Single-live-wire electricity-taking circuit and intelligent switch
By using an isolation transformer module and a synchronous rectification module in a single-fire power supply circuit, the circuit structure is simplified, the layout difficulty problem caused by the complexity of the circuit in the existing technology is solved, and the circuit is simplified and the layout is reduced.
Patent Information
- Application Number
- CN202422029167.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-20
- Publication Date
- 2025-09-09
- Estimated Expiration
- 2034-08-20
AI Technical Summary
The existing single-fire power supply circuit requires the use of more circuit components in the non-isolated power supply part, resulting in complex circuits and increasing the difficulty of layout in smart switch products.
An isolation transformer module and a synchronous rectifier module are used to obtain voltage from the live wire through a high-frequency transformer and output the power supply voltage through an auxiliary winding, simplifying the circuit structure and reducing layout difficulty.
The circuit complexity of simultaneously isolating and non-isolating power from the live wire is reduced, simplifying the layout difficulty of the smart switch product.
Smart Images
Figure CN223321988U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of intelligent switches, and in particular to a single-fire power supply circuit and an intelligent switch. Background Art
[0002] Smart switch products typically draw power from the live wire. This circuit is called a single-live power circuit. This circuit divides power into two power paths: an isolated power supply, electrically isolated from the live wire, that powers functional modules that come into contact with the human body, and a non-isolated power supply, which is not electrically isolated from the live wire.
[0003] The auxiliary winding of the high-frequency transformer of existing intelligent switch products is usually used to power the switch control unit. The existing single-fire power supply circuit is relatively complex because the circuit of the non-isolated power supply part requires the use of more circuit components, which makes the layout of the single-fire power supply circuit on the product more difficult. Utility Model Content
[0004] In view of this, the present application provides a single-fire power supply circuit and an intelligent switch, which are used to reduce the complexity of the single-fire power supply circuit and thereby reduce the difficulty of layout of the single-fire power supply circuit in the intelligent switch. The technical solution of the present application is as follows:
[0005] The first aspect of the present application provides a single-fire power supply circuit, including: an isolation transformer module, the isolation transformer module includes a high-frequency transformer and a switch control unit, the switch control unit is connected to the main winding and auxiliary winding of the high-frequency transformer; the isolation transformer module is used to receive the alternating current of the live wire, and the switch control unit controls the high-frequency transformer to convert the alternating current into a target alternating current voltage and output it in isolation. The auxiliary winding of the high-frequency transformer is also used to output a power supply voltage to a load connected to it, and the switch control unit receives the power supply voltage to work; a synchronous rectifier module, connected to the isolation transformer module, is used to convert the target AC voltage into a first power supply voltage and then output it.
[0006] In one embodiment of the present application, the single-fire power supply circuit also includes: a DC step-down module, which is connected to the auxiliary winding of the high-frequency transformer, used to receive the supply voltage of the auxiliary winding, adjust the supply voltage to a second supply voltage of a preset voltage value, and then output it.
[0007] In one embodiment of the present application, the isolation transformer module also includes: a rectifier bridge unit and a filter unit, the rectifier bridge unit is connected to the filter unit, and the filter unit is connected to the high-frequency transformer; the rectifier bridge unit is used to receive the alternating current and convert the alternating current into primary direct current; the filter unit is used to smooth and filter the primary direct current and then output it to the high-frequency transformer; the switch control unit is used to control the high-frequency transformer to convert the primary direct current after smoothing and filtering into the target alternating voltage of a preset frequency and output it in isolation.
[0008] In one embodiment of the present application, the single-fire power supply circuit also includes: a zero-crossing detection module, used to receive the second supply voltage, and obtain the zero-crossing detection signal of the live line based on the second voltage; a control module, used to receive the zero-crossing detection signal, and obtain the zero-crossing detection result of the live line based on the zero-crossing detection signal.
[0009] In one embodiment of the present application, the filtering unit includes an inductor, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a third capacitor and a fifth diode; the first end of the inductor is connected to the rectifier bridge unit, and the second end of the inductor is connected to the first end of the main winding; the first resistor is connected to the inductor in parallel; the first end of the first capacitor is connected to the second end of the inductor, and the second end of the first capacitor is grounded; the first end of the second capacitor is connected to the second end of the inductor, and the second end of the second capacitor is grounded; the first end of the second resistor is connected to the second end of the inductor, and the second end of the resistor is connected to the negative electrode of the fifth diode through the third resistor; the positive electrode of the fifth diode is connected to the second end of the main winding; the third capacitor is connected to the second resistor in parallel.
[0010] In one embodiment of the present application, the switch control unit includes a fourth resistor, a fifth resistor, a sixth resistor, a fourth capacitor, a fifth capacitor, a sixth diode and a switch chip; the first end of the fourth resistor is connected to the rectifier bridge unit, and the second end of the resistor is connected to the power supply end of the switch chip through the fifth resistor; the first end of the fourth capacitor is connected to the power supply end of the switch chip, and the second end of the fourth capacitor is grounded; the positive electrode of the sixth diode is connected to the auxiliary winding through the sixth resistor; the negative electrode of the sixth diode is connected to the first end of the fourth capacitor; and the fifth capacitor is connected in parallel with the fourth capacitor.
[0011] In one embodiment of the present application, the isolation transformer module also includes an isolation sampling unit, which is connected to the output end of the synchronous rectification module and the feedback end of the switch control unit; the isolation sampling unit is used to collect the voltage value of the first supply voltage and transmit the voltage value to the feedback end of the switch control unit after electrical isolation; the switch control unit is also used to adjust the operating frequency of the high-frequency transformer according to the voltage value.
[0012] In one embodiment of the present application, the isolation sampling unit includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a sixth capacitor, a seventh capacitor, and an optoelectronic isolator; a first end of the seventh resistor is connected to the output end of the synchronous rectification module, and a second end of the seventh resistor is connected to the positive electrode of the optoelectronic isolator; a first end of the eighth resistor is connected to the first end of the seventh resistor, and a second end of the eighth resistor is grounded through the thirteenth resistor; a first end of the ninth resistor is connected to the positive electrode of the optoelectronic isolator, and a second end of the ninth resistor is connected to the negative electrode of the optoelectronic isolator; a first end of the tenth resistor is connected to the negative electrode of the optoelectronic isolator, and a second end of the tenth resistor is connected to the second end of the eighth resistor through the sixth capacitor; a first end of the eleventh resistor is connected to the feedback end of the switch control unit, and a second end of the eleventh resistor is connected to the collector of the optoelectronic isolator; a first end of the twelfth resistor is connected to the first end of the thirteenth resistor, and a second end of the twelfth resistor is grounded; a first end of the seventh capacitor is connected to the first end of the eleventh resistor, and a second end of the seventh capacitor is grounded.
[0013] In one embodiment of the present application, the rectifier bridge unit includes a first diode, a second diode, a third diode and a fourth diode; the positive pole of the first diode is connected to the live wire, and the negative pole of the first diode is connected to the filtering unit; the negative pole of the second diode is connected to the filtering unit, and the positive pole of the second diode is connected to the neutral wire; the negative pole of the third diode is connected to the neutral wire, and the positive pole of the third diode is grounded; the positive pole of the fourth diode is grounded, and the negative pole of the fourth diode is connected to the live wire.
[0014] The present application also provides a single-fire power supply circuit, including: a first diode, a second diode, a third diode, a fourth diode, an inductor, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a third capacitor, a fifth diode, a fourth resistor, a fifth resistor, a sixth resistor, a fourth capacitor, a fifth capacitor, a sixth diode, a switch chip, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a sixth capacitor, a seventh capacitor, an optoelectronic isolator, a high-frequency transformer, and a synchronous rectifier chip; the positive electrode of the first diode is connected to the live wire, the negative electrode of the first diode is connected to the first end of the inductor; the negative electrode of the second diode is connected to the first end of the inductor, and the second The positive electrode of the diode is connected to the neutral line; the negative electrode of the third diode is connected to the neutral line, and the positive electrode of the third diode is grounded; the positive electrode of the fourth diode is grounded, and the negative electrode of the fourth diode is connected to the live wire; the second end of the inductor is connected to the first end of the main winding of the high-frequency transformer; the first resistor is connected in parallel with the inductor; the first end of the first capacitor is connected to the second end of the inductor, and the second end of the first capacitor is grounded; the first end of the second capacitor is connected to the second end of the inductor, and the second end of the second capacitor is grounded; the first end of the second resistor is connected to the second end of the inductor, and the second end of the resistor is connected to the negative electrode of the fifth diode through the third resistor; the positive electrode of the fifth diode is connected to the first end of the main winding The second end; the third capacitor is connected in parallel with the second resistor; the first end of the fourth resistor is connected to the cathode of the first diode, and the second end of the fourth resistor is connected to the power supply end of the switch chip through the fifth resistor; the first end of the fourth capacitor is connected to the power supply end of the switch chip, and the second end of the fourth capacitor is grounded; the fifth capacitor is connected in parallel with the fourth capacitor; the anode of the sixth diode is connected to the auxiliary winding of the high-frequency transformer through the sixth resistor; the cathode of the sixth diode is connected to the first end of the fourth capacitor; the output end of the high-frequency transformer is connected to the input end of the synchronous rectifier chip; the first end of the seventh resistor is connected to the output end of the synchronous rectifier chip, and the second end of the seventh resistor is connected to connected to the positive electrode of the photoelectric isolator; the first end of the eighth resistor is connected to the first end of the seventh resistor, and the second end of the eighth resistor is grounded through the thirteenth resistor; the first end of the ninth resistor is connected to the positive electrode of the photoelectric isolator, and the second end of the ninth resistor is connected to the negative electrode of the photoelectric isolator; the first end of the tenth resistor is connected to the negative electrode of the photoelectric isolator, and the second end of the tenth resistor is connected to the second end of the eighth resistor through the sixth capacitor; the first end of the eleventh resistor is connected to the feedback end of the switch chip, and the second end of the eleventh resistor is connected to the collector of the photoelectric isolator; the first end of the twelfth resistor is connected to the first end of the thirteenth resistor, and the second end of the twelfth resistor is grounded;The first end of the seventh capacitor is connected to the first end of the eleventh resistor, and the second end of the seventh capacitor is grounded.
[0015] The present application also provides an intelligent switch, comprising the single-fire power supply circuit.
[0016] The single-fire power supply circuit in the embodiment of the present application includes an isolation transformer module, which includes a high-frequency transformer. By outputting the target current to the synchronous rectifier module through the high-frequency transformer, the effect of isolating and obtaining voltage from the live wire through the high-frequency transformer can be achieved. The first power supply voltage output by the synchronous rectifier module is output to the lower-level circuit that needs to be isolated from the live wire to power it. At the same time, the power supply voltage is output through the auxiliary winding of the high-frequency transformer, which can achieve the effect of non-isolated acquisition of power supply voltage from the live wire through the auxiliary winding of the high-frequency transformer. In addition to powering the switch control unit, the output power supply voltage can also be separated into circuits for use by other loads, thereby reducing the complexity of the circuit for simultaneously isolating and non-isolating power supply from the live wire, thereby reducing the layout difficulty of the single-fire power supply circuit in the smart switch product. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 This is a schematic block diagram of a single-fire power supply circuit provided in an embodiment of the present application.
[0018] Figure 2 This is a schematic block diagram of another single-fire power supply circuit provided in an embodiment of the present application.
[0019] Figure 3 This is a schematic block diagram of an isolation transformer module provided in an embodiment of the present application.
[0020] Figure 4 This is a schematic block diagram of another isolation transformer module provided in an embodiment of the present application.
[0021] Figure 5 This is a circuit diagram of a single-fire power supply circuit provided in an embodiment of the present application. DETAILED DESCRIPTION
[0022] It should be noted that, in the embodiments of the present application, "at least one" refers to one or more, and "more than one" refers to two or more than two. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The terms "first", "second", "third", "fourth", etc. (if any) in the specification, claims and drawings of this application are used to distinguish similar objects, rather than to describe a specific order or sequence.
[0023] It should also be noted that the method disclosed in the embodiments of the present application or the method shown in the flowchart includes one or more steps for implementing the method. Without departing from the scope of the claims, the execution order of multiple steps can be interchanged with each other, and some steps can also be deleted.
[0024] Smart switch products typically draw power from the live wire. This circuit is called a single-live power circuit. This circuit divides power into two power paths: an isolated power supply, electrically isolated from the live wire, that powers functional modules that come into contact with the human body, and a non-isolated power supply, which is not electrically isolated from the live wire.
[0025] The existing single-fire power supply circuit is relatively complex because the circuit of the non-isolated power supply part requires the use of more circuit components, which makes the layout of the single-fire power supply circuit on the product more difficult.
[0026] The present application provides a single-fire power supply circuit and an intelligent switch, which are used to reduce the complexity of the single-fire power supply circuit and thereby reduce the difficulty of layout of the single-fire power supply circuit in the intelligent switch.
[0027] Please refer to Figure 1 , Figure 1 This is a schematic block diagram of a single-fire power supply circuit provided in an embodiment of the present application, wherein the single-fire power supply circuit 100a includes: an isolation transformer module 110, a synchronous rectification module 120 and a DC step-down module 130.
[0028] In an embodiment of the present application, the isolation transformer module 110 includes a high-frequency transformer 111 and a switch control unit 112, wherein the switch control unit 112 is connected to the main winding and auxiliary winding of the high-frequency transformer 111. The isolation transformer module 110 is used to receive the AC power from the live wire, and control the high-frequency transformer 111 through the switch control unit 112 to convert the AC power into the target AC voltage and output it in isolation. The auxiliary winding of the high-frequency transformer 111 is also used to output a supply voltage to the load connected to it, and the switch control unit 112 receives the supply voltage to operate. The synchronous rectifier module 120 is connected to the isolation transformer module 110 and is used to convert the target AC voltage into a first supply voltage and output it.
[0029] It can be understood that the single-fire power supply circuit 100a of the embodiment of the present application includes an isolation transformer module 110, and the isolation transformer module 110 includes a high-frequency transformer 111. The target current is output to the synchronous rectifier module 120 through the high-frequency transformer 111, so that the effect of isolating and obtaining voltage from the live wire through the high-frequency transformer 111 can be achieved. The first power supply voltage output by the synchronous rectifier module 120 is output to the lower-level circuit that needs to be isolated from the live wire to power it. At the same time, the power supply voltage is output through the auxiliary winding of the high-frequency transformer 111, so that the effect of non-isolated acquisition of power supply voltage from the live wire through the auxiliary winding of the high-frequency transformer 111 can be achieved. In addition to supplying power to the switch control unit 112, the output power supply voltage can also be separated out for use by other loads, thereby reducing the complexity of the circuit for isolating and non-isolating power supply from the live wire at the same time, thereby reducing the layout difficulty of the single-fire power supply circuit in the smart switch product. Please refer to Figure 2 , Figure 2 This is a schematic block diagram of another single-fire power supply circuit provided in an embodiment of the present application. Compared with the above-mentioned single-fire power supply circuit 100a, the single-fire power supply circuit 100b further includes:
[0030] The DC step-down module 130 is connected to the auxiliary winding of the high-frequency transformer 111 , and is used to receive the supply voltage of the auxiliary winding, adjust the supply voltage to a second supply voltage of a preset voltage value, and then output it.
[0031] It can be understood that by setting up a DC step-down module 130 to receive the power supply voltage from the auxiliary winding of the high-frequency transformer 111, the effect of obtaining the power supply voltage from the live wire in a non-isolated manner through the auxiliary winding of the high-frequency transformer 111 can be achieved, and then the power supply voltage is adjusted to a second power supply voltage of a preset voltage value and output to a lower-level circuit that does not need to be isolated from the live wire to power the lower-level circuit, thereby reducing the complexity of the circuit for simultaneously isolating and non-isolating power supply from the live wire, thereby reducing the layout difficulty of the single-fire power supply circuit 100.
[0032] The zero-crossing detection module 140 is configured to receive the second supply voltage and obtain a zero-crossing detection signal of the live wire according to the second voltage. The control module 150 is configured to receive the zero-crossing detection signal and obtain a zero-crossing detection result of the live wire according to the zero-crossing detection signal.
[0033] It can be understood that the above-mentioned single-fire power supply circuit 100 can be applied to the intelligent switch, so as to take power from the live wire and transmit the voltage isolated from the live wire and the voltage not isolated from the live wire to the functional modules or circuits required by the intelligent switch. For example, the first power supply voltage isolated from the live wire output by the synchronous rectifier module 120 can be output to the screen of the intelligent switch to power the screen of the intelligent switch to avoid electric shock when the screen comes into contact with the human body. The second power supply voltage output by the DC step-down module 130 can be output to various circuits for detecting the live wire of the intelligent switch, for example, it can be output to the zero-crossing detection module 140 of the intelligent switch. The zero-crossing detection module 140 obtains the zero-crossing detection signal of the live wire based on the second power supply voltage, and then transmits the zero-crossing detection signal to the control module 150 of the intelligent switch to obtain the zero-crossing detection result of the live wire through the control module 150.
[0034] Please refer to Figure 3 , Figure 3 This is a schematic block diagram of an isolation transformer module provided in an embodiment of the present application, wherein the isolation transformer module 110a further includes a rectifier bridge unit 113 and a filter unit 114 .
[0035] In the embodiment of the present application, the rectifier bridge unit 113 is connected to the filter unit 114, which is connected to the high-frequency transformer 111. The switch control unit 112 is connected to the main winding and auxiliary winding of the high-frequency transformer. The rectifier bridge unit 113 is used to receive alternating current (AC) and convert it into primary direct current (DC). The filter unit 114 is used to smooth and filter the primary DC before outputting it to the high-frequency transformer. The switch control unit 112 is used to receive a power supply voltage and control the high-frequency transformer to convert the smoothed and filtered primary DC into a target AC voltage of a preset frequency and output it in isolation.
[0036] In some embodiments, as Figure 4 Compared to the aforementioned isolation transformer module 110a, the illustrated isolation transformer module 110b further includes an isolation sampling unit 115, which is connected to the output of the synchronous rectification module and the feedback terminal of the switch control unit 112. The isolation sampling unit 115 is configured to collect the voltage value of the first supply voltage and transmit the voltage value to the feedback terminal of the switch control unit 112 after electrical isolation. The switch control unit 112 is also configured to adjust the operating frequency of the high-frequency transformer based on the voltage value.
[0037] Please refer to Figure 5 , Figure 5A circuit diagram of a single-fire power supply circuit provided in an embodiment of the present application, wherein the single-fire power supply circuit 100 includes the isolation transformer module 110, the synchronous rectification module 120, the DC step-down module 130 and the zero-crossing detection module 140 in the above-mentioned embodiment, and the isolation transformer module 110 includes a rectifier bridge unit 113, a filtering unit 114, a switch control unit 112 and an isolation sampling unit 115.
[0038] In the embodiment of the present application, the rectifier bridge unit 113 includes a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4. The anode of the first diode D1 is connected to the live line L, and the cathode of the first diode D1 is connected to the filter unit 114. The cathode of the second diode D2 is connected to the filter unit 114, and the anode of the second diode D2 is connected to the neutral line. The cathode of the third diode D3 is connected to the neutral line N, and the anode of the third diode D3 is grounded. The anode of the fourth diode D4 is grounded, and the cathode of the fourth diode D4 is connected to the live line L.
[0039] The filtering unit 114 includes an inductor L1, a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, a second capacitor C2, a third capacitor C3, and a fifth diode D5. The first end of the inductor L1 is connected to the rectifier bridge unit 113, that is, to the cathode of the first diode D1. The second end of the inductor L1 is connected to the first end of the main winding of the high-frequency transformer 111. The first resistor R1 is connected in parallel with the inductor L1. The first end of the first capacitor C1 is connected to the second end of the inductor L1, and the second end of the first capacitor C1 is grounded. The first end of the second capacitor C2 is connected to the second end of the inductor L1, and the second end of the second capacitor C2 is grounded. The first end of the second resistor R2 is connected to the second end of the inductor L1, and the second end of the resistor is connected to the cathode of the fifth diode D5 through the third resistor R3. The anode of the fifth diode D5 is connected to the second end of the main winding. The third capacitor C3 is connected in parallel with the second resistor R2.
[0040] The switch control unit 112 includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a fourth capacitor C4, a fifth capacitor C5, a sixth diode D6, and a switch chip U1. The first end of the fourth resistor R4 is connected to the rectifier bridge unit 113, and the second end of the resistor is connected to the power supply terminal VDD of the switch chip U1 through the fifth resistor R5. The first end of the fourth capacitor C4 is connected to the power supply terminal VDD of the switch chip U1, and the second end of the fourth capacitor C4 is grounded. The anode of the sixth diode D6 is connected to the auxiliary winding through the sixth resistor R6. The cathode of the sixth diode D6 is connected to the first end of the fourth capacitor C4. The fifth capacitor C5 is connected in parallel with the fourth capacitor C4. The switch control unit 112 also includes a seventh diode D7, the cathode of the seventh diode D7 is connected to the fifth resistor R5, and the anode of the seventh diode D7 is connected to the anode of the sixth diode D6. The cathode of the sixth diode D6 outputs the second supply voltage.
[0041] The isolated sampling unit 115 includes a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a sixth capacitor C6, a seventh capacitor C7, and an optoelectronic isolator U2. A first end of the seventh resistor R7 is connected to the output terminal of the synchronous rectifier module, and a second end of the seventh resistor R7 is connected to the positive electrode of the optoelectronic isolator U2. A first end of the eighth resistor R8 is connected to the first end of the seventh resistor R7, and a second end of the eighth resistor R8 is connected to ground via the thirteenth resistor R13. A first end of the ninth resistor R9 is connected to the positive electrode of the optoelectronic isolator U2, and a second end of the ninth resistor R9 is connected to the negative electrode of the optoelectronic isolator U2. A first end of the tenth resistor R10 is connected to the negative electrode of the optoelectronic isolator U2, and a second end of the tenth resistor R10 is connected to the second end of the eighth resistor R8 via the sixth capacitor C6. A first end of the eleventh resistor R11 is connected to the feedback terminal of the switch control unit 112, and a second end of the eleventh resistor R11 is connected to the collector of the optoelectronic isolator U2. The first end of the twelfth resistor R12 is connected to the first end of the thirteenth resistor R13, and the second end of the twelfth resistor R12 is grounded. The first end of the seventh capacitor C7 is connected to the first end of the eleventh resistor R11, and the second end of the seventh capacitor C7 is grounded. The synchronous rectification module 120 includes a synchronous rectification chip U3, a fourteenth resistor R14, an eighth capacitor C8, a ninth capacitor C9, and a tenth capacitor C10.
[0042] The zero-crossing detection module 140 includes an AC zero-crossing sampling unit 141, a zero-crossing detection chip 142, a fourteenth resistor R14, an eighth diode D8, an optoelectronic isolator U3, and an indicator LED. The first pin 1 of the optoelectronic isolator U3 is used to receive a power supply voltage, the second pin 2 of the optoelectronic isolator U3 is grounded via the indicator LED, the third pin 3 of the optoelectronic isolator U3 is connected to the zero-crossing detection chip 142, the third pin 3 of the optoelectronic isolator U3 is connected to the fourth pin 4 via the eighth diode D8, and the fourth pin 4 of the optoelectronic isolator U3 is connected to the DC step-down module 130 via the fourteenth resistor R14. The AC zero-crossing sampling unit 141 also receives a power supply voltage.
[0043] An embodiment of the present application also provides an intelligent switch, including the single-fire power supply circuit of any of the above embodiments. It can be understood that the beneficial effects of the intelligent switch can refer to the beneficial effects of the single-fire power supply circuit in the above embodiments, and will not be repeated here.
[0044] The embodiments described above are merely preferred embodiments of the present application and are not intended to limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements made to the technical solutions of the present application by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present application.
Claims
1. A single-fire power supply circuit, characterized in that: include: An isolation transformer module, comprising a high-frequency transformer and a switch control unit, wherein the switch control unit is connected to a main winding and an auxiliary winding of the high-frequency transformer; The isolation transformer module is used to receive the AC power of the live wire, and the switch control unit controls the high-frequency transformer to convert the AC power into a target AC voltage and output it in isolation. The auxiliary winding of the high-frequency transformer is also used to output a supply voltage to the load connected to it, and the switch control unit receives the supply voltage to operate; The synchronous rectification module is connected to the isolation transformer module and is used for converting the target AC voltage into a first power supply voltage for output.
2. The single-fire power supply circuit according to claim 1, characterized in that: Also includes: A DC step-down module is connected to the auxiliary winding of the high-frequency transformer, and is used to receive the supply voltage of the auxiliary winding, adjust the supply voltage to a second supply voltage of a preset voltage value, and then output it.
3. The single-fire power supply circuit according to claim 1, characterized in that: The isolation transformer module further includes: a rectifier bridge unit and a filter unit, wherein the rectifier bridge unit is connected to the filter unit, and the filter unit is connected to the high-frequency transformer; The rectifier bridge unit is used to receive the AC power and convert the AC power into primary DC power; The filtering unit is used to perform smooth filtering on the primary DC power and then output it to the high-frequency transformer; The switch control unit is used to control the high-frequency transformer to convert the primary direct current after smoothing and filtering into the target alternating current voltage of a preset frequency and output it in isolation.
4. The single-fire power supply circuit according to claim 1, characterized in that: The single-fire power supply circuit further includes: a zero-crossing detection module, configured to receive the second supply voltage and obtain a zero-crossing detection signal of the live wire according to the second voltage; The control module is configured to receive the zero-crossing detection signal and obtain a zero-crossing detection result of the live wire according to the zero-crossing detection signal.
5. The single-fire power supply circuit according to claim 3, characterized in that: The filtering unit includes an inductor, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a third capacitor and a fifth diode; The first end of the inductor is connected to the rectifier bridge unit, and the second end of the inductor is connected to the first end of the main winding; the first resistor is connected to the inductor in parallel; the first end of the first capacitor is connected to the second end of the inductor, and the second end of the first capacitor is grounded; the first end of the second capacitor is connected to the second end of the inductor, and the second end of the second capacitor is grounded; the first end of the second resistor is connected to the second end of the inductor, and the second end of the resistor is connected to the cathode of the fifth diode through the third resistor; the anode of the fifth diode is connected to the second end of the main winding; the third capacitor is connected to the second resistor in parallel.
6. The single-fire power supply circuit according to claim 3, characterized in that: The switch control unit includes a fourth resistor, a fifth resistor, a sixth resistor, a fourth capacitor, a fifth capacitor, a sixth diode and a switch chip; The first end of the fourth resistor is connected to the rectifier bridge unit, and the second end of the resistor is connected to the power supply end of the switch chip through the fifth resistor; the first end of the fourth capacitor is connected to the power supply end of the switch chip, and the second end of the fourth capacitor is grounded; the positive electrode of the sixth diode is connected to the auxiliary winding through the sixth resistor; the negative electrode of the sixth diode is connected to the first end of the fourth capacitor; the fifth capacitor is connected in parallel with the fourth capacitor.
7. The single-fire power supply circuit according to claim 3, characterized in that: The isolation transformer module further includes an isolation sampling unit, which is connected to the output end of the synchronous rectification module and the feedback end of the switch control unit; The isolation sampling unit is used to collect the voltage value of the first power supply voltage and transmit the voltage value to the feedback terminal of the switch control unit after electrical isolation; The switch control unit is further used to adjust the operating frequency of the high-frequency transformer according to the voltage value; The isolation sampling unit includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a sixth capacitor, a seventh capacitor and a photoelectric isolator; The first end of the seventh resistor is connected to the output end of the synchronous rectification module, and the second end of the seventh resistor is connected to the positive electrode of the optoelectronic isolator; the first end of the eighth resistor is connected to the first end of the seventh resistor, and the second end of the eighth resistor is grounded through the thirteenth resistor; the first end of the ninth resistor is connected to the positive electrode of the optoelectronic isolator, and the second end of the ninth resistor is connected to the negative electrode of the optoelectronic isolator; the first end of the tenth resistor is connected to the negative electrode of the optoelectronic isolator, and the second end of the tenth resistor is connected to the second end of the eighth resistor through the sixth capacitor; the first end of the eleventh resistor is connected to the feedback end of the switch control unit, and the second end of the eleventh resistor is connected to the collector of the optoelectronic isolator; the first end of the twelfth resistor is connected to the first end of the thirteenth resistor, and the second end of the twelfth resistor is grounded; the first end of the seventh capacitor is connected to the first end of the eleventh resistor, and the second end of the seventh capacitor is grounded.
8. The single-fire power supply circuit according to claim 3, characterized in that: The rectifier bridge unit includes a first diode, a second diode, a third diode and a fourth diode; The positive electrode of the first diode is connected to the live wire, and the negative electrode of the first diode is connected to the filtering unit; the negative electrode of the second diode is connected to the filtering unit, and the positive electrode of the second diode is connected to the neutral wire; the negative electrode of the third diode is connected to the neutral wire, and the positive electrode of the third diode is grounded; the positive electrode of the fourth diode is grounded, and the negative electrode of the fourth diode is connected to the live wire.
9. A single-fire power supply circuit, characterized in that: include: A first diode, a second diode, a third diode, a fourth diode, an inductor, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, a third capacitor, a fifth diode, a fourth resistor, a fifth resistor, a sixth resistor, a fourth capacitor, a fifth capacitor, a sixth diode, a switch chip, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a sixth capacitor, a seventh capacitor, an optoelectronic isolator, a high-frequency transformer, and a synchronous rectifier chip; The positive electrode of the first diode is connected to the live wire, and the negative electrode of the first diode is connected to the first end of the inductor; the negative electrode of the second diode is connected to the first end of the inductor, and the positive electrode of the second diode is connected to the neutral wire; the negative electrode of the third diode is connected to the neutral wire, and the positive electrode of the third diode is grounded; the positive electrode of the fourth diode is grounded, and the negative electrode of the fourth diode is connected to the live wire; The second end of the inductor is connected to the first end of the main winding of the high-frequency transformer; the first resistor is connected to the inductor in parallel; the first end of the first capacitor is connected to the second end of the inductor, and the second end of the first capacitor is grounded; the first end of the second capacitor is connected to the second end of the inductor, and the second end of the second capacitor is grounded; the first end of the second resistor is connected to the second end of the inductor, and the second end of the resistor is connected to the cathode of the fifth diode through the third resistor; the anode of the fifth diode is connected to the second end of the main winding; the third capacitor is connected to the second resistor in parallel; A first end of the fourth resistor is connected to the cathode of the first diode, and a second end of the fourth resistor is connected to the power supply terminal of the switch chip through the fifth resistor; a first end of the fourth capacitor is connected to the power supply terminal of the switch chip, and a second end of the fourth capacitor is grounded; an anode of the sixth diode is connected to the auxiliary winding of the high-frequency transformer through the sixth resistor; a cathode of the sixth diode is connected to the first end of the fourth capacitor; and the fifth capacitor is connected in parallel with the fourth capacitor. The output end of the high-frequency transformer is connected to the input end of the synchronous rectification chip; The first end of the seventh resistor is connected to the output end of the synchronous rectifier chip, and the second end of the seventh resistor is connected to the positive electrode of the optoelectronic isolator; the first end of the eighth resistor is connected to the first end of the seventh resistor, and the second end of the eighth resistor is grounded through the thirteenth resistor; the first end of the ninth resistor is connected to the positive electrode of the optoelectronic isolator, and the second end of the ninth resistor is connected to the negative electrode of the optoelectronic isolator; the first end of the tenth resistor is connected to the negative electrode of the optoelectronic isolator, and the second end of the tenth resistor is connected to the second end of the eighth resistor through the sixth capacitor; the first end of the eleventh resistor is connected to the feedback end of the switch chip, and the second end of the eleventh resistor is connected to the collector of the optoelectronic isolator; the first end of the twelfth resistor is connected to the first end of the thirteenth resistor, and the second end of the twelfth resistor is grounded; the first end of the seventh capacitor is connected to the first end of the eleventh resistor, and the second end of the seventh capacitor is grounded.
10. An intelligent switch, characterized in that: It comprises the single-fire power supply circuit as claimed in any one of claims 1 to 9.