Driving circuit capable of rapidly turning off auxiliary source and emergency power supply

Abstract

The utility model relates to a drive circuit capable of rapidly turning off an auxiliary source and an emergency power supply. The drive circuit comprises an EMI filtering module, a rectification filtering module, an intermediate processing module, an output module, the auxiliary source and a dimming control module. The EMI filtering module, the rectification filtering module, the intermediate processing module and the output module are connected in sequence. The power supply input end of the auxiliary source is arranged between the output end of the rectification filtering module and the input end of the intermediate processing module. The EMI filtering module is used for being connected with an external power supply, accessing an AC signal and carrying out EMI filtering processing on the AC signal; the rectifying and filtering module is used for performing rectifying and filtering processing on the AC signal and then providing an input signal and a power supply signal to the intermediate processing module and the auxiliary source respectively; and the auxiliary source is used for providing electric energy for the intermediate processing module and the dimming control module during normal work, and is quickly turned off when the AC signal is cut off. According to the utility model, the auxiliary power supply can be quickly switched off during AC power failure, and the requirement of quick switching is met.

Description

Technical Field

[0001] This utility model relates to the technical field of drive power supplies, and more specifically, to a drive circuit and emergency power supply for quickly shutting off auxiliary sources. Background Technology

[0002] An independent auxiliary power supply circuit is an important component in LED driver power supply design, improving system stability, reliability, and functional scalability. This circuit typically provides stable power to low-power circuits such as control circuits, MCUs (microcontrollers), and feedback loops within the driver power supply. This allows the main circuit to continue operating stably during startup or under special conditions (such as sudden load changes or failures).

[0003] In some applications, it is necessary for the drive power supply to shut down quickly, thereby rapidly cutting off the auxiliary power supply. For example, in the use of emergency power supplies, a rapid shutdown is required to quickly cut off the auxiliary power supply, thus ceasing to supply power to equipment connected to the auxiliary power supply and releasing a dimming light to receive control signals from the emergency power supply.

[0004] However, in the existing design, the startup circuit of the auxiliary power supply / the power supply circuit of the auxiliary power supply main control IC is connected to the output of the PFC circuit. Because there is a large electrolytic capacitor at the output of the PFC circuit, when the drive power supply is shut down quickly, such as when the AC power is cut off, the auxiliary power supply cannot achieve rapid power-off and continue to supply power output due to the presence of the large electrolytic capacitor, which cannot meet the requirements of rapid switching. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a drive circuit and emergency power supply for quickly shutting off the auxiliary source, addressing the problems existing in the prior art.

[0006] The technical solution adopted by this utility model to solve its technical problem is: to construct a driving circuit for quickly shutting off the auxiliary source, including: an EMI filter module, a rectification filter module, an intermediate processing module, an output module, an auxiliary source, and a dimming control module;

[0007] The EMI filter module, the rectifier filter module, the intermediate processing module, and the output module are connected in sequence. The auxiliary source is connected to the intermediate processing module and the dimming control module respectively, and the power supply input terminal of the auxiliary source is located between the output terminal of the rectifier filter module and the input terminal of the intermediate processing module.

[0008] The EMI filtering module is used to connect to an external power supply, to receive AC signals, and to perform EMI filtering on the AC signals.

[0009] The rectification and filtering module is used to rectify and filter the AC signal and then provide input signals and power supply signals to the intermediate processing module and the auxiliary source, respectively.

[0010] The auxiliary source is used to provide power to the intermediate processing module and the dimming control module during normal operation, and to quickly shut down when the AC signal is cut off.

[0011] In the driving circuit for the fast shutdown auxiliary source described in this utility model, the auxiliary source includes: an input module, a linear voltage regulator module, a stable power supply module, an isolation module, and a control chip;

[0012] The input terminal of the input module is connected to the output terminal of the rectifier and filter module, the first output terminal of the input module is connected to the power supply terminal of the control chip, the second output terminal of the input module is connected to the drive terminal of the linear regulator module, the input terminal of the linear regulator module is connected to the stable power supply module, the output terminal of the linear regulator module is connected to the input terminal of the isolation module, and the output terminal of the isolation module is connected to the power supply terminal of the control chip.

[0013] The input module is used to process the voltage provided by the output terminal of the rectifier and filter module, provide a start-up voltage to the control chip, and provide a drive signal to the linear regulator module after the control chip starts working, and quickly stop outputting the drive signal when the AC signal is cut off;

[0014] The linear voltage regulator module is used to provide the operating voltage to the control chip through the isolation module after the driving signal is turned on and the operating signal provided by the stable power supply module is regulated, and to cut off the operating signal according to the control of the input module when the AC signal is cut off.

[0015] In the driving circuit for the fast shutdown auxiliary source described in this utility model, the input module includes: a current limiting circuit, a clamping circuit, and a filtering circuit;

[0016] The input terminal of the current limiting circuit is connected to the output terminal of the rectifier and filter module, the first output terminal of the current limiting circuit is connected to the input terminal of the clamping circuit, and the second output terminal of the current limiting circuit is connected to the control terminal of the linear regulator module.

[0017] The output of the clamping circuit is connected to the filter circuit and then to the power supply of the control chip.

[0018] In the driving circuit for the fast shutdown auxiliary source described in this utility model, the current limiting circuit includes: a tenth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a second resistor.

[0019] The tenth resistor, the sixth resistor, the seventh resistor, the eighth resistor, and the second resistor are connected in series between the output terminal of the rectifier filter module and the control terminal of the linear regulator module.

[0020] The connection node between the eighth resistor and the second resistor is the first output terminal of the current limiting circuit, and the connection node between the second resistor and the control terminal of the linear voltage regulator module is the second output terminal of the current limiting circuit.

[0021] In the drive circuit for the rapid shutdown auxiliary source described in this utility model, the clamping circuit includes: a first Zener diode;

[0022] The cathode of the first Zener diode is the input terminal of the clamping circuit, and the anode of the first Zener diode is the output terminal of the clamping circuit.

[0023] In the driving circuit for quickly shutting off the auxiliary source described in this utility model, the filtering circuit includes: a first filtering capacitor;

[0024] The first end of the first filter capacitor is connected to the anode of the first Zener diode and to the power supply terminal of the control chip, and the second end of the first filter capacitor is grounded.

[0025] In the driving circuit for the fast shutdown auxiliary source described in this utility model, the linear voltage regulator module includes: a first resistor, a second Zener diode, a second filter capacitor, and a transistor;

[0026] The first end of the first resistor is connected to the base of the transistor, the second end of the first resistor is connected to the second output terminal of the input module, the cathode of the second Zener diode is connected to the second end of the first resistor, and the anode of the second Zener diode is grounded.

[0027] The collector of the transistor is connected to the stable power supply module, and the emitter of the transistor is connected to the isolation module.

[0028] In the drive circuit for the fast shutdown auxiliary source described in this utility model, the stable power supply module includes: a transformer, a second diode, and a third capacitor;

[0029] The first terminal of the transformer is connected to the anode of the second diode, the second terminal of the transformer is grounded, the cathode of the second diode is connected to the collector of the transistor and the first terminal of the third capacitor, and the second terminal of the third capacitor is grounded.

[0030] In the driving circuit for rapid shutdown of the auxiliary source described in this utility model, the isolation module includes: a first diode;

[0031] The anode of the first diode is connected to the emitter of the transistor, and the cathode of the first diode is connected to the first output terminal of the input module.

[0032] This utility model also provides an emergency power supply, including: the drive circuit for quickly shutting off the auxiliary source as described above.

[0033] The driving circuit and emergency power supply for quickly shutting off the auxiliary power source according to this invention have the following beneficial effects: It includes an EMI filter module, a rectifier filter module, an intermediate processing module, an output module, an auxiliary power source, and a dimming control module. The EMI filter module, rectifier filter module, intermediate processing module, and output module are connected sequentially. The power input terminal of the auxiliary power source is located between the output terminal of the rectifier filter module and the input terminal of the intermediate processing module. The EMI filter module is used to connect to an external power supply, to receive AC signals, and to perform EMI filtering on the AC signals. The rectifier filter module is used to rectify and filter the AC signals and then provide input signals and power supply signals to the intermediate processing module and the auxiliary power source, respectively. The auxiliary power source is used to provide power to the intermediate processing module and the dimming control module during normal operation, and to quickly shut down when the AC signal is cut off. This invention can quickly shut down the auxiliary power supply when the AC power is lost, meeting the need for rapid switching. Attached Figure Description

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0035] Figure 1 This is a schematic block diagram of the driving circuit for the rapid shutdown of the auxiliary source provided by this utility model.

[0036] Figure 2 This is a circuit diagram of the drive circuit for the rapid shutdown auxiliary source provided by this utility model. Detailed Implementation

[0037] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0038] refer to Figure 1 , Figure 1 This invention provides a driving circuit for a fast shutdown auxiliary source. This fast shutdown auxiliary source driving circuit can be applied to LED driver power supplies, emergency power supplies, etc.

[0039] Specifically, such as Figure 1As shown, the driving circuit for the rapid shutdown of the auxiliary source includes: an EMI filter module 10, a rectification filter module 20, an intermediate processing module, an output module 80, an auxiliary source 70, and a dimming control module 90. The intermediate processing module includes: a PFC module 30, a DC-DC module 50, a PFC control module 40, and a DC-DC control module 60. The EMI filter module 10, rectification filter module 20, output module 80, dimming control module 90, PFC module 30, DC-DC module 50, PFC control module 40, and DC-DC control module 60 are commonly used modules in LED driving circuits, and their functions and principles adopt existing solutions; therefore, this invention does not impose specific limitations on them.

[0040] In this embodiment of the present invention, the EMI filter module 10, the rectifier filter module 20, the intermediate processing module and the output module 80 are connected in sequence, and the auxiliary source 70 is connected to the intermediate processing module and the dimming control module 90 respectively. The power supply input terminal of the auxiliary source 70 is located between the output terminal of the rectifier filter module 20 and the input terminal of the intermediate processing module.

[0041] Specifically, the EMI filter module 10 is used to connect to an external power supply, to receive AC signals and to perform EMI filtering on the AC signals; the rectifier filter module 20 is used to rectify and filter the AC signals and then provide input signals and power supply signals to the intermediate processing module and the auxiliary source 70 respectively; the auxiliary source 70 is used to provide power to the intermediate processing module and the dimming control module 90 during normal operation, and to quickly shut down when the AC signal is cut off.

[0042] In this embodiment of the utility model, by directly connecting the power supply terminal of the auxiliary source 70 to the output terminal of the rectifier filter module 20 (i.e., the rectifier bridge), the control chip of the auxiliary source 70 can be quickly shut down when the input AC signal is de-energized, thus meeting the requirement that the emergency system can be quickly started by being powered by the battery.

[0043] Optionally, in this embodiment of the present invention, the auxiliary source 70 includes: an input module, a linear voltage regulator module, a stable power supply module, an isolation module, and a control chip.

[0044] The input terminal of the input module is connected to the output terminal of the rectifier and filter module 20. The first output terminal of the input module is connected to the power supply terminal of the control chip. The second output terminal of the input module is connected to the drive terminal of the linear regulator module. The input terminal of the linear regulator module is connected to the stable power supply module. The output terminal of the linear regulator module is connected to the input terminal of the isolation module. The output terminal of the isolation module is connected to the power supply terminal of the control chip.

[0045] The input module is used to process the voltage provided by the output terminal of the rectifier and filter module 20 and provide the start-up voltage to the control chip, and to provide the drive signal to the linear regulator module after the control chip starts working, and to quickly stop outputting the drive signal when the AC signal is cut off; the linear regulator module is used to provide the working voltage to the control chip through the isolation module after the driving signal is turned on and the working signal provided by the stable power supply module is regulated, and to cut off the working signal according to the control of the input module when the AC signal is cut off.

[0046] Optionally, in this embodiment of the present invention, the input module includes: a current limiting circuit, a clamping circuit, and a filtering circuit.

[0047] The input terminal of the current limiting circuit is connected to the output terminal of the rectifier and filter module 20, the first output terminal of the current limiting circuit is connected to the input terminal of the clamping circuit, and the second output terminal of the current limiting circuit is connected to the control terminal of the linear regulator module; the output terminal of the clamping circuit is connected to the filter circuit and then to the power supply terminal of the control chip.

[0048] The principle of the drive circuit for the fast shutdown auxiliary source of this utility model will be explained below with a specific embodiment.

[0049] Specifically, such as Figure 2 As shown, in a preferred embodiment, the current limiting circuit includes: a tenth resistor R10, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a second resistor R2. The control chip U1 is the control IC in the auxiliary source 70 circuit of the LED driver power supply, and its function and principle adopt existing solutions. For example, the OB25133JPSOP-7 chip can be used.

[0050] The tenth resistor R10, the sixth resistor R6, the seventh resistor R7, the eighth resistor R8, and the second resistor R2 are connected in series between the output terminal of the rectifier filter module 20 and the control terminal of the linear regulator module. The connection node between the eighth resistor R8 and the second resistor R2 is the first output terminal of the current limiting circuit, and the connection node between the second resistor R2 and the control terminal of the linear regulator module is the second output terminal of the current limiting circuit.

[0051] like Figure 2 As shown, in this embodiment, the clamping circuit includes: a first Zener diode ZD501; the cathode of the first Zener diode ZD501 is the input terminal of the clamping circuit, and the anode of the first Zener diode ZD501 is the output terminal of the clamping circuit.

[0052] like Figure 2 As shown, in this embodiment, the filtering circuit includes: a first filtering capacitor C511; the first end of the first filtering capacitor C511 is connected to the anode of the first Zener diode ZD501 and connected to the power supply terminal of the control chip U1, and the second end of the first filtering capacitor C511 is grounded.

[0053] like Figure 2 As shown, in this embodiment, the linear voltage regulator module includes: a first resistor R1, a second Zener diode ZD502, a second filter capacitor C505, and a transistor Q502. The first terminal of the first resistor R1 is connected to the base of the transistor Q502, the second terminal of the first resistor R1 is connected to the second output terminal of the input module, the cathode of the second Zener diode ZD502 is connected to the second terminal of the first resistor R1, and the anode of the second Zener diode ZD502 is grounded; the collector of the transistor Q502 is connected to the stable power supply module, and the emitter of the transistor Q502 is connected to the isolation module. The voltage after passing through the tenth resistor R10, the seventh resistor R7, the eighth resistor R8, and the second resistor R2 (i.e., Figure 2 The base voltage (VM) of transistor Q502 is provided by the transistor. The first resistor R1 connected to the base of transistor Q502 is a current-limiting resistor. Since the base current is extremely small, the voltage generated across the first resistor R1 is extremely small. Therefore, the base voltage is approximately equal to the voltage of the second Zener diode ZD502.

[0054] like Figure 2 As shown, in this embodiment, the stable power supply module includes: a transformer T1-A, a second diode D503, and a third capacitor C3. The first terminal of the transformer T1-A is connected to the anode of the second diode D503, the second terminal of the transformer T1-A is grounded, the cathode of the second diode D503 is connected to the collector of the transistor Q502 and the first terminal of the third capacitor C3, and the second terminal of the third capacitor C3 is grounded.

[0055] like Figure 2 As shown, in this embodiment, the isolation module includes: a first diode D501; the anode of the first diode D501 is connected to the emitter of the transistor Q502, and the cathode of the first diode D501 is connected to the first output terminal of the input module.

[0056] like Figure 2 As shown, the auxiliary power source 70 is a flyback circuit, where HV+ is the voltage boosted by the PFC module 30. Because the PFC module 30 uses a large-capacity capacitor for energy storage, its voltage drops to zero much more slowly than that of the rectifier bridge. Therefore, in existing solutions, the presence of this large-capacity capacitor prevents the auxiliary power source 70 from shutting off quickly when AC power fails. Based on this, this invention moves the power supply of the auxiliary power source 70 to the front end of the PFC module 30, i.e., the output terminal of the rectifier filter module 20. Since the capacitor at the output terminal of the rectifier filter module 20 is a small-capacity capacitor, it can quickly drop to zero when AC power fails. Therefore, the power supply of the auxiliary power source 70 is reduced to zero, thus achieving the goal of quickly shutting off the auxiliary power source 70.

[0057] like Figure 2As shown, VAC is the voltage output by the rectifier and filter module 20. The specific working principle of this auxiliary source 70 is as follows:

[0058] How it works during startup:

[0059] When the power supply is turned on, the AC signal is input to the rectifier and filter module 20. After rectification and filtering by the rectifier and filter module 20, a VAC signal is output. This VAC signal passes sequentially through the tenth resistor R10, the sixth resistor R6, the seventh resistor R7, and the eighth resistor R8 before being sent to the first Zener diode ZD501. When the VAC signal reaches the breakdown voltage of the first Zener diode ZD501, the first Zener diode ZD501 conducts, thereby transmitting the voltage to the first filter capacitor C511. During this process, the voltage of the first filter capacitor C511 gradually increases. When the voltage rises to reach the operating voltage of the control chip U1, the control chip U1 turns on. When the voltage of the VAC signal is lower than the breakdown voltage of the first Zener diode ZD501, the first Zener diode ZD501 does not conduct, and the control chip U1 does not operate, thus achieving the undervoltage protection function.

[0060] How it works after startup:

[0061] After the control chip U1 is started, the transformer T1-A, the second diode D503, and the third capacitor C3 form another output section of the auxiliary source 70. The output voltage is regulated by a linear voltage regulator module, and the regulated voltage supplies power to the control chip U1 through the first diode D501 (at this time, the power supply is stable). The first diode D501 serves an isolation function, that is, it prevents the voltage generated at the first filter capacitor C511 from being separated from the voltage output by the transformer T1-A, the second diode D503, and the third capacitor C3, and the voltage regulated by the linear voltage regulator module.

[0062] like Figure 2 As shown, since the VAC source is after the rectifier bridge and before the PFC module 30, and the capacitors here (i.e., after the rectifier bridge and before the PFC module 30) are small-capacity capacitors with fast discharge characteristics, when the power supply is suddenly interrupted (i.e., the AC signal is lost), the voltage at the first filter capacitor C511 will quickly drop to zero due to the rapid discharge of the capacitors after the rectifier bridge, and will no longer supply power to the control chip U1; at the same time, VM will also drop to zero quickly, the base voltage of transistor Q502 will drop to zero, and transistor Q502 will be cut off, thereby quickly cutting off the power supply to the control chip U1, and the control chip U1 will stop working, that is, the auxiliary source 70 can be quickly turned off.

[0063] This utility model also provides an emergency power supply, which includes: the drive circuit for quickly shutting off the auxiliary source disclosed in this utility model.

[0064] This invention enables the auxiliary power source 70 to be quickly shut off when AC power fails, effectively preventing the auxiliary power source 70 from continuously supplying power due to the large electrolytic capacitor, thus failing to meet the needs of rapid switching and allowing the emergency power supply to be quickly switched and restarted.

[0065] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They do not limit the scope of protection of this utility model. All equivalent changes and modifications made within the scope of the claims of this utility model should fall within the scope of the claims of this utility model.

Claims

1. A drive circuit for quickly shutting off an auxiliary source, characterized in that, include: EMI filter module, rectifier filter module, intermediate processing module, output module, auxiliary source and dimming control module; The EMI filter module, the rectifier filter module, the intermediate processing module, and the output module are connected in sequence. The auxiliary source is connected to the intermediate processing module and the dimming control module respectively, and the power supply input terminal of the auxiliary source is located between the output terminal of the rectifier filter module and the input terminal of the intermediate processing module. The EMI filtering module is used to connect to an external power supply, to receive AC signals, and to perform EMI filtering on the AC signals. The rectification and filtering module is used to rectify and filter the AC signal and then provide input signals and power supply signals to the intermediate processing module and the auxiliary source, respectively. The auxiliary source is used to provide power to the intermediate processing module and the dimming control module during normal operation, and to quickly shut down when the AC signal is cut off.

2. The drive circuit for quickly shutting off the auxiliary source according to claim 1, characterized in that, The auxiliary source includes: an input module, a linear voltage regulator module, a stable power supply module, an isolation module, and a control chip; The input terminal of the input module is connected to the output terminal of the rectifier and filter module, the first output terminal of the input module is connected to the power supply terminal of the control chip, the second output terminal of the input module is connected to the drive terminal of the linear regulator module, the input terminal of the linear regulator module is connected to the stable power supply module, the output terminal of the linear regulator module is connected to the input terminal of the isolation module, and the output terminal of the isolation module is connected to the power supply terminal of the control chip. The input module is used to process the voltage provided by the output terminal of the rectifier and filter module, provide a start-up voltage to the control chip, and provide a drive signal to the linear regulator module after the control chip starts working, and quickly stop outputting the drive signal when the AC signal is cut off; The linear voltage regulator module is used to provide the operating voltage to the control chip through the isolation module after the driving signal is turned on and the operating signal provided by the stable power supply module is regulated, and to cut off the operating signal according to the control of the input module when the AC signal is cut off.

3. The driving circuit for rapidly shutting off the auxiliary source according to claim 2, characterized in that, The input module includes: a current limiting circuit, a clamping circuit, and a filtering circuit; The input terminal of the current limiting circuit is connected to the output terminal of the rectifier and filter module, the first output terminal of the current limiting circuit is connected to the input terminal of the clamping circuit, and the second output terminal of the current limiting circuit is connected to the control terminal of the linear regulator module. The output of the clamping circuit is connected to the filter circuit and then to the power supply of the control chip.

4. The drive circuit for quickly shutting off the auxiliary source according to claim 3, characterized in that, The current limiting circuit includes: a tenth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a second resistor; The tenth resistor, the sixth resistor, the seventh resistor, the eighth resistor, and the second resistor are connected in series between the output terminal of the rectifier filter module and the control terminal of the linear regulator module. The connection node between the eighth resistor and the second resistor is the first output terminal of the current limiting circuit, and the connection node between the second resistor and the control terminal of the linear voltage regulator module is the second output terminal of the current limiting circuit.

5. The drive circuit for quickly shutting off the auxiliary source according to claim 4, characterized in that, The clamping circuit includes: a first Zener diode; The cathode of the first Zener diode is the input terminal of the clamping circuit, and the anode of the first Zener diode is the output terminal of the clamping circuit.

6. The drive circuit for quickly shutting off the auxiliary source according to claim 5, characterized in that, The filtering circuit includes: a first filtering capacitor; The first end of the first filter capacitor is connected to the anode of the first Zener diode and to the power supply terminal of the control chip, and the second end of the first filter capacitor is grounded.

7. The drive circuit for quickly shutting off the auxiliary source according to claim 2, characterized in that, The linear voltage regulator module includes: a first resistor, a second Zener diode, a second filter capacitor, and a transistor; The first end of the first resistor is connected to the base of the transistor, the second end of the first resistor is connected to the second output terminal of the input module, the cathode of the second Zener diode is connected to the second end of the first resistor, and the anode of the second Zener diode is grounded. The collector of the transistor is connected to the stable power supply module, and the emitter of the transistor is connected to the isolation module.

8. The drive circuit for quickly shutting off the auxiliary source according to claim 7, characterized in that, The stable power supply module includes: a transformer, a second diode, and a third capacitor; The first terminal of the transformer is connected to the anode of the second diode, the second terminal of the transformer is grounded, the cathode of the second diode is connected to the collector of the transistor and the first terminal of the third capacitor, and the second terminal of the third capacitor is grounded.

9. The drive circuit for quickly shutting off the auxiliary source according to claim 8, characterized in that, The isolation module includes: a first diode; The anode of the first diode is connected to the emitter of the transistor, and the cathode of the first diode is connected to the first output terminal of the input module.

10. An emergency power supply, characterized in that, include: The drive circuit for rapidly shutting off the auxiliary source as described in any one of claims 1-9.

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