electrode may be connected to the driving module DM, preferably the control electrode of the first transistor Q1 and the driving control terminal PC, and the control electrode may be connected to the second end of the first resistor R1.

[0038] Preferably, the first transistor Q1 is a bipolar transistor, wherein the first electrode of the first transistor Q1 is the emitter electrode, the second electrode is the collector electrode, and the control electrode is the base electrode.

[0039] Correspondingly, the emitter of the first transistor Q1 can be connected with the second end of the first resistor R1 and the control electrode of the second transistor Q2, the collector can be connected with the output terminal P2, and the base can be connected with the driving control terminal PC to receive the driving control signal.

[0040] Preferably, the second transistor Q2 is a bipolar transistor, wherein the first electrode of the second transistor Q2 is the emitter, the second electrode is the collector, and the control electrode is the base.

[0041] Correspondingly, the emitter of the second transistor Q2 can be connected with the first end of the first resistor R1 or the power input terminal P1, the collector can be connected with the control electrode of the first transistor Q1 and the driving control terminal PC, and the base can be connected with the second end of the first resistor R1.

[0042] When the driving circuit DC and the electrical load are normally operated, the driving circuit DC or the driving module DM outputs a driving voltage, for example, a high-level (for example, 13.5V, 15V, etc.) power voltage signal received from the power input terminal P1 provided by the power supply, and a low-level (for example, 3.3V, 0V, etc.) driving control signal received from the driving control terminal PC, so that the first transistor Q1 of the driving module DM is turned on.

[0043] At the same time, the resistance value of the first resistor R1 is designed in this way, so that the voltage drop across the first resistor R1 does not exceed the turn-on voltage (for example, about 0.7V) of the second transistor Q2 in normal operation. As known from the above, the first electrode (here, the emitter) of the second transistor Q2 is connected with the first end of the first resistor R1, and the control electrode (here, the base) of the second transistor Q2 is connected with the second end of the first resistor R1. Therefore, when the driving circuit DC and the electrical load are normally operated, the voltage difference Veb between the emitter and the base of the second transistor Q2 does not reach the turn-on voltage, that is, the second transistor Q2 is not turned on.

[0044] However, in the case that a current change occurs on the side of the driving circuit DC or the electrical load and the current flowing through the driving module DM exceeds the current threshold value, the voltage drop across the first resistor R1 increases and exceeds the turn-on voltage of the second transistor Q2, the voltage difference Veb between the emitter and the base of the second transistor Q2 reaches the turn-on voltage, the PN junction is turned on, and the second transistor Q2 is turned on.

[0045] After the second transistor Q2 is turned on, the voltage difference Veb between the emitter and the base of the second transistor Q2 remains the turn-on voltage, that is, the voltage drop across the first resistor R1 remains the turn-on voltage, and in this case, the current flowing through the driving module DM is the quotient of the turn-on voltage of the second transistor Q2 and the resistance value of the first resistor R1.

[0046] In this way, the maximum current flowing through the driving module DM is the quotient of the on-voltage of the second transistor Q2 and the resistance value of the first resistor R1. For example, if the on-voltage of the second transistor Q2 is 0.7V, the maximum current flowing through the driving module DM is 0.7 / R1, and the driving circuit DC achieves current limiting.

[0047] After the second transistor Q2 is turned on, since the second electrode (here, the collector) of the second transistor Q2 is connected to the control electrode (here, the base) of the first transistor Q1, the voltage at the control electrode of the first transistor Q1 rises and approaches the voltage at the first electrode of the second transistor Q2, the current at the control electrode of the first transistor Q1 decreases, and the first transistor Q1 changes from the saturation on-state to the amplification on-state, for example, and the voltage drop between the emitter and the collector of the first transistor Q1 rises. In the saturation on-state, the voltage drop between the emitter and the collector of the first transistor Q1 is small (for example, 0.1V).

[0048] In this way, when the current flowing through the driving module DM exceeds the current threshold, the voltage drop on the first resistor R1 (and correspondingly, the current flowing through the first resistor R1) is limited by the second transistor Q2, the operating state of the first transistor Q1 is controlled, so that there is a larger voltage drop between the first electrode and the second electrode of the first transistor Q1 than in normal operation, which is conducive to further reducing the current flowing through the driving module DM.

[0049] For example, after taking circuit protection measures, the current flowing through the driving module DM decreases, the voltage drop across the first resistor R1 decreases to less than the on-voltage of the second transistor Q2, the voltage difference Veb between the emitter and the base of the second transistor Q2 no longer reaches the on-voltage, the PN junction is not conductive, and the second transistor Q2 is turned off.

[0050] Whether in normal operation or in abnormal operation where the current flowing through the driving module DM is greater than the current threshold, the current flowing through the driving module DM can be limited to be less than or equal to the quotient of the on-voltage of the second transistor Q2 and the resistance value of the first resistor R1, current limiting of the electrical load is achieved, and the safety and operation stability of the electrical load are improved.

[0051] Compared with the driving circuit and / or current limiting module using a current mirror, the driving circuit structure according to the embodiment of the present disclosure is simpler and has lower cost.

[0052] Figure 2 A schematic diagram of a driving circuit according to another embodiment of the present disclosure is shown.

[0053] As Figure 2As shown, the first transistor Q1 may, for example, be a MOS transistor (MOSFET, Metal Oxide Semiconductor Field Effect Transistor), in which the first pole is the source, the second pole is the drain, and the control pole is the gate.

[0054] Correspondingly, the source of the first transistor Q1 may be connected with the second end of the first resistor R1 and the control pole of the second transistor Q2, the drain may be connected with the output end P2, and the base may be connected with the driving control end PC to receive the driving control signal.

[0055] For example, the power voltage signal at a high level (e.g., 13.5V, 15V, etc.) provided by the power supply may be received from the power input end P1, and the driving control signal at a low level (e.g., 3.3V, 0V, etc.) may be received from the driving control end PC, so that the first transistor Q1 of the driving module DM is turned on.

[0056] Figure 3 A schematic diagram of a driving circuit according to another embodiment of the present disclosure is shown.

[0057] As Figure 3 As shown, the second transistor Q2 may, for example, be a MOS transistor, in which the first pole is the source, the second pole is the drain, and the control pole is the gate.

[0058] Correspondingly, the source of the second transistor Q2 may be connected with the first end of the first resistor R1 or the power input end P1, the drain may be connected with the control pole of the first transistor Q1 and the driving control end PC, and the gate may be connected with the second end of the first resistor R1.

[0059] The resistance value of the first resistor R1 is designed in this way so that the voltage drop across the first resistor R1 does not exceed the turn-on voltage (e.g., about 2V) of the second transistor Q2 (here, a MOS transistor) in normal operation. As known from the above, the first pole (here, the source) of the second transistor Q2 is connected with the first end of the first resistor R1, and the control pole (here, the gate) of the second transistor Q2 is connected with the second end of the first resistor R1. Thus, when the driving circuit DC and the electrically loaded load are in normal operation, the voltage difference Vsg between the source and the gate of the second transistor Q2 does not reach the turn-on voltage, i.e., the second transistor Q2 is not turned on.

[0060] However, in the case of a current change on the side of the driving circuit DC or the electrically loaded load and the current flowing through the driving module DM exceeds the current threshold, the voltage drop across the first resistor R1 increases and exceeds the turn-on voltage of the second transistor Q2, the voltage difference Vsg between the source and the gate of the second transistor Q2 reaches the turn-on voltage, and the second transistor Q2 is turned on.

[0061] For example, after taking the circuit protection measure, the current flowing through the drive module DM is reduced, the voltage drop across the first resistor R1 is reduced to be less than the turn-on voltage of the second transistor Q2, the voltage difference Vsg between the source and the gate of the second transistor Q2 does not reach the turn-on voltage, and the second transistor Q2 is turned off.

[0062] In both normal operation and abnormal operation in which the current flowing through the drive module DM is greater than the current threshold, the current flowing through the drive module DM can be limited to be less than the quotient of the turn-on voltage of the second transistor Q2 and the resistance value of the first resistor R1, thereby achieving current limiting of the electrical load and improving the safety and operation stability of the electrical load.

[0063] According to an embodiment of the present disclosure, the first transistor Q1 and the second transistor Q2 can both be bipolar transistors (see Figure 1 ) or MOS transistors (not shown), or one of them is a bipolar transistor and the other is a MOS transistor (see Figure 2 、 Figure 3 ).

[0064] Preferably, the bipolar transistor is more cost-effective than the MOS transistor.

[0065] Figure 4 An application schematic diagram of the drive circuit according to an embodiment of the present disclosure is shown.

[0066] As Figure 4 shown, the drive circuit DC further includes a start-up module IM configured to provide the drive control signal.

[0067] According to an embodiment of the present disclosure, the start-up module IM can have a second resistor R2, a first end of the second resistor R2 can be connected with the drive control end PC, and a second end is connected with the control input end P3.

[0068] The control input end P3 can be connected with a reference potential, for example, can be a ground potential, or can be other potentials that can meet the control of the control electrode of the first transistor Q1. Alternatively, the control input end can receive an input control signal, for example, can be a pulse form control signal.

[0069] In Figure 4 the embodiment shown, the start-up module IM only has the second resistor R2, and the drive control end PC is connected with the reference potential via the second resistor R2. Taking the second resistor R2 grounded as an example, the resistance value of the second resistor R2 is set in such a way that the required drive control signal, for example, a low level, is always provided at the drive control end PC.

[0070] In this case, the drive module DM will always be in the on state after a high-level power supply voltage signal is provided at the power supply input.

[0071] The output P2 of the drive circuit DC can be connected to the first capacitor C1 and to the consumer load R, for example. The first capacitor C1 and the consumer load R are connected in parallel. The first capacitor C1 can be used to implement a voltage stabilization, for example.

[0072] An embodiment according to the present disclosure provides a drive circuit which is simple in structure and low in cost. The embodiment is advantageous in the case where the consumer load R only has to be controlled to be switched on.

[0073] Figure 5 An application diagram of a drive circuit according to another embodiment of the present disclosure is shown.

[0074] As Figure 5 shown, the drive circuit DC further comprises an initiation module IM which is configured to provide the drive control signal.

[0075] The initiation module IM can have a third transistor Q3, for example, wherein a first pole of the third transistor Q3 is connected to the drive control terminal PC, for example via a second resistor R2, a second pole is connected to a reference potential, and a control pole is connected to the control input P3, for example via a third resistor R3.

[0076] The control input P3 is used to provide a control input signal, for example a low-level signal, for driving the third transistor Q3, for example.

[0077] A first end of the third resistor R3 is connected to the control input P3 in order to receive the control input signal, and a second end is connected to a first end of a fourth resistor R4 and to the control pole of the third transistor Q3. A second end of the fourth resistor R4 is connected to a reference potential, for example ground potential. The third resistor R3 and the fourth resistor R4 are used to stably provide a voltage signal for the control pole of the third transistor Q3.

[0078] According to an embodiment of the present disclosure, the third transistor Q3 can be a bipolar transistor, for example, wherein the first pole of the third transistor Q3 is the collector, the second pole is the emitter, and the control pole is the base.

[0079] Accordingly, the collector of the third transistor Q3 is connected to the drive control terminal PC via the second resistor R2, the emitter is connected to the reference potential, and the base is connected to the control input P3 via the third resistor R3.

[0080] After a control input signal, for example 3.3 V, is provided at the control input P3, the voltage difference Vbe between the base and the emitter of the third transistor Q3 reaches the turn-on voltage, the third transistor Q3 is turned on, and a drive control signal is provided for the first transistor Q1 via the drive control terminal PC. In the presence of the supply voltage signal, the first transistor Q1 is turned on, and the powered load R is powered on.

[0081] If no control input signal is provided at the control input P3, the voltage difference Vbe between the base and the emitter of the third transistor Q3 does not reach the turn-on voltage, the third transistor Q3 is turned off, no drive control signal can be provided for the first transistor Q1 via the drive control terminal PC, the first transistor Q1 is turned off, and the powered load R is powered off.

[0082] By controlling whether a control input signal is provided or not, the turn-on and turn-off of the drive circuit DC is achieved in a simple and reliable manner.

[0083] According to embodiments of the present disclosure, the third transistor Q3 can be a MOS transistor, for example, wherein the first pole of the third transistor is the drain, the second pole is the source, and the control pole is the gate.

[0084] Accordingly, the drain of the third transistor Q3 is connected to the drive control terminal PC via the second resistor R2, the source is connected to the reference potential, and the gate is connected to the control input P3 via the third resistor R3.

[0085] Embodiments of the present disclosure also provide a light emitting diode having a drive circuit according to embodiments of the present disclosure as the drive circuit. In this way, a light emitting diode that operates more stably is obtained. For details, reference is made to the above description of the drive circuit according to embodiments of the present disclosure, which will not be repeated here for brevity.

[0086] Embodiments of the present disclosure also provide a vehicle having a light emitting diode and / or a drive circuit according to embodiments of the present disclosure. For details, reference is made to the above description of the drive circuit according to embodiments of the present disclosure, which will not be repeated here for brevity.

[0087] In general, the various example embodiments of the present disclosure can be implemented in hardware or special-purpose circuits, software, firmware, logic, or any combination thereof. Some aspects can be implemented in hardware, while other aspects can be implemented in firmware or software which can be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it will be understood that the blocks, apparatus, systems, techniques or methods described herein can be implemented in hardware, software, firmware, special-purpose circuits or logic, general purpose hardware or controlers or other computing devices, or some combination thereof.

[0088] The example embodiments of the present disclosure described above are merely illustrative, rather than limiting on the present disclosure. It should be understood by those skilled in the art that various modifications and combinations can be made to these embodiments or features in their characteristics, and such modifications should fall within the scope of the present disclosure.

Claims

1. A drive circuit characterized by comprising: The driving circuit comprises: a driving module configured to receive a driving control signal from a driving control terminal and output a driving voltage based on the driving control signal, wherein the driving module comprises a first transistor; and a current limiting module configured to limit a current flowing through the driving module when the current flowing through the driving module exceeds a current threshold, wherein the current limiting module comprises a first resistor and a second transistor; and wherein a first end of the first resistor is connected to a power input terminal of the driving circuit to receive a power voltage signal, a second end of the first resistor is connected to a control electrode of the second transistor and a first electrode of the first transistor, a first electrode of the second transistor is connected to the first end of the first resistor, and a second electrode of the second transistor is connected to a control electrode of the first transistor and the driving control terminal.

2. The driving circuit of claim 1, wherein the first transistor is a bipolar transistor, wherein a first electrode of the first transistor is an emitter, a second electrode of the first transistor is a collector, and a control electrode of the first transistor is a base; or the first transistor is a MOS transistor, wherein a first electrode of the first transistor is a source, a second electrode of the first transistor is a drain, and a control electrode of the first transistor is a gate.

3. The driving circuit of claim 1, wherein the second transistor is a bipolar transistor, wherein a first electrode of the second transistor is an emitter, a second electrode of the second transistor is a collector, and a control electrode of the second transistor is a base; or the second transistor is a MOS transistor, wherein a first electrode of the second transistor is a source, a second electrode of the second transistor is a drain, and a control electrode of the second transistor is a gate.

4. The drive circuit according to claim 1, characterized by The driving circuit further comprises: a starting module configured to provide the driving control signal, wherein the starting module has a second resistor, a first end of the second resistor is connected to the driving control terminal, and a second end of the second resistor is connected to a control input terminal configured to provide a control input signal.

5. The drive circuit according to claim 1, characterized by The driving circuit further comprises: a starting module configured to provide the driving control signal, wherein the starting module has a third transistor, a first electrode of the third transistor is connected to the driving control terminal, a second electrode of the third transistor is connected to a reference potential, and a control electrode of the third transistor is connected to a control input terminal configured to provide a control input signal.

6. The driving circuit of claim 5, wherein the third transistor is a bipolar transistor, wherein a first electrode of the third transistor is a collector, a second electrode of the third transistor is an emitter, and a control electrode of the third transistor is a base; or the third transistor is a MOS transistor, wherein a first electrode of the third transistor is a drain, a second electrode of the third transistor is a source, and a control electrode of the third transistor is a gate.

7. A light-emitting diode, characterized in that, The light emitting diode has the driving circuit according to any one of claims 1 to 6 as a driving circuit.

8. A vehicle characterized by comprising: The vehicle has the light emitting diode according to claim 7.

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