AHB multi-port charger and method for reducing negative resonance current
By setting a voltage regulation module in the AHB multi-port charger and controlling the disconnection of the voltage regulation unit with the main control chip, the voltage matching is dynamically adjusted, which solves the negative resonant current problem of the AHB topology circuit during hot plugging or rapid output changes, and achieves low power consumption and high-efficiency voltage regulation.
Patent Information
- Application Number
- CN202510902655.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-30
- Publication Date
- 2025-09-12
AI Technical Summary
Existing AHB topology circuits are prone to generating large negative resonant currents during hot plugging or rapid output voltage changes, damaging devices and increasing power consumption. Existing solutions also have the problems of high power consumption or unsatisfactory suppression effects.
An AHB multi-port charger is designed. A voltage regulator module is set between the output module and the feedback module. The main control chip is used to control the voltage regulator unit to gradually disconnect and dynamically adjust the reference voltage of the reference voltage source to match the input and output voltage difference, reduce power device loss and suppress negative resonant current.
In a wide voltage output environment, it effectively reduces the conduction loss and switching loss of power devices, improves product efficiency, and suppresses reverse resonant current by gradually reducing the input voltage when the output voltage changes rapidly, avoiding voltage difference loss.
Smart Images
Figure CN120638570A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of power supplies, and in particular to an AHB multi-port charger and a method for reducing negative resonant current. Background Art
[0002] In circuits designed to reduce negative resonant current, such as those in the 100-300W range, the LLC topology, which can only operate within a narrow output range, has been gradually replaced by the AHB topology, which can operate within a wide output range. However, during hot-swap or when the output voltage rapidly changes from high to low, the AHB topology can generate large negative resonant currents in the primary circuit, damaging components such as the switch. To address this problem, a resistor is typically connected in parallel with the resonant capacitor to reduce the negative resonant current. This approach has several drawbacks. First, the resistor connected in parallel with the resonant capacitor continuously consumes power. Using a small-value discharge resistor increases power consumption, affecting product efficiency. Using a large-value discharge resistor results in suboptimal negative resonant current suppression. Second, when the output voltage changes rapidly and significantly, a larger-specification device is required, significantly impacting product reliability and production costs.
[0003] Therefore, it is crucial for those skilled in the art to design an AHB multi-port charger with low power consumption and good negative resonant current suppression effect, as well as a method for reducing negative resonant current. Summary of the Invention
[0004] The embodiments of the present invention provide an AHB multi-port charger with low power consumption and good negative resonant current suppression effect, and a method for reducing negative resonant current, so as to solve the problems of unsatisfactory suppression effect and high power consumption in the prior art.
[0005] The present invention provides an AHB multi-port charger, which includes: a power supply module, a main control chip, a reference voltage source, a feedback module, a voltage regulation module and an output module, wherein the voltage input end of the power supply module is used to connect to an external mains power supply, the voltage output end of the power supply module is connected to the voltage input end of the output module, and the voltage output end of the output module is used to connect to an external device. The voltage regulation module includes multiple parallel voltage regulation units, one end of each of the multiple voltage regulation units is connected to the output module, and the other end of each of the multiple voltage regulation units is connected to the reference end of the reference voltage source, the anode of the reference voltage source is grounded, the cathode of the reference voltage source is connected to the input end of the feedback module, the output end of the feedback module is connected to the feedback pin of the main control chip, and the control pin of the main control chip is connected to the power supply module.
[0006] Optionally, the voltage regulating module includes a first voltage regulating unit, a second voltage regulating unit and a third voltage regulating unit, one end of the first voltage regulating unit, the second voltage regulating unit and the third voltage regulating unit are all connected to the reference end of the reference voltage source, and the other end of the first voltage regulating unit, the second voltage regulating unit and the third voltage regulating unit are all connected to the output module.
[0007] Optionally, the first voltage regulating unit is a first resistor, the second voltage regulating unit is a second resistor, and the third voltage regulating unit is a third resistor.
[0008] Optionally, the first voltage regulating unit includes a first switching tube and a fourth resistor, the second voltage regulating unit includes a second switching tube and a fifth resistor, and the third voltage regulating unit includes a third switching tube and a sixth resistor. One end of the fourth resistor, the fifth resistor, and the sixth resistor are all connected to the reference end of the reference voltage source, the other end of the fourth resistor is connected to the drain of the first switching tube, the other end of the fifth resistor is connected to the drain of the second switching tube, and the other end of the sixth resistor is connected to the drain of the third switching tube. The sources of the first switching tube, the second switching tube, and the third switching tube are all grounded, and the gates of the first switching tube, the second switching tube, and the third switching tube are all connected to the output module.
[0009] Optionally, the voltage regulation module further includes a seventh resistor and an eighth resistor, one end of each of the seventh resistor and the eighth resistor is connected to the reference end of the reference voltage source, and the other end of each of the seventh resistor and the eighth resistor is grounded.
[0010] Optionally, the feedback module is a photoelectric coupler, the input end of the feedback module is a light emitting diode of the photoelectric coupler, and the output end of the feedback module is a phototransistor of the photoelectric coupler.
[0011] Optionally, the output module includes multiple output units, the voltage input ends of the multiple output units are connected to the voltage output end of the power supply module, and the signal output end of one output unit is connected to the voltage regulation module.
[0012] Optionally, the output module includes a first output unit, a second output unit and a third output unit, the voltage input ends of the first output unit, the second output unit and the third output unit are all connected to the voltage output end of the power supply module, the control end of the first output unit is connected to the voltage regulating module, and the voltage output ends of the first output unit, the second output unit and the third output unit are all used to connect to external devices.
[0013] Optionally, the first output unit includes a first protocol chip, the second output unit includes a second protocol chip, and the third output unit includes a third protocol chip. The control end of the first protocol chip is connected to the voltage regulation module, and the second protocol chip and the third protocol chip are both connected to the first protocol chip via an I2C bus.
[0014] To solve the problems existing in the prior art, the present invention further provides a method for reducing negative resonant current, which is implemented by any of the above-mentioned AHB multi-port chargers, including the following steps: When the output terminal voltage of the output module changes from high to low, the output module controls the multiple voltage regulating units in the voltage regulating module to be gradually disconnected at preset time intervals, so as to gradually adjust the reference voltage of the reference voltage source; Feedback the reference voltage to the main control chip through the feedback module; The main control chip controls the power supply module according to the feedback voltage to gradually reduce the output voltage of the power supply module.
[0015] The beneficial effects of the AHB multi-port charger provided by the embodiment of the present invention are: by designing an AHB multi-port charger, a voltage regulating module is provided between the output module and the feedback module. The output module can control the multiple voltage regulating units in the voltage regulating module to be disconnected in sequence according to its output voltage change to adjust the feedback voltage. The main control chip can control the power supply module to adjust its output voltage according to the adjusted feedback voltage. This scheme can dynamically adjust its input voltage according to the output voltage of the output module, thereby realizing dynamic matching of the input and output voltage difference. In a wide voltage output environment, it can not only effectively reduce the conduction loss and switching loss of the power device, but also can synchronously reduce its input voltage when the output voltage demand of the output module is reduced, effectively avoiding voltage difference loss and improving product efficiency. Moreover, when the output voltage of the output module changes too rapidly, the output voltage change difference can be reduced by gradually reducing the input voltage of the output module, thereby effectively suppressing the reverse resonant current. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, in which: Figure 1 This is a schematic diagram of an AHB multi-port charger in an embodiment of the present invention. Figure 1 ; Figure 2 is a circuit diagram of a power supply module in an embodiment of the present invention; Figure 3 The circuit of the voltage regulating module in the embodiment of the present invention is Figure 1 ; Figure 4 The circuit of the voltage regulating module in the embodiment of the present invention is Figure 2 ; Figure 5 This is a schematic diagram of an AHB multi-port charger in an embodiment of the present invention. Figure 2 ; Figure 6 is a circuit diagram of a first output unit in an embodiment of the present invention; Figure 7 is a circuit diagram of a second output unit in an embodiment of the present invention; Figure 8 is a circuit diagram of a third output unit in an embodiment of the present invention; Figure 9 4 is a flow chart of a method for reducing negative resonant current in an embodiment of the present invention.
[0017] The reference numerals in the figures are: 100, power supply module; 200, main control chip; 300, reference voltage source; 400, feedback module; 500, voltage regulation module; 600, output module; 110, mains input circuit; 120, rectifier and filter circuit; 130, PFC circuit; 150, secondary rectifier circuit; 510, first voltage regulation unit; 520, second voltage regulation unit; 530, third voltage regulation unit; M2, high-voltage MOS transistor; M3, low-voltage MOS transistor; T1A, transformer; R48, seventh resistor; R49, eighth resistor; R51, first resistor; R54, second resistor; R52, third resistor; R93, fourth resistor; R95, fourth resistor; R97, fourth resistor. DETAILED DESCRIPTION
[0018] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. Now, in conjunction with the accompanying drawings, the preferred embodiments of the present invention will be described in detail.
[0019] like Figure 1 like Figure 8 As shown, the present invention discloses a specific embodiment of an AHB multi-port charger.
[0020] An AHB multi-port charger, reference Figure 1 The AHB multi-port charger includes a power supply module 100, a main control chip 200, a reference voltage source 300, a feedback module 400, a voltage regulation module 500 and an output module 600. The voltage input end of the power supply module 100 is used to connect to the external AC power to obtain external AC power. The voltage output end of the power supply module 100 is connected to the voltage input end of the output module 600. The power supply module 100 is used to convert the external AC power into DC power and output the required voltage to the output module 600. The voltage output end of the output module 600 is used to connect to an external device to charge the external device.
[0021] The voltage regulating module 500 includes multiple parallel voltage regulating units, one end of each of the multiple voltage regulating units is connected to the output module 600, and the other end of each of the multiple voltage regulating units is connected to the reference end of the reference voltage source 300, the anode of the reference voltage source 300 is grounded, the cathode of the reference voltage source 300 is connected to the input end of the feedback module 400, the output end of the feedback module 400 is connected to the feedback pin of the main control chip 200, and the control pin of the main control chip 200 is connected to the power supply module 100.
[0022] Specifically, refer to Figure 1 and Figure 2 The power supply module 100 includes a mains input circuit 110, a rectifier and filter circuit 120, a PFC circuit 130, an AHB circuit, and a secondary rectifier circuit 150. The mains input circuit 110 is connected to an external mains to obtain 100-240V AC power. The voltage input end of the rectifier and filter circuit 120 is connected to the voltage output end of the mains input circuit 110. The rectifier and filter circuit 120 includes a full-bridge rectifier bridge and an energy storage capacitor. The full-bridge rectifier bridge rectifies the 100-240V AC power into DC power to obtain 200 to 400V high-voltage DC power.
[0023] refer to Figure 1 and Figure 2 The voltage output end of the rectifier and filter circuit 120 is connected to the voltage input end of the AHB circuit. The AHB circuit includes a high-voltage MOS transistor M2, a low-voltage MOS transistor M3, a resonant inductor, and a transformer T1A. The gate G of the high-voltage MOS transistor M2 and the gate G of the low-voltage MOS transistor M3 are respectively connected to the control pin HS-GD and the control pin LS-GD of the main control chip 200. The source S of the high-voltage MOS transistor M2 is connected to the drain D of the low-voltage MOS transistor M3. The source S of the low-voltage MOS transistor M3 is grounded. The drain D of the high-voltage MOS transistor M2 is connected to the voltage output end of the rectifier and filter circuit 120. The primary side of the transformer T1A is connected between the source S of the high-voltage MOS transistor M2 and the drain D of the low-voltage MOS transistor M3. The secondary side of the transformer T1A is connected to the output module 600. The main control chip 200 can adjust the voltage on the primary side of the transformer T1A by controlling the conduction time of the high-voltage MOS transistor M2 and the low-voltage MOS transistor M3, thereby adjusting the output voltage on the secondary side of the transformer T1A.
[0024] Further, refer to Figure 1The voltage regulating module 500 includes multiple voltage regulating units, which are connected in parallel and arranged between the reference end of the reference voltage source 300 and the output module 600. The anode of the reference voltage source 300 is grounded, the cathode of the reference voltage source 300 is connected to the input end of the feedback module 400, and the output end of the feedback module 400 is connected to the feedback pin of the main control chip 200. The output module 600 can control one or more of the multiple voltage regulating units to be disconnected according to the change of its output voltage, thereby adjusting the voltage of the reference end of the reference voltage source 300, that is, adjusting the reference voltage of the reference voltage source 300. When the reference voltage of the reference voltage source 300 changes, it will be fed back to the main control chip through the feedback module 400. The main control chip 200 controls the conduction time of the high-voltage MOS transistor M2 and the low-voltage MOS transistor M3 according to the feedback voltage received by the feedback pin to adjust the voltage on the primary side of the transformer T1A, thereby adjusting the output voltage on the secondary side of the transformer T1A, so as to reduce the voltage difference between the input and output ends of the output module 600, thereby improving the efficiency of the product; and when the output voltage of the output module 600 changes rapidly from high to low, the output module 600 can gradually control the disconnection of multiple voltage regulating units, so that the output voltage of the power supply module 100 slowly decreases, thereby reducing the output voltage change difference, thereby achieving the effect of reducing the negative resonant current.
[0025] In this embodiment, an AHB multi-port charger is designed, which sets a voltage regulating module 500 between the output module 600 and the feedback module 400, and controls the multiple voltage regulating units in the voltage regulating module 500 to be disconnected in sequence according to the output voltage change of the output module 600 to adjust the feedback voltage, and controls the power supply module 100 to adjust its output voltage according to the adjusted feedback voltage through the main control chip 200. This scheme can dynamically adjust its input voltage according to the output voltage of the output module 600, thereby realizing dynamic matching of the input and output voltage difference. In a wide voltage output environment, it can not only effectively reduce the conduction loss and switching loss of the power device, but also can synchronously reduce its input voltage when the output voltage demand of the output module 600 is reduced, effectively avoiding voltage difference loss and improving product efficiency. Moreover, when the output voltage of the output module 600 changes too rapidly, the output voltage change difference can be reduced by gradually reducing the input voltage of the output module 600, thereby effectively suppressing the reverse resonant current.
[0026] In one embodiment, reference Figure 1 and Figure 3The voltage regulating module 500 includes a seventh resistor R48, an eighth resistor R49, a first voltage regulating unit 510, a second voltage regulating unit 520, and a third voltage regulating unit 530. The seventh resistor R48 and the eighth resistor R49 are connected in parallel, and one end of the seventh resistor R48 and the eighth resistor R49 are both connected to the reference end of the reference voltage source 300, and the other ends of the seventh resistor R48 and the eighth resistor R49 are both grounded. One end of the first voltage regulating unit 510, the second voltage regulating unit 520, and the third voltage regulating unit 530 are all connected to the reference end of the reference voltage source 300, and the other ends of the first voltage regulating unit 510, the second voltage regulating unit 520, and the third voltage regulating unit 530 are all connected to the output module 600.
[0027] Option 1 refer to Figure 1 and Figure 3 The first voltage regulating unit 510 is a first resistor R51, the second voltage regulating unit 520 is a second resistor R54, and the third voltage regulating unit 530 is a third resistor R52. One end of the first resistor R51 is connected to the reference end of the reference voltage source 300, and the other end of the first resistor R51 is connected to the first control end ON / OFF2 of the output module 600. One end of the second resistor R54 is connected to the reference end of the reference voltage source 300, and the other end of the second resistor R54 is connected to the second control end ON / OFF1 of the output module 600. One end of the third resistor R52 is connected to the reference end of the reference voltage source 300, and the other end of the third resistor R52 is connected to the third control end ON / OFF3 of the output module 600.
[0028] When the output module 600 has no output voltage or the output voltage is at a low voltage (such as 0V-9V), the first control terminal ON / OFF2, the second control terminal ON / OFF1 and the third control terminal ON / OFF3 of the output module 600 are in a high-impedance state, and the corresponding first resistor R51, the second resistor R54 and the third resistor R52 have no effect on the reference voltage of the reference voltage source 300. The output voltage of the power supply module 100 is transmitted to the reference terminal of the reference voltage source 300 by the resistor R50, the seventh resistor R48 and the eighth resistor R49, and is fed back to the feedback pin of the main control chip 200 through the feedback module 400. The main control chip 200 controls the power supply module 100 to output a fixed voltage of 12-15V according to the feedback voltage received by the feedback pin. The specific voltage value can be selected according to specific needs.
[0029] When the output voltage of the output module 600 is at an intermediate voltage (such as 9-15V), the first control terminal ON / OFF2 of the output module 600 is in a low level state to pull down the first resistor R51, so that the first resistor R51 is connected in parallel with the seventh resistor R48 and the eighth resistor R49 to adjust the reference voltage of the reference voltage source 300 and feedback it to the feedback pin of the main control chip 200 through the feedback module 400. The main control chip 200 controls the power supply module 100 to increase the voltage to 17-20V according to the feedback voltage received by the feedback pin. The specific increased voltage value can be adjusted by adjusting the resistance value of the first resistor R51.
[0030] When the output voltage of the output module 600 is at a high voltage (such as 15-21V), the second control terminal ON / OFF1 of the output module 600 is in a low level state to pull down the second resistor R54, so that the second resistor R54 is connected in parallel with the seventh resistor R48 and the eighth resistor R49 to adjust the reference voltage of the reference voltage source 300 and feedback it to the feedback pin of the main control chip 200 through the feedback module 400. The main control chip 200 controls the power supply module 100 to increase the voltage to 20-22V according to the feedback voltage received by the feedback pin. The specific increased voltage value can be adjusted by adjusting the resistance value of the second resistor R54.
[0031] When the output voltage of the output module 600 is at a high voltage (such as 21-28V), the third control terminal ON / OFF3 of the output module 600 is in a low level state to pull down the third resistor R52, so that the third resistor R52 is connected in parallel with the seventh resistor R48 and the eighth resistor R49 to adjust the reference voltage of the reference voltage source 300 and feedback it to the feedback pin of the main control chip 200 through the feedback module 400. The main control chip 200 controls the power supply module 100 to increase the voltage to 28-30V according to the feedback voltage received by the feedback pin. The specific increased voltage value can be adjusted by adjusting the resistance value of the third resistor R52.
[0032] Through the above-mentioned control principle, the output module 600 can control the first voltage regulating unit 510, the second voltage regulating unit 520 or the third voltage regulating unit 530 in the voltage regulating module 500 to be disconnected from the circuit according to its output voltage to adjust the feedback voltage, and control the power supply module 100 to output the corresponding output voltage according to the adjusted feedback voltage through the main control chip 200, thereby realizing dynamic matching of the input and output voltage difference, so as to reduce the conduction loss and switching loss of the power device, avoid voltage difference loss, and improve product efficiency.
[0033] Option 2 refer to Figure 1 and Figure 4The first voltage regulating unit 510 includes a first switching transistor M22 and a fourth resistor R93. The second voltage regulating unit 520 includes a second switching transistor M23 and a fifth resistor R95. The third voltage regulating unit 530 includes a third switching transistor M24 and a sixth resistor R97. One end of the fourth resistor R93, the fifth resistor R95, and the sixth resistor R97 are all connected to the reference terminal of the reference voltage source 300. The other end of the fourth resistor R93 is connected to the drain D of the first switching transistor M22. The other end of the fifth resistor R95 is connected to the drain D of the second switching transistor M23. The other end of the sixth resistor R97 is connected to the drain D of the third switching transistor M24. The sources S of the first switching transistor M22, the second switching transistor M23, and the third switching transistor M24 are all grounded. The gates G of the first switching transistor M22, the second switching transistor M23, and the third switching transistor M24 are all connected to the output module 600.
[0034] This solution is based on Solution 1, and a first switch tube M22, a second switch tube M23, and a third switch tube M24 are respectively added to the first voltage regulating unit 510, the second voltage regulating unit 520, and the third voltage regulating unit 530. The gates G of the first switch tube M22, the second switch tube M23, and the third switch tube M24 are respectively connected to the first control terminal ON / OFF2, the second control terminal ON / OFF1, and the third control terminal ON / OFF3 of the output module 600, and the drains D of the first switch tube M22, the second switch tube M23, and the third switch tube M24 are respectively connected to control the levels of the fourth resistor R93, the fifth resistor R95, and the sixth resistor R97.
[0035] When the output module 600 has no output voltage or the output voltage is at a low voltage (e.g., 0V-9V), the first control terminal ON / OFF2, the second control terminal ON / OFF1, and the third control terminal ON / OFF3 of the output module 600 are in a high-impedance state, the first switch tube M22, the second switch tube M23, and the third switch tube M24 are turned on, and the corresponding connected fourth resistor R93, fifth resistor R95, and sixth resistor R97 have no effect on the reference voltage of the reference voltage source 300. The output voltage of the power supply module 100 is transmitted to the reference terminal of the reference voltage source 300 via the resistor R50, the seventh resistor R48, and the eighth resistor R49, and is fed back to the feedback pin of the main control chip 200 through the feedback module 400. The main control chip 200 controls the power supply module 100 to output a fixed voltage of 12-15V based on the feedback voltage received at the feedback pin. The specific voltage value can be selected according to specific needs.
[0036] When the output voltage of the output module 600 is at an intermediate voltage (such as 9-15V), the first control terminal ON / OFF2 of the output module 600 is in a low-level state, and the first switch tube M22 is disconnected to pull down the fourth resistor R93, so that the fourth resistor R93 is connected in parallel with the seventh resistor R48 and the eighth resistor R49 to adjust the reference voltage of the reference voltage source 300 and feedback it to the feedback pin of the main control chip 200 through the feedback module 400. The main control chip 200 controls the power supply module 100 to increase the voltage to 17-20V based on the feedback voltage received by the feedback pin. The specific increased voltage value can be adjusted by adjusting the resistance value of the first resistor R51.
[0037] When the output voltage of the output module 600 is at a high voltage (such as 15-21V), the second control terminal ON / OFF1 of the output module 600 is in a low level state, and the second switch tube M23 is disconnected to pull down the fifth resistor R95, so that the fifth resistor R95 is connected in parallel with the seventh resistor R48 and the eighth resistor R49 to adjust the reference voltage of the reference voltage source 300. The reference voltage is fed back to the feedback pin of the main control chip 200 through the feedback module 400. The main control chip 200 controls the power supply module 100 to increase the voltage to 20-22V based on the feedback voltage received by the feedback pin. The specific increased voltage value can be adjusted by adjusting the resistance value of the second resistor R54.
[0038] When the output voltage of the output module 600 is at a high voltage (such as 21-28V), the third control terminal ON / OFF3 of the output module 600 is in a low level state, and the third switch tube M24 is disconnected to pull down the sixth resistor R97, so that the sixth resistor R97 is connected in parallel with the seventh resistor R48 and the eighth resistor R49 to adjust the reference voltage of the reference voltage source 300 and feedback it to the feedback pin of the main control chip 200 through the feedback module 400. The main control chip 200 controls the power supply module 100 to increase the voltage to 28-30V based on the feedback voltage received by the feedback pin. The specific increased voltage value can be adjusted by adjusting the resistance value of the third resistor R52.
[0039] In one embodiment, reference Figure 2 and Figure 3 The feedback module 400 is a photocoupler, the input end of the feedback module 400 is the light emitting diode PC1A of the photocoupler, and the output end of the feedback module 400 is the phototransistor PC1B of the photocoupler.
[0040] In one embodiment, reference Figure 5 The output module 600 includes multiple output units, the voltage input terminals of the multiple output units are all connected to the voltage output terminals of the power supply module 100 , and the signal output terminal of one output unit is connected to the voltage regulation module 500 .
[0041] Specifically, refer to Figure 3 and Figure 5 The output module 600 includes a first output unit 610, a second output unit 620 and a third output unit 630. The voltage input ends of the first output unit 610, the second output unit 620 and the third output unit 630 are all connected to the voltage output end of the power supply module 100, the first control end ON / OFF2 of the first output unit 610 is connected to the first voltage regulating unit 510, the second control end ON / OFF1 of the first output unit 610 is connected to the second voltage regulating unit 520, and the third control end ON / OFF3 of the first output unit 610 is connected to the third voltage regulating unit 530. The voltage output ends of the first output unit 610, the second output unit 620 and the third output unit 630 are all used to connect to external devices.
[0042] refer to Figures 5 to 8 The first output unit 610 includes a first protocol chip U6 and an interface USB1. The voltage input terminal of the first protocol chip U6 is connected to the voltage output terminal of the power supply module 100, and the interface USB1 is connected to the voltage output terminal of the first protocol chip U6. The first control terminal ON / OFF2 of the first output unit 610 is the first control pin of the first protocol chip U6. The second control terminal ON / OFF1 of the first output unit 610 is the second control pin of the first protocol chip U6. The third control terminal ON / OFF3 of the first output unit 610 is the third control pin of the first protocol chip U6, that is, the first control pin of the first protocol chip U6. The control pin is connected to the first voltage regulating unit 510, the second control pin of the first protocol chip U6 is connected to the second voltage regulating unit 520, the third control pin of the first protocol chip U6 is connected to the third voltage regulating unit 530, the second protocol chip U7 and the third protocol chip U8 are both connected to the first protocol chip U6 through the I2C bus, the second output unit 620 includes the second protocol chip U7 and the interface USB2, the voltage input end of the second protocol chip U7 is connected to the voltage output end of the power supply module 100, the interface USB2 is connected to the voltage output end of the first protocol chip U7, and the third output unit 630 includes the third protocol chip U8.
[0043] like Figure 9 As shown, the present invention also provides a specific embodiment of a method for reducing negative resonant current.
[0044] A method to reduce negative resonant current, refer to Figure 9 The method for reducing the negative resonant current is implemented by the above-mentioned AHB multi-port charger, including the following steps: S1. When the output voltage of the output module changes from high to low, the output module controls multiple voltage regulating units in the voltage regulating module to be gradually disconnected at preset time intervals to gradually adjust the reference voltage of the reference voltage source; S2, feeding back the reference voltage to the main control chip through the feedback module; S3. The main control chip controls the power supply module according to the feedback voltage to gradually reduce the output voltage of the power supply module.
[0045] The reason for excessive negative resonant current is that when the power system is operating in steady state, the voltage across the resonant capacitor, Vc, is approximately nVo (n is the primary-to-secondary turns ratio of transformer T1A, and Vo is the output voltage of power supply module 100). When the product is hot-swapped, for example, when the output voltage jumps from 28V to 5V, the primary winding voltage of transformer T1A drops from nVo1 to nVo2. If the primary controller enters standby mode during output discharge, the lower clamping transistor will not be turned on again until standby mode ends. Because the Vc voltage cannot change suddenly, the voltage difference (nVo1-nVo2) is large, resulting in a large resonant current, Ic = (nVo1-nVo2)*C / Δt. This will generate a large current pulse and operating stress when the lower clamping transistor is turned on, thus affecting product reliability.
[0046] The formula Ic=(nVo1- nVo2)*C / Δt shows that adjusting the transformer T1A turns ratio n, the resonant capacitor capacitance C, the output voltage variation difference (nVo1- nVo2), and the variation time Δt can all change the magnitude of the negative resonant current. However, under normal circumstances, the transformer T1A turns ratio n and the resonant capacitor capacitance C cannot be changed after the product is manufactured. Therefore, the magnitude of the negative resonant current can be adjusted by changing the output voltage variation difference (nVo1- nVo2) and the variation time Δt.
[0047] Using the control principle of the above-mentioned AHB multi-port charger, it can be seen that when the output voltage of the output module 600 changes rapidly from high to low, for example, when it drops rapidly from 28V to 5V, the output voltage of the power supply module 100 (that is, the input voltage of the output module 600) can be slowly decreased, that is, the first control pin, the second control pin and the third control pin of the first protocol chip U6 are respectively controlled to disconnect the first resistor R51, the second resistor R54 and the third resistor R52 from the circuit in sequence at a preset time, or the first control pin, the second control pin and the third control pin of the first protocol chip U6 are respectively controlled to disconnect the first switch tube M22, the second switch tube M23 and the third switch tube M24 in sequence at a preset time, thereby disconnecting the corresponding fourth resistor R93, the fifth resistor R95 and the sixth resistor R97.
[0048] For example, when the input voltage of the output module 600 drops from 30V to 22V, then to 18V, and then to 13V, the first control pin, the second control pin, and the third control pin of the first protocol chip U6 respectively control the first resistor R51, the second resistor R54, and the third resistor R52 to be disconnected from the circuit in 500ms in sequence, thereby controlling the output voltage change difference (nVo1-nVo2) and the change time Δt of the power supply module 100 to achieve the function of reducing the negative resonant current, thereby facilitating the use of a larger resistance discharge resistor or not using a discharge resistor or using a smaller specification device to meet product needs, reduce power consumption, reduce costs, and improve work efficiency and reliability.
[0049] It should be noted that, according to actual needs, multiple voltage regulating units can be switched on and off once or multiple times in combination at expected time intervals to gradually reduce the output voltage of the power supply module.
[0050] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Those skilled in the art may modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present invention.
Claims
1. An AHB multi-port charger, characterized in that: include: A power supply module, a main control chip, a reference voltage source, a feedback module, a voltage regulating module and an output module, wherein the voltage input end of the power supply module is used to connect to an external AC power source, the voltage output end of the power supply module is connected to the voltage input end of the output module, and the voltage output end of the output module is used to connect to an external device. The voltage regulating module includes multiple parallel voltage regulating units, one end of each of the multiple voltage regulating units is connected to the output module, and the other end of each of the multiple voltage regulating units is connected to the reference end of the reference voltage source. The anode of the reference voltage source is grounded, the cathode of the reference voltage source is connected to the input end of the feedback module, the output end of the feedback module is connected to the feedback pin of the main control chip, and the control pin of the main control chip is connected to the power supply module.
2. The AHB multi-port charger according to claim 1, characterized in that: The voltage regulating module includes a first voltage regulating unit, a second voltage regulating unit and a third voltage regulating unit, one end of the first voltage regulating unit, the second voltage regulating unit and the third voltage regulating unit are all connected to the reference end of the reference voltage source, and the other ends of the first voltage regulating unit, the second voltage regulating unit and the third voltage regulating unit are all connected to the output module.
3. The AHB multi-port charger according to claim 2, characterized in that: The first voltage regulating unit is a first resistor, the second voltage regulating unit is a second resistor, and the third voltage regulating unit is a third resistor.
4. The AHB multi-port charger according to claim 2, characterized in that: The first voltage regulating unit includes a first switching tube and a fourth resistor, the second voltage regulating unit includes a second switching tube and a fifth resistor, and the third voltage regulating unit includes a third switching tube and a sixth resistor. One end of the fourth resistor, the fifth resistor, and the sixth resistor are all connected to the reference end of the reference voltage source, the other end of the fourth resistor is connected to the drain of the first switching tube, the other end of the fifth resistor is connected to the drain of the second switching tube, and the other end of the sixth resistor is connected to the drain of the third switching tube. The sources of the first switching tube, the second switching tube, and the third switching tube are all grounded, and the gates of the first switching tube, the second switching tube, and the third switching tube are all connected to the output module.
5. The AHB multi-port charger according to claim 2, characterized in that: The voltage regulating module further includes a seventh resistor and an eighth resistor, one end of each of the seventh resistor and the eighth resistor is connected to the reference end of the reference voltage source, and the other end of each of the seventh resistor and the eighth resistor is grounded.
6. The AHB multi-port charger according to claim 1, characterized in that: The feedback module is a photoelectric coupler, the input end of the feedback module is a light emitting diode of the photoelectric coupler, and the output end of the feedback module is a phototransistor of the photoelectric coupler.
7. The AHB multi-port charger according to claim 1, characterized in that: The output module includes multiple output units, the voltage input ends of the multiple output units are connected to the voltage output end of the power supply module, and the signal output end of one output unit is connected to the voltage regulation module.
8. The AHB multi-port charger according to claim 1, characterized in that: The output module includes a first output unit, a second output unit and a third output unit. The voltage input ends of the first output unit, the second output unit and the third output unit are all connected to the voltage output end of the power supply module, the control end of the first output unit is connected to the voltage regulating module, and the voltage output ends of the first output unit, the second output unit and the third output unit are all used to connect to external devices.
9. The AHB multi-port charger according to claim 8, characterized in that: The first output unit includes a first protocol chip, the second output unit includes a second protocol chip, and the third output unit includes a third protocol chip. The control end of the first protocol chip is connected to the voltage regulation module, and the second protocol chip and the third protocol chip are both connected to the first protocol chip via an I2C bus.
10. A method for reducing negative resonant current, characterized in that: The method is implemented by the AHB multi-port charger according to any one of claims 1 to 9, comprising the following steps: When the output terminal voltage of the output module changes from high to low, the output module controls the multiple voltage regulating units in the voltage regulating module to be gradually disconnected at preset time intervals, so as to gradually adjust the reference voltage of the reference voltage source; Feedback the reference voltage to the main control chip through the feedback module; The main control chip controls the power supply module according to the feedback voltage to gradually reduce the output voltage of the power supply module.