Smart fast charging power supply

Abstract

The present invention discloses an intelligent fast-charging power source, which includes an AC / DC step-down conversion circuit, a fast-charging control circuit, an optocoupler feedback circuit and a USB interface; the power input end of a discharge switch tube is connected to the output end of the low-voltage DC power, and the controlled end of the discharge switch tube is connected to the fast-charging controller; the fast-charging controller controls the output voltage of the AC / DC step-down conversion circuit through the optocoupler feedback circuit; the USB interface is respectively connected to the fast-charging controller and the power output end of the discharge switch tube, so as to control the discharge of the discharge switch tube through the fast-charging controller, so as to quickly charge the electronic device connected to the USB interface. Since the fast-charging controller can perform real-time conduction or cut-off control of the discharge switch tube according to the charging state of the electronic device, various abnormal situations in the fast-charging process of the electronic device can be handled in time to avoid causing serious accidents such as battery explosion and fire.

Description

Technical Field

[0001] The present invention relates to the technical field of power supplies, and in particular to an intelligent fast-charging power supply. Background Art

[0002] Existing electronic devices usually require fast charging to reduce the charging time. During the fast charging process, the power supply will adjust the output voltage and current according to the power supply requirements of the electronic device to provide a larger power supply for the electronic device to power the electronic device. Since the power supply power of the electronic device is relatively large. During the power supply process, the electronic device is prone to charging failure due to overcharging, short circuit or other reasons, and may even cause serious accidents such as battery explosion and fire.

[0003] In the prior art, fast charging power supplies generally only carry out fast charging protocol handshakes with electronic devices to provide fast charging power to electronic devices. Power supply fault detection and management are mainly handled by PWM power supply controllers. PWM power supply controllers generally only shut down the output of the power supply in the event of very serious circuit faults such as short circuits. In fast charging power supplies, PWM power supply controllers are increasingly unable to meet complex power supply safety requirements. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one object of the present invention is to provide an intelligent fast charging power supply.

[0005] To achieve the above object, a smart fast charging power supply according to an embodiment of the present invention includes:

[0006] An AC / DC step-down conversion circuit, which is used to rectify AC power into low-voltage DC power;

[0007] A fast charge control circuit, the fast charge control circuit comprising a fast charge controller and a discharge switch tube, the power input end of the discharge switch tube is connected to the output end of the low voltage direct current, and the controlled end of the discharge switch tube is connected to the fast charge controller;

[0008] An optocoupler feedback circuit, wherein the optocoupler feedback circuit is connected to the fast charge control circuit and the AC / DC buck conversion circuit respectively, and the fast charge controller controls the output voltage of the AC / DC buck conversion circuit through the optocoupler feedback circuit;

[0009] A USB interface, wherein the USB interface is respectively connected to the power output ends of the fast charge controller and the discharge switch tube, so as to control the discharge of the discharge switch tube through the fast charge controller to quickly charge the electronic device connected to the USB interface.

[0010] Further, according to an embodiment of the present invention, the discharge switch tube is a MOS transistor;

[0011] The source of the MOS transistor is connected to the low-voltage DC output end, the drain of the MOS transistor is connected to the USB interface, the gate of the MOS transistor is connected to the discharge control end of the fast charge controller through a first resistor R33, and the gate of the MOS transistor is also connected to the source of the MOS transistor through a second resistor R32.

[0012] Furthermore, according to an embodiment of the present invention, the fast charging control circuit also includes an output current detection circuit, and the output current detection circuit includes a current detection resistor R35, and the current detection resistor R35 is connected in series in the discharge circuit of the low-voltage direct current, and the two ends of the current detection resistor R35 are respectively connected to the current detection end of the fast charging controller, so that the fast charging controller can control the discharge switch tube to be turned on or off according to the detection current to perform overcurrent protection.

[0013] Furthermore, according to an embodiment of the present invention, the fast charge control circuit also includes an output voltage detection circuit, and the output voltage detection circuit includes a voltage detection resistor R31, one end of the voltage detection resistor R31 is connected to the output end of the low-voltage direct current, and the other end of the voltage detection resistor R31 is connected to the voltage detection end of the fast charge controller, so that the fast charge controller can control the discharge switch tube to be turned on or off according to the detection voltage to perform overvoltage protection.

[0014] Further, according to an embodiment of the present invention, the optocoupler feedback circuit includes:

[0015] Optocoupler U3, the anode terminal of the light-emitting diode of the optocoupler U3 is connected to the output terminal of the low-voltage direct current through a third resistor R27, the cathode terminal of the light-emitting diode of the optocoupler U3 is connected to the optocoupler terminal of the fast charging controller, the emitter terminal of the light-sensing transistor of the optocoupler U3 is connected to the reference ground, and the collector terminal of the light-sensing transistor of the optocoupler U3 is connected to the voltage feedback terminal of the AC / DC step-down conversion circuit.

[0016] Further, according to an embodiment of the present invention, the AC-DC step-down conversion circuit includes:

[0017] an AC-DC conversion circuit, the AC-DC conversion circuit being used to rectify the AC power into a first DC power;

[0018] A transformer module, the transformer module comprising a transformer, one end of a primary coil of the transformer being connected to an output end of the AC / DC conversion circuit, for transforming the DC power output by the AC / DC conversion circuit and outputting a second DC power;

[0019] A MOS switch tube, wherein the drain of the MOS switch tube is connected to the other side of the primary coil of the transformer, and the source of the MOS switch tube is connected to the reference ground;

[0020] A pulse modulation controller, wherein a pulse width modulation end of the pulse modulation controller is connected to the gate of the MOS switch tube, the pulse modulation controller is used to output a pulse width modulation signal, and perform pulse width modulation of the voltage of the primary coil of the transformer module through the MOS switch tube, and a voltage feedback end of the pulse modulation controller is connected to the collector end of the light sensing transistor of the optocoupler U3;

[0021] A synchronous rectification circuit is connected to the secondary coil of the transformer and is used for filtering the second direct current and outputting the stable low-voltage direct current.

[0022] Further, according to an embodiment of the present invention, the synchronous rectification circuit includes:

[0023] A rectifier switch tube Q2, wherein the source of the rectifier switch tube Q2 is connected to one end of the secondary coil of the transformer, and the drain of the rectifier switch tube Q2 is connected to the USB interface;

[0024] A synchronous rectifier U4, wherein a rectification control terminal of the synchronous rectifier U4 is connected to the gate of the rectification switch tube Q2, and a synchronous rectification detection terminal of the synchronous rectifier U4 is connected to the source of the rectification switch tube Q2 through a fourth resistor R41;

[0025] A first capacitor C10, one end of the first capacitor C10 is connected to the other end of the secondary coil of the transformer, and the other end of the first capacitor C10 is connected to the drain of the rectifier switch tube Q2.

[0026] Further, according to an embodiment of the present invention, the intelligent fast charging power supply further includes a primary coil current feedback circuit, and the primary coil current feedback circuit includes:

[0027] A fifth resistor R22, the MOS switch tube is connected to the reference ground through the fifth resistor R22; wherein, one end of the fifth resistor R22 is connected to the source of the MOS switch tube, the other end of the fifth resistor R22 is connected to the reference ground, and the one end of the fifth resistor R22 is also connected to the current detection end of the pulse modulation controller through the one end of the sixth resistor R17.

[0028] Further, according to an embodiment of the present invention, the voltage transformation module also includes: a spike absorption module, the spike absorption module includes a first diode D1, an eighth resistor R5 and a capacitor C5; the anode of the first diode D1 is connected to the drain of the MOS switch tube, the cathode of the first diode D1 is connected to the eighth resistor R5 and one end of the second capacitor C3 through the seventh resistor R7, and the other ends of the eighth resistor R5 and the second capacitor C3 are respectively connected to the one end of the primary coil of the transformer.

[0029] Further, according to one embodiment of the present invention, the intelligent fast charging power supply also includes an auxiliary power supply module, and the auxiliary power supply module includes:

[0030] a second diode D2, wherein an anode of the second diode D2 is connected to an auxiliary coil of the transformer via a resistor R9;

[0031] A voltage transformation module, wherein the input end of the voltage transformation module is connected to the cathode of the second diode D2, and the output end of the voltage transformation module is connected to the power supply end of the pulse modulation controller.

[0032] The intelligent fast charging power supply provided in the embodiment of the present invention is connected to the output end of the low-voltage direct current through the power input end of the discharge switch tube, and the controlled end of the discharge switch tube is connected to the fast charging controller; the optocoupler feedback circuit is respectively connected to the fast charging control circuit and the AC / DC buck conversion circuit, and the fast charging controller controls the output voltage of the AC / DC buck conversion circuit through the optocoupler feedback circuit; the USB interface is respectively connected to the fast charging controller and the power output end of the discharge switch tube, so as to control the discharge of the discharge switch tube through the fast charging controller, so as to quickly charge the electronic device connected to the USB interface. Since the fast charging controller can perform real-time conduction or cutoff control of the discharge switch tube according to the charging status of the electronic device, various abnormal situations in the fast charging process of the electronic device can be handled in time to avoid causing serious accidents such as battery explosion and fire. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A block diagram of the structure of an intelligent fast-charging power supply provided by an embodiment of the present invention;

[0034] Figure 2 A schematic diagram of the structure of a smart fast charging power supply circuit provided in an embodiment of the present invention.

[0035] Reference numerals:

[0036] AC-DC conversion circuit 10;

[0037] Peak absorption circuit 20;

[0038] Transformation module 30;

[0039] Synchronous rectification circuit 40;

[0040] Fast charge control circuit 50;

[0041] USB interface 60;

[0042] Switching tube 70;

[0043] Auxiliary power supply circuit 80;

[0044] Pulse modulator 90;

[0045] Voltage feedback circuit 11;

[0046] Primary coil current feedback circuit 13;

[0047] Driving circuit 14.

[0048] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0049] In order to make those skilled in the art better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0050] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0051] See also Figure 1 and Figure 2 An embodiment of the present invention provides an intelligent fast charging power supply, including: the AC / DC step-down conversion circuit includes: an AC / DC conversion circuit 10, a transformer module 30, a MOS switch tube 70, a pulse modulation controller and a synchronous rectification circuit 40, the AC / DC conversion circuit 10 is used to rectify AC power into a first DC power; the AC power can be AC ​​power from the mains, and the AC / DC conversion circuit 10 can rectify the AC power from the mains into high-voltage DC power and output it to the transformer module 30.

[0052] The transformer module 30 includes a transformer, one end of the primary coil of the transformer is connected to the output end of the AC / DC conversion circuit 10, and is used to transform the DC power output by the AC / DC conversion circuit 10 and output a second DC power; the drain of the MOS switch tube 70 is connected to the other end of the primary coil of the transformer, and the source of the MOS switch tube 70 is connected to the reference ground; since the other end of the primary coil of the transformer is connected to the reference ground through the MOS switch tube 70. In this way, the current on the primary coil can be turned on or off by adjusting the ratio of on / off. Thus, PWM modulation of the primary coil is realized, and the first DC power is modulated into pulsating DC power, which is transformed by the transformer and output from the secondary coil of the transformer.

[0053] The pulse width modulation end of the pulse modulation controller U1 is connected to the gate of the MOS switch tube 70. The pulse modulation controller U1 is used to output the pulse width modulation signal PWM, and perform pulse width modulation of the voltage of the primary coil of the transformer module 30 through the MOS switch tube 70. The voltage feedback end of the pulse modulation controller U1 is connected to the collector end of the photosensitive transistor of the optocoupler U3; the pulse modulation controller U1 can adjust the pulse width of the output pulse width modulation signal PWM according to the feedback signal of the optocoupler U3. In this way, the low-voltage direct current can be adjusted to the charging voltage value of the electronic device to achieve fast charging of the electronic device. After the low-voltage direct current is adjusted to the charging voltage value of the electronic device, the stability of the output voltage is guaranteed by adjusting the PWM pulse width in real time.

[0054] The synchronous rectification circuit 40 is connected to the secondary coil of the transformer, and is used to filter the second DC power and output the stable low-voltage DC power. The transformed pulse DC power can be output through the secondary coil of the transformer, and filtered through the output filter circuit, and stable low-voltage DC power can be provided to the outside, thereby powering the electronic equipment.

[0055] See also Figure 2 The synchronous rectification circuit 40 comprises: a rectification switch tube Q2 (70), a synchronous rectifier U4 and a first capacitor C10, wherein the source of the rectification switch tube Q2 (70) is connected to one end of the secondary coil of the transformer, and the drain of the rectification switch tube Q2 (70) is connected to the USB interface 60; the rectification switch tube Q2 (70) is connected in series to the output circuit of the low-voltage direct current to rectify and output the pulsating direct current of the secondary coil of the transformer to avoid current backflow.

[0056] The rectification control terminal of the synchronous rectifier U4 is connected to the gate of the rectification switch tube Q2 (70), and the synchronous rectification detection terminal of the synchronous rectifier U4 is connected to the source of the rectification switch tube Q2 (70) through the fourth resistor R41; the synchronous rectification detection terminal of the synchronous rectifier U4 is connected to one end of the secondary coil of the transformer through the fourth resistor R41. In this way, the voltage of the secondary coil of the transformer can be detected, and a control signal can be output through the rectification control terminal (5) of the synchronous rectifier U4 to perform rectification control on the rectification switch tube Q2 (70).

[0057] One end of the first capacitor C10 is connected to the other end of the secondary coil of the transformer, and the other end of the first capacitor C10 is connected to the drain of the rectifier switch tube Q2 (70). The pulsating direct current output by the rectifier switch tube Q2 (70) can be stabilized and filtered by the first capacitor C10 to output stable low-voltage direct current, thereby powering the electronic equipment at the back end.

[0058] See also Figure 2 , the intelligent fast charging power supply also includes a primary coil current feedback circuit 13, and the primary coil current feedback circuit 13 includes: a fifth resistor R22, and the MOS switch tube Q1 is connected to the reference ground through the fifth resistor R22; wherein, one end of the fifth resistor R22 is connected to the source of the MOS switch tube Q1, and the other end of the fifth resistor R22 is connected to the reference ground, and the one end of the fifth resistor R22 is also connected to the current detection end of the pulse modulation controller U1 through the one end of the sixth resistor R17. The fifth resistor R22 is connected in series with the MOS switch tube Q1 in the charging and discharging circuit of the primary coil of the transformer. In this way, the current of the primary coil can be detected through the fifth resistor R22. The detection resistor can be set to multiple, such as Figure 2 The current sampled from the fifth resistor R22 is fed back to the current detection terminal of the pulse modulation controller U1 through the sixth resistor R17, so that the pulse modulation controller U1 can obtain the current value of the primary coil and adjust the output PWM pulse width according to the current value to detect the short-circuit state of the primary coil. This allows short-circuit protection and output voltage regulation and control.

[0059] The transformer module 30 also includes: a peak absorption module, which includes a first diode D1, an eighth resistor R5 and a second capacitor C3; the anode of the first diode D1 is connected to the drain of the MOS switch tube Q1, and the cathode of the first diode D1 is connected to the eighth resistor R5 and one end of the second capacitor C3 through the seventh resistor R7, respectively, and the other ends of the eighth resistor R5 and the second capacitor C3 are respectively connected to the one end of the primary coil of the transformer. At the moment when the switch tube Q1 is turned off, since the current of the primary coil cannot produce a sudden change, a spike pulse signal will appear at the drain of the switch tube 70. The strong spike pulse signal may damage the MOS switch tube Q1, causing the circuit to fail. In addition, the spike pulse signal is the main source of interference. Therefore, it is necessary to absorb the spike signal of the primary coil. The first diode D1, the eighth resistor R5 and the second capacitor C3 form a spike absorption circuit. After the switch tube Q1 is turned off, the spike signal generated by the primary coil absorbs the spike signal through the first diode D1, the eighth resistor R5 and the second capacitor C3.

[0060] See also Figure 2 The intelligent fast charging power supply further includes an auxiliary power supply module, which includes: a second diode D2 and a transformer module U2 (30), wherein the anode of the second diode D2 is connected to the auxiliary coil of the transformer via a resistor R9; the pulsating DC of the auxiliary coil can be rectified and outputted via the second diode D2. The pulsating DC of the auxiliary coil is rectified and filtered by a capacitor and then outputted to the second diode D2.

[0061] The input terminal IN of the transformer module U2 (30) is connected to the cathode of the second diode D2, and the output terminal VCC of the transformer module U2 (30) is connected to the power supply terminal of the pulse modulation controller U1. The power output and sorted by the auxiliary coil is transformed by the transformer module U2 (30) and output to the power supply terminal of the pulse modulation controller U1 to supply power to the pulse modulation controller U1.

[0062] The above are only embodiments of the present invention, but they do not limit the patent scope of the present invention. Although the present invention is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments, or replace some of the technical features with equivalent ones. Any equivalent structure made by using the contents of the present invention specification and drawings, directly or indirectly used in other related technical fields, is also within the scope of patent protection of the present invention.

[0063] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0064] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and intent of the present invention.

Claims

1. A smart fast charging power source, characterized in that: include: An AC / DC step-down conversion circuit, which is used to rectify AC power into low-voltage DC power; A fast charge control circuit, the fast charge control circuit comprising a fast charge controller and a discharge switch tube, the power input end of the discharge switch tube is connected to the output end of the low voltage direct current, and the controlled end of the discharge switch tube is connected to the fast charge controller; An optocoupler feedback circuit, wherein the optocoupler feedback circuit is connected to the fast charge control circuit and the AC / DC buck conversion circuit respectively, and the fast charge controller controls the output voltage of the AC / DC buck conversion circuit through the optocoupler feedback circuit; A USB interface, wherein the USB interface is connected to the power output terminals of the fast charge controller and the discharge switch tube respectively, so as to control the discharge of the discharge switch tube through the fast charge controller to quickly charge the electronic device connected to the USB interface; in, The optocoupler feedback circuit comprises: an optocoupler (U3), wherein an anode end of a light-emitting diode of the optocoupler (U3) is connected to an output end of the low-voltage direct current via a third resistor (R27), a cathode end of a light-emitting diode of the optocoupler (U3) is connected to an optocoupler end of the fast charge controller, an emitter end of a light-sensing transistor of the optocoupler (U3) is connected to a reference ground, and a collector end of the light-sensing transistor of the optocoupler (U3) is connected to a voltage feedback end of an AC / DC step-down conversion circuit; in, The AC / DC step-down conversion circuit comprises: an AC-DC conversion circuit, the AC-DC conversion circuit being used to rectify the AC power into a first DC power; A transformer module, the transformer module comprising a transformer, one end of a primary coil of the transformer being connected to an output end of the AC / DC conversion circuit, for transforming the DC power output by the AC / DC conversion circuit and outputting a second DC power; A MOS switch tube, wherein the drain of the MOS switch tube is connected to the other side of the primary coil of the transformer, and the source of the MOS switch tube is connected to the reference ground; a pulse modulation controller, wherein a pulse width modulation end of the pulse modulation controller is connected to the gate of the MOS switch tube, the pulse modulation controller is used to output a pulse width modulation signal and perform pulse width modulation of the voltage of the primary coil of the transformer module through the MOS switch tube, and a voltage feedback end of the pulse modulation controller is connected to the collector end of the light sensing transistor of the optocoupler (U3); A synchronous rectification circuit is connected to the secondary coil of the transformer and is used for filtering the second direct current and outputting the stable low-voltage direct current.

2. The intelligent fast charging power source according to claim 1, characterized in that: The discharge switch tube is a MOS transistor; The source of the MOS transistor is connected to the low-voltage direct current output terminal, the drain of the MOS transistor is connected to the USB interface, the gate of the MOS transistor is connected to the discharge control terminal of the fast charge controller through a first resistor (R33), and the gate of the MOS transistor is also connected to the source of the MOS transistor through a second resistor (R32).

3. The intelligent fast charging power source according to claim 1, characterized in that: The fast charge control circuit also includes an output current detection circuit, which includes a current detection resistor (R35). The current detection resistor (R35) is connected in series in the discharge circuit of the low-voltage direct current, and the two ends of the current detection resistor (R35) are respectively connected to the current detection ends of the fast charge controller, so that the fast charge controller controls the discharge switch tube to be turned on or off according to the detection current to perform overcurrent protection.

4. The intelligent fast charging power source according to claim 1, characterized in that: The fast charge control circuit also includes an output voltage detection circuit, which includes a voltage detection resistor (R31), one end of which is connected to the output end of the low-voltage direct current, and the other end of which is connected to the voltage detection end of the fast charge controller, so that the fast charge controller can control the discharge switch tube to be turned on or off according to the detection voltage to perform overvoltage protection.

5. The intelligent fast charging power source according to claim 1, characterized in that: The synchronous rectification circuit comprises: A rectifier switch tube (Q2), wherein a source of the rectifier switch tube (Q2) is connected to one end of the secondary coil of the transformer, and a drain of the rectifier switch tube (Q2) is connected to the USB interface; A synchronous rectifier (U4), wherein a rectification control terminal of the synchronous rectifier (U4) is connected to the gate of the rectification switch tube (Q2), and a synchronous rectification detection terminal of the synchronous rectifier (U4) is connected to the source of the rectification switch tube (Q2) via a fourth resistor (R41); A first capacitor (C10), one end of the first capacitor (C10) is connected to the other end of the secondary coil of the transformer, and the other end of the first capacitor (C10) is connected to the drain of the rectifier switch tube (Q2).

6. The intelligent fast charging power source according to claim 1, characterized in that: It also includes a primary coil current feedback circuit, the primary coil current feedback circuit including: A fifth resistor (R22), the MOS switch tube is connected to the reference ground through the fifth resistor (R22); wherein one end of the fifth resistor (R22) is connected to the source of the MOS switch tube, the other end of the fifth resistor (R22) is connected to the reference ground, and the one end of the fifth resistor (R22) is also connected to the current detection end of the pulse modulation controller through the one end of the sixth resistor (R17).

7. The intelligent fast charging power source according to claim 1, characterized in that: The voltage transformation module further comprises: a peak absorption module, the peak absorption module comprising a first diode (D1), an eighth resistor (R5) and a second capacitor (C3); an anode of the first diode (D1) is connected to a drain of the MOS switch tube, a cathode of the first diode (D1) is connected to one end of the eighth resistor (R5) and the second capacitor (C3) through a seventh resistor (R7), and the other ends of the eighth resistor (R5) and the second capacitor (C3) are respectively connected to the one end of the primary coil of the transformer.

8. The intelligent fast charging power source according to claim 1, characterized in that: Also includes an auxiliary power supply module, the auxiliary power supply module includes: a second diode (D2), wherein an anode of the second diode (D2) is connected to an auxiliary coil of the transformer via a resistor R9; A voltage conversion module, wherein the input end of the voltage conversion module is connected to the cathode of the second diode (D2), and the output end of the voltage conversion module is connected to the power supply end of the pulse modulation controller.

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