Multi-channel constant current output circuit based on transformer and driving power supply

Abstract

The utility model relates to a transformer-based multi-channel constant current output circuit and a driving power supply. The transformer-based multi-channel constant current output circuit comprises a half-bridge module, a blocking module and a full-bridge module, the half-bridge module comprises a driving unit and a resonance unit connected with the driving unit; the resonance unit comprises a plurality of transformers which are arranged in series; the driving unit drives the resonance unit according to a control signal output by the control chip; the plurality of transformers arranged in series are used for converting input signals according to the driving of the driving unit and outputting a plurality of paths of constant current signals; the direct current blocking module carries out direct current blocking processing on the multi-path constant current signals; and the full-bridge module is connected with the blocking module, and is used for carrying out full-bridge processing on the multi-path constant-current signals processed by the blocking module and outputting multi-path constant-current output signals. On the premise that a plurality of power supplies do not need to be connected in parallel, by connecting a plurality of transformers in series, multi-path constant current output is achieved, the number of the power supplies is remarkably reduced, meanwhile, system efficiency can be improved, cost can be reduced, wiring errors can be avoided, and installation efficiency can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power supplies, and more specifically to a transformer-based multi-channel constant current output circuit and a driving power supply. Background Art

[0002] At present, for lamps with power above 100W on the market, when multiple constant current outputs are required or Class P certification is required, two or more power supplies need to be connected in parallel to meet the needs of the client. For example, when a customer needs a 400W lamp, four 100W power supplies need to be connected in parallel.

[0003] However, this implementation method will not only greatly increase the power supply cost, but also increase the manufacturing cost due to the large number of output wires. In addition, when this implementation method is installed at the client, since multiple power supplies are connected in parallel, repeated installation is required during wiring, which reduces the installation efficiency. When multiple power supplies are connected in parallel, the wiring is like a spider web, which is very complicated, further reducing the wiring efficiency and easily causing wiring errors. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a transformer-based multi-channel constant current output circuit and a driving power supply.

[0005] The technical solution adopted by the utility model to solve the technical problem is: constructing a transformer-based multi-channel constant current output circuit, including: a half-bridge module, a DC isolation module and a full-bridge module;

[0006] The half-bridge module comprises: a driving unit and a resonance unit connected to the driving unit; the resonance unit comprises: a plurality of transformers arranged in series;

[0007] The driving unit is connected to the control chip and is used to drive the resonance unit according to the control signal output by the control chip;

[0008] The plurality of transformers arranged in series convert input signals according to the driving of the driving unit and output multiple constant current signals;

[0009] The DC isolation module is connected to the secondary winding of each transformer respectively, and is used for performing DC isolation processing on the multiple constant current signals;

[0010] The full-bridge module is connected to the DC isolation module and is used to perform full-bridge processing on the multiple constant current signals processed by the DC isolation module and output multiple constant current output signals.

[0011] In the transformer-based multi-channel constant current output circuit of the utility model, the driving unit includes: a first switch tube and a second switch tube;

[0012] The first end of the first switch tube is connected to the upper tube driving end of the control chip, the second end of the first switch tube is connected to the input signal, and the third end of the first switch tube is connected to the resonance unit;

[0013] The first end of the second switch tube is connected to the lower tube driving end of the control chip, the second end of the second switch tube is connected to the third end of the first switch tube, and the third end of the second switch tube is grounded.

[0014] In the transformer-based multi-channel constant current output circuit described in the utility model, both the first switch tube and the second switch tube are MOS tubes.

[0015] In the transformer-based multi-channel constant current output circuit described in the utility model, the plurality of transformers arranged in series include: a first transformer and an Nth transformer, N being an integer greater than or equal to 1; the resonance unit also includes: a resonant inductor and a resonant capacitor;

[0016] The first transformer and the Nth transformer are connected in series through the primary winding, and the input end of the primary winding of the first transformer is connected to the third end of the first switching tube through the resonant inductor, and the output end of the primary winding of the Nth transformer is grounded through the resonant capacitor; the secondary winding of the first transformer and the secondary winding of the Nth transformer are arranged in parallel or independently output.

[0017] In the transformer-based multi-channel constant current output circuit described in the utility model, the DC isolation module includes: one or more DC isolation units; and when there are multiple DC isolation units, the multiple DC isolation units are arranged corresponding to the number of the multiple transformers arranged in series.

[0018] In the transformer-based multi-channel constant current output circuit described in the utility model, the DC isolation unit includes: a DC isolation capacitor;

[0019] The input end of the DC blocking capacitor is connected to the secondary winding of the transformer, and the output end of the DC blocking capacitor is connected to the full-bridge module.

[0020] In the transformer-based multi-channel constant current output circuit described in the utility model, the full-bridge module includes: one or more full-bridge units; and when there are multiple full-bridge units, the multiple full-bridge units are arranged corresponding to the number of the multiple transformers arranged in series.

[0021] In the transformer-based multi-channel constant current output circuit described in the utility model, each full-bridge unit outputs two channels of constant current output signals, and the input end of each full-bridge unit is connected to the DC isolation module.

[0022] In the transformer-based multi-channel constant current output circuit described in the utility model, each full-bridge unit includes: a first diode, a second diode, a third diode and a fourth diode;

[0023] The anode of the first diode and the cathode of the third diode are connected to the output end of the DC isolation module, the cathode of the first diode is connected to the first positive output end, the anode of the second diode and the cathode of the fourth diode are connected and connected to the resonance unit, the cathode of the second diode is connected to the second positive output end, and the cathode of the fourth diode and the anode of the third diode are connected to the negative output end.

[0024] The utility model also provides a driving power supply, comprising: the above-mentioned transformer-based multi-channel constant current output circuit.

[0025] The transformer-based multi-channel constant current output circuit of the utility model has the following beneficial effects: including: a half-bridge module, a direct current isolation module and a full-bridge module; the half-bridge module includes: a driving unit and a resonance unit connected to the driving unit; the resonance unit includes: a plurality of transformers arranged in series; the driving unit drives the resonance unit according to the control signal output by the control chip; the plurality of transformers arranged in series convert the input signal according to the drive of the driving unit, and output a plurality of constant current signals; the direct current isolation module performs direct current isolation processing on the multi-channel constant current signals; the full-bridge module is connected to the direct current isolation module, and is used to perform full-bridge processing on the multi-channel constant current signals processed by the direct current isolation module, and output a plurality of constant current output signals. The utility model realizes multi-channel constant current output by connecting a plurality of transformers in series without the need to connect a plurality of power supplies in parallel, significantly reduces the number of power supplies, and can also improve system efficiency, reduce costs, avoid wiring errors, and improve installation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0027] Figure 1 This is a principle block diagram of a transformer-based multi-channel constant current output circuit provided by the utility model;

[0028] Figure 2 This is a circuit diagram of Embodiment 1 of a transformer-based multi-channel constant current output circuit provided by the utility model;

[0029] Figure 3 This is a circuit diagram of Embodiment 2 of a transformer-based multi-channel constant current output circuit provided by the utility model;

[0030] Figure 4 This is a circuit diagram of Embodiment 3 of a transformer-based multi-channel constant current output circuit provided by the utility model;

[0031] Figure 5 This is a circuit diagram of Embodiment 4 of a transformer-based multi-channel constant current output circuit provided by the utility model. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0033] Figure 1 The schematic diagram of a preferred embodiment of a transformer-based multi-channel constant current output circuit provided by the utility model is shown.

[0034] This transformer-based multi-channel constant current output circuit can meet the client's high-power needs without the need to connect multiple power supplies in parallel, which can greatly reduce costs, simplify production complexity, reduce manufacturing costs, and improve efficiency, reduce wiring error rates, and improve installation reliability.

[0035] Specifically, Figure 1 As shown, the transformer-based multi-channel constant current output circuit includes: a half-bridge module, a DC isolation module and a full-bridge module. Among them, the half-bridge module includes: a driving unit and a resonant unit connected to the driving unit; the resonant unit includes: a plurality of transformers arranged in series.

[0036] In this embodiment, the driving unit is connected to the control chip, and is used to drive the resonance unit according to the control signal output by the control chip; multiple transformers arranged in series convert the input signal according to the drive of the driving unit, and output multiple constant current signals; the DC isolation module is respectively connected to the secondary winding of each transformer, and is used to isolate the multiple constant current signals; the full-bridge module is connected to the DC isolation module, and is used to perform full-bridge processing on the multiple constant current signals processed by the DC isolation module, and output multiple constant current output signals. Among them, the control chip is a main control chip commonly used in the primary side of the driving power supply, and the utility model does not make specific restrictions.

[0037] In this embodiment, multiple transformers are connected in series to achieve multi-channel constant current output, thereby reducing the number of power supplies, that is, the utility model only needs to use one power supply to achieve multi-channel constant current output, which can meet the client's needs for high power and multi-channel output without increasing costs. Optionally, in the embodiment of the utility model, the multiple transformers used are multiple identical LLC transformers. Among them, since the multiple transformers used are the same, the output current of the secondary winding of each transformer is the same, thereby achieving multi-channel constant current output.

[0038] Furthermore, in this embodiment, by providing a DC isolation module at the output end of the half-bridge module, the current and voltage of the multiple constant current outputs can be kept consistent, thereby ensuring the balance and consistency of the multiple constant current outputs.

[0039] In addition, the transformer-based multi-channel constant current output circuit of the utility model realizes multi-channel constant current output by adopting multiple transformers in series, and does not need to connect multiple power supplies in parallel, which significantly improves the installation efficiency and installation reliability of the client. For example, if four parallel power supplies are used, the original installation method is 4 inputs and 4 outputs. In the installation, the worker needs to repeat the installation 4 times to complete the wiring of the input end. After adopting the utility model, only one wiring is needed to complete the wiring of the input end. Obviously, this will greatly improve the installation efficiency of the client. For example, a client adopts the method of three power supplies in parallel, and its power supply efficiency can only reach 87%. After adopting the scheme of the utility model, the efficiency can reach 90%~91%, or even higher. This can reduce the number of lamp beads for the client and significantly reduce the cost of lamp beads. In addition, workers can also save labor costs when assembling the whole lamp. For example, the original method (taking the method of four power supplies in parallel as an example) needs to be repeated 4 times when wiring and installing, while the method of the utility model only needs to be installed once, so it can significantly save labor costs. Moreover, the original method of connecting multiple power supplies in parallel has connection lines that are like a spider web and are very complicated. Therefore, the wiring efficiency is very low and wiring errors are very likely to occur. The method of the utility model can greatly reduce the use of connecting lines. Therefore, the wiring efficiency is higher, wiring errors are less likely to occur, and the installation reliability is higher.

[0040] In some embodiments, the driving unit includes: a first switch tube and a second switch tube. The first end of the first switch tube is connected to the upper tube driving end of the control chip, the second end of the first switch tube is connected to the input signal, and the third end of the first switch tube is connected to the resonance unit; the first end of the second switch tube is connected to the lower tube driving end of the control chip, the second end of the second switch tube is connected to the third end of the first switch tube, and the third end of the second switch tube is grounded.

[0041] Optionally, in this embodiment, the first switch tube and the second switch tube are both MOS tubes.

[0042] In some embodiments, the plurality of transformers connected in series include: a first transformer and an Nth transformer, where N is an integer greater than or equal to 1; and the resonance unit further includes: a resonant inductor and a resonant capacitor.

[0043] The first transformer and the Nth transformer are connected in series through the primary winding, and the input end of the primary winding of the first transformer is connected to the third end of the first switch tube through a resonant inductor, and the output end of the primary winding of the Nth transformer is grounded through a resonant capacitor; the secondary winding of the first transformer and the secondary winding of the Nth transformer are arranged in parallel or independently output.

[0044] In some embodiments, the DC isolation module includes: one or more DC isolation units; and when there are multiple DC isolation units, the multiple DC isolation units are arranged corresponding to the number of the multiple transformers arranged in series.

[0045] The DC isolation unit comprises: a DC isolation capacitor; the input end of the DC isolation capacitor is connected to the secondary winding of the transformer, and the output end of the DC isolation capacitor is connected to the full-bridge module.

[0046] In some embodiments, the full-bridge module includes: one or more full-bridge units; and when there are multiple full-bridge units, the multiple full-bridge units are arranged corresponding to the number of multiple transformers arranged in series. Each full-bridge unit outputs two constant current output signals, and the input end of each full-bridge unit is connected to the DC isolation module.

[0047] In some embodiments, each full-bridge unit includes: a first diode, a second diode, a third diode and a fourth diode; the anode of the first diode and the cathode of the third diode are connected to the output end of the DC isolation module, the cathode of the first diode is connected to the first positive output end, the anode of the second diode and the cathode of the fourth diode are connected and connected to the resonant unit, the cathode of the second diode is connected to the second positive output end, and the cathode of the fourth diode and the anode of the third diode are connected to the negative output end.

[0048] The principle of the present utility model is described below with reference to specific embodiments.

[0049] refer to Figure 2 , Figure 2 This is a circuit diagram of Embodiment 1 of a transformer-based multi-channel constant current output circuit provided by the utility model.

[0050] Specifically, Figure 2 As shown, in this embodiment, the resonance unit includes: two transformers, transformer T1 and transformer T2, wherein the transformer T1 and transformer T2 are arranged in series by connecting the primary windings in series, and the secondary windings of the transformer T1 and transformer T2 are arranged in parallel.

[0051] like Figure 2 As shown, the driving unit includes: MOS transistor Q3 and MOS transistor Q4. In this embodiment, the resonance unit also includes: resonance inductor L1 and resonance capacitor L1.

[0052] like Figure 2As shown, the DC isolation module includes: a DC isolation unit, and the DC isolation unit includes: a DC isolation capacitor C2.

[0053] like Figure 2 As shown, in this embodiment, the full-bridge module includes: a full-bridge unit. The full-bridge unit includes: a diode D1, a diode D2, a diode D3 and a diode D4.

[0054] Specifically, Figure 2 As shown, the gate of the MOS tube Q3 is connected to the upper tube driving end of the control chip (i.e., HSG in the figure), the drain of the MOS tube Q3 is connected to the positive end of the PFC electrolytic capacitor to access VBUS, the source of the MOS tube Q3 is connected to the drain of the MOS tube Q5 and the first end of the resonant inductor L1, the gate of the MOS tube Q5 is connected to the lower tube driving end of the control chip (i.e., LSG in the figure), the source of the MOS tube Q5 is grounded and the first end of the resonant capacitor C1, the second end of the resonant inductor L1 is connected to the first end of the transformer T1, the third end of the transformer T1 is connected to the first end of the transformer T2, the third end of the transformer T2 is connected to the second end of the resonant capacitor C1, and the transformer The seventh end of T1 and the seventh end of transformer T2 are connected to the first end of DC blocking capacitor C2, the sixth end of transformer T1 and the sixth end of transformer T2 are connected to the cathode of diode D4 and the anode of diode D2, the second end of DC blocking capacitor C2 is connected to the anode of diode D1 and the cathode of diode D3, the cathode of diode D1 is connected to the first positive output end (i.e. LED1+) and the first end of energy storage capacitor C3, the anode of diode D4 is connected to the second end of energy storage capacitor C3 and the negative output end (i.e. LED-), the anode of diode D3 is connected to the negative output end and the second end of energy storage capacitor C4, and the cathode of diode D2 is connected to the second positive output end (i.e. LED2+).

[0055] like Figure 2 As shown, by using transformer T1 and transformer T2 to divide VBUS in series, and because transformer T1 and transformer T2 are the same transformer, the outputs of the secondary windings of the two transformers are the same, that is, multi-channel constant current output is achieved.

[0056] refer to Figure 3 , Figure 3 This is a circuit diagram of Embodiment 2 of a transformer-based multi-channel constant current output circuit provided by the utility model.

[0057] Specifically, Figure 3 As shown, in this embodiment, the resonance unit includes: two transformers, transformer T3 and transformer T4, wherein the transformer T3 and transformer T4 are connected in series by connecting the primary windings in series, and the secondary windings of the transformer T3 and transformer T4 are independently output.

[0058] like Figure 3As shown, the driving unit includes: MOS transistor Q1 and MOS transistor Q2. In this embodiment, the resonance unit also includes: resonance inductor L2 and resonance capacitor C5.

[0059] like Figure 3 As shown, the DC isolation module includes: two DC isolation units, wherein the first DC isolation unit includes: a DC isolation capacitor C6, and the second DC isolation unit includes: a DC isolation capacitor C9.

[0060] like Figure 3 As shown, in this embodiment, the full-bridge module includes: two full-bridge units. The first full-bridge unit includes: diode D5, diode D6, diode D7 and diode D8. The second full-bridge unit includes: diode D9, diode D10, diode D11 and diode D12.

[0061] Specifically, Figure 3 As shown, the gate of the MOS tube Q1 is connected to the upper tube driving end of the control chip (i.e., HSG in the figure), the drain of the MOS tube Q1 is connected to the positive end of the PFC electrolytic capacitor to access VBUS, the source of the MOS tube Q1 is connected to the drain of the MOS tube Q2 and the first end of the resonant inductor L2, the gate of the MOS tube Q2 is connected to the lower tube driving end of the control chip (i.e., LSG in the figure), the source of the MOS tube Q2 is grounded and the first end of the resonant capacitor C5, the second end of the resonant inductor L2 is connected to the first end of the transformer T3, the third end of the transformer T3 is connected to the first end of the transformer T4, and the third end of the transformer T4 is connected to the resonant capacitor The second end of C5 and the seventh end of the transformer T3 are connected to the first end of the DC blocking capacitor C6, the sixth end of the transformer T3 is connected to the cathode of the diode D8 and the anode of the diode D6, the second end of the DC blocking capacitor C6 is connected to the anode of the diode D5 and the cathode of the diode D7, the cathode of the diode D5 is connected to the first positive output terminal (i.e., LED1+) and the first end of the energy storage capacitor C7, the anode of the diode D8 is connected to the second end of the energy storage capacitor C7 and the negative output terminal (i.e., LED-), the anode of the diode D7 is connected to the negative output terminal and the second end of the energy storage capacitor C8, and the cathode of the diode D6 is connected to the second positive output terminal (i.e., LED2+).

[0062] The seventh end of the transformer T4 is connected to the first end of the DC blocking capacitor C9, the sixth end of the transformer T4 is connected to the anode of the diode D12 and the anode of the diode D10, the second end of the DC blocking capacitor C9 is connected to the anode of the diode D9 and the cathode of the diode D11, the cathode of the diode D9 is connected to the third positive output terminal (i.e., LED3+) and the first end of the energy storage capacitor C10, the anode of the diode D12 is connected to the second end of the energy storage capacitor C10 and the negative output terminal (i.e., LED-), the anode of the diode D11 is connected to the negative output terminal and the second end of the energy storage capacitor C11, and the cathode of the diode D10 is connected to the fourth positive output terminal (i.e., LED4+).

[0063] like Figure 3 As shown, by using transformer T3 and transformer T4 to divide VBUS in series, and because transformer T3 and transformer T4 are the same transformer, the outputs of the secondary windings of the two transformers are the same, that is, multi-channel constant current output is achieved.

[0064] refer to Figure 4 , Figure 4 This is a circuit diagram of Embodiment 3 of a transformer-based multi-channel constant current output circuit provided by the utility model.

[0065] Specifically, Figure 4 As shown, in this embodiment, the resonant unit includes: three transformers, namely transformer T5, transformer T6 and transformer T7. Transformers T5, transformer T6 and transformer T7 are connected in series by connecting their primary windings in series, and the secondary windings of transformers T5, transformer T6 and transformer T7 are connected in parallel.

[0066] like Figure 4 As shown, the driving unit includes: MOS transistor Q4 and MOS transistor Q6. In this embodiment, the resonance unit also includes: resonance inductor L3 and resonance capacitor C12.

[0067] like Figure 4 As shown, the DC isolation module includes: a DC isolation unit. The DC isolation unit includes: a DC isolation capacitor C13.

[0068] like Figure 4 As shown, in this embodiment, the full-bridge module includes: a full-bridge unit. The full-bridge unit includes: a diode D13, a diode D14, a diode D15 and a diode D16.

[0069] Specifically, Figure 4As shown, the gate of the MOS tube Q4 is connected to the upper tube driving end of the control chip (i.e., HSG in the figure), the drain of the MOS tube Q4 is connected to the positive end of the PFC electrolytic capacitor to access VBUS, the source of the MOS tube Q4 is connected to the drain of the MOS tube Q6 and the first end of the resonant inductor L3, the gate of the MOS tube Q6 is connected to the lower tube driving end of the control chip (i.e., LSG in the figure), the source of the MOS tube Q6 is grounded and the first end of the resonant capacitor C12, the second end of the resonant inductor L3 is connected to the first end of the transformer T5, the third end of the transformer T5 is connected to the first end of the transformer T6, the third end of the transformer T6 is connected to the first end of the transformer T7, the third end of the transformer T7 is connected to the second end of the resonant capacitor C12, and the seventh end of the transformer T5 is connected to the first end of the transformer T6. The first end of the transformer T5, the seventh end of the transformer T6 and the seventh end of the transformer T7 are all connected to the first end of the DC blocking capacitor C13, the sixth end of the transformer T5, the sixth end of the transformer T6 and the sixth end of the transformer T7 are all connected to the cathode of the diode D16 and the anode of the diode D14, the second end of the DC blocking capacitor C13 is connected to the anode of the diode D13 and the cathode of the diode D15, the cathode of the diode D13 is connected to the first positive output end (i.e., LED1+) and the first end of the energy storage capacitor C7, the anode of the diode D16 is connected to the second end of the energy storage capacitor C14 and the negative output end (i.e., LED-), the anode of the diode D15 is connected to the negative output end and the second end of the energy storage capacitor C15, and the cathode of the diode D14 is connected to the second positive output end (i.e., LED2+).

[0070] like Figure 4 As shown, by using transformer T5, transformer T6 and transformer T7 to divide VBUS in series, and because transformer T5, transformer T6 and transformer T7 are the same transformer, the outputs of the secondary windings of the three transformers are the same, that is, multi-channel constant current output is achieved.

[0071] refer to Figure 5 , Figure 5 This is a circuit diagram of Embodiment 3 of a transformer-based multi-channel constant current output circuit provided by the utility model.

[0072] Specifically, Figure 5 As shown, in this embodiment, the resonant unit includes: three transformers, namely transformer T8, transformer T9 and transformer T10. Transformers T8, transformer T9 and transformer T10 are connected in series by connecting their primary windings in series, and the secondary windings of transformers T8, transformer T9 and transformer T10 are independently output.

[0073] like Figure 5 As shown, the driving unit includes: MOS transistor Q7 and MOS transistor Q8. In this embodiment, the resonance unit also includes: resonance inductor L4 and resonance capacitor C16.

[0074] like Figure 5As shown, the DC isolation module includes: three DC isolation units. The first DC isolation unit includes: a DC isolation capacitor C17, the second DC isolation unit includes: a DC isolation capacitor C20, and the third DC isolation unit includes: a DC isolation capacitor C23.

[0075] like Figure 5 As shown, in this embodiment, the full-bridge module includes: three full-bridge units. The first full-bridge unit includes: a diode D17, a diode D18, a diode D19 and a diode D20.

[0076] Specifically, Figure 5 As shown, the gate of the MOS tube Q7 is connected to the upper tube driving end of the control chip (i.e., HSG in the figure), the drain of the MOS tube Q7 is connected to the positive end of the PFC electrolytic capacitor to access VBUS, the source of the MOS tube Q7 is connected to the drain of the MOS tube Q8 and the first end of the resonant inductor L4, the gate of the MOS tube Q8 is connected to the lower tube driving end of the control chip (i.e., LSG in the figure), the source of the MOS tube Q8 is grounded and the first end of the resonant capacitor C12, the second end of the resonant inductor L4 is connected to the first end of the transformer T8, the third end of the transformer T8 is connected to the first end of the transformer T9, and the third end of the transformer T9 is connected to the transformer T10 The first end of the transformer T10 is connected to the second end of the resonant capacitor C16, the seventh end of the transformer T8 is connected to the first end of the DC blocking capacitor C17, the second end of the DC blocking capacitor C17 is connected to the anode of the diode D17 and the cathode of the diode D19, the cathode of the diode D17 is connected to the first positive output terminal (i.e., LED1+) and the first end of the energy storage capacitor C18, the anode of the diode D20 is connected to the second end of the energy storage capacitor C18 and the negative output terminal (i.e., LED-), the anode of the diode D19 is connected to the negative output terminal and the second end of the energy storage capacitor C19, and the cathode of the diode D18 is connected to the second positive output terminal (i.e., LED2+).

[0077] The seventh end of the transformer T9 is connected to the first end of the DC blocking capacitor C20, the second end of the DC blocking capacitor C20 is connected to the anode of the diode D21 and the cathode of the diode D23, the cathode of the diode D21 is connected to the third positive output terminal (i.e., LED3+) and the first end of the energy storage capacitor C21, the anode of the diode D24 is connected to the second end of the energy storage capacitor C21 and the negative output terminal (i.e., LED-), the anode of the diode D23 is connected to the negative output terminal and the second end of the energy storage capacitor C22, and the cathode of the diode D22 is connected to the fourth positive output terminal (i.e., LED4+).

[0078] The seventh end of the transformer T10 is connected to the first end of the DC blocking capacitor C23, the second end of the DC blocking capacitor C23 is connected to the anode of the diode D25 and the cathode of the diode D27, the cathode of the diode D25 is connected to the fifth positive output terminal (i.e., LED5+) and the first end of the energy storage capacitor C24, the anode of the diode D28 is connected to the second end of the energy storage capacitor C24 and the negative output terminal (i.e., LED-), the anode of the diode D27 is connected to the negative output terminal and the second end of the energy storage capacitor C25, and the cathode of the diode D26 is connected to the sixth positive output terminal (i.e., LED6+).

[0079] like Figure 5 As shown, by using transformer T8, transformer T9 and transformer T10 to divide VBUS in series, and because transformer T8, transformer T9 and transformer T10 are the same transformer, the outputs of the secondary windings of the three transformers are the same, that is, multi-channel constant current output is achieved.

[0080] in, Figures 2 to 5 11 in the figure only shows the upper tube driving end and the lower tube driving end of the control chip.

[0081] The utility model also provides a driving power supply, comprising: the above transformer-based multi-channel constant current output circuit. Optionally, the driving power supply can be an LED driving power supply.

[0082] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot limit the protection scope of the utility model. All equivalent changes and modifications made to the scope of the claims of the utility model should fall within the scope of the claims of the utility model.

Claims

1. A transformer-based multi-channel constant current output circuit, characterized in that: include: Half-bridge modules, DC isolation modules and full-bridge modules; The half-bridge module comprises: a driving unit and a resonance unit connected to the driving unit; the resonance unit comprises: a plurality of transformers arranged in series; The driving unit is connected to the control chip and is used to drive the resonance unit according to the control signal output by the control chip; The plurality of transformers arranged in series convert input signals according to the driving of the driving unit and output multiple constant current signals; The DC isolation module is connected to the secondary winding of each transformer respectively, and is used for performing DC isolation processing on the multiple constant current signals; The full-bridge module is connected to the DC isolation module and is used to perform full-bridge processing on the multiple constant current signals processed by the DC isolation module and output multiple constant current output signals.

2. The transformer-based multi-channel constant current output circuit according to claim 1, characterized in that: The driving unit includes: a first switch tube and a second switch tube; The first end of the first switch tube is connected to the upper tube driving end of the control chip, the second end of the first switch tube is connected to the input signal, and the third end of the first switch tube is connected to the resonance unit; The first end of the second switch tube is connected to the lower tube driving end of the control chip, the second end of the second switch tube is connected to the third end of the first switch tube, and the third end of the second switch tube is grounded.

3. The transformer-based multi-channel constant current output circuit according to claim 2, characterized in that: The first switch tube and the second switch tube are both MOS tubes.

4. The transformer-based multi-channel constant current output circuit according to claim 2, characterized in that: The plurality of transformers connected in series include: a first transformer and an Nth transformer, where N is an integer greater than or equal to 1; the resonance unit further includes: a resonance inductor and a resonance capacitor; The first transformer and the Nth transformer are connected in series through the primary winding, and the input end of the primary winding of the first transformer is connected to the third end of the first switching tube through the resonant inductor, and the output end of the primary winding of the Nth transformer is grounded through the resonant capacitor; the secondary winding of the first transformer and the secondary winding of the Nth transformer are arranged in parallel or independently output.

5. The transformer-based multi-channel constant current output circuit according to claim 1, characterized in that: The DC isolation module includes: one or more DC isolation units; and when there are multiple DC isolation units, the multiple DC isolation units are arranged corresponding to the number of the multiple transformers arranged in series.

6. The transformer-based multi-channel constant current output circuit according to claim 5, characterized in that: The DC isolation unit comprises: a DC isolation capacitor; The input end of the DC blocking capacitor is connected to the secondary winding of the transformer, and the output end of the DC blocking capacitor is connected to the full-bridge module.

7. The transformer-based multi-channel constant current output circuit according to claim 1, characterized in that: The full-bridge module includes: one or more full-bridge units; and when there are multiple full-bridge units, the multiple full-bridge units are arranged corresponding to the number of the multiple transformers arranged in series.

8. The transformer-based multi-channel constant current output circuit according to claim 7, characterized in that: Each full-bridge unit outputs two constant current output signals, and the input end of each full-bridge unit is connected to the DC isolation module.

9. The transformer-based multi-channel constant current output circuit according to claim 8, characterized in that: Each full-bridge unit includes: a first diode, a second diode, a third diode and a fourth diode; The anode of the first diode and the cathode of the third diode are connected to the output end of the DC isolation module, the cathode of the first diode is connected to the first positive output end, the anode of the second diode and the cathode of the fourth diode are connected and connected to the resonance unit, the cathode of the second diode is connected to the second positive output end, and the cathode of the fourth diode and the anode of the third diode are connected to the negative output end.

10. A driving power supply, characterized in that: include: A transformer-based multi-channel constant current output circuit as described in any one of claims 1 to 9.

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