Charging switching circuit and charger thereof

Abstract

The utility model relates to the technical field of power supplies, in particular to a charging switching circuit and a charger thereof. Comprising a step-down control chip, a main control chip, a change-over switch, a quick charge control chip, a HUB control chip and a USB interface, the main control chip comprises a current detection pin connected with the USB interface, a voltage input end of the USB interface is connected with a voltage output end of the voltage reduction control chip, a DM pin and a DP pin of the USB interface are both connected with an input end of the change-over switch, a first output end of the change-over switch is connected with the fast charge control chip, a second output end of the change-over switch is connected with the HUB control chip, and the HUB control chip is connected with the USB interface. The enabling end of the change-over switch is connected with the output end of the main control chip, in the embodiment, the current of the USB interface is detected through the current detection pin so as to output a corresponding level to control the switching module to automatically switch the DM pin and the DP pin of the USB interface to the quick charge control chip or the HUB control chip, and the USB interface can be quickly charged. Automatic switching between fast charging and slow charging according to the device connected to the USB interface is realized, and the charging efficiency is effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply, in particular to a charging switching circuit and a charger thereof. Background Art

[0002] A multi-port USB charger is a two-in-one product with both charging and hub functions. Currently, the circuit design of such products on the market usually connects the DP and DM pins on the USB2.0 interface with hub data transmission function directly to the DP and DM pins of the hub control chip, respectively, to achieve USB2.0 data transmission. Due to the limitations of the hub control chips currently on the market, their DP and DM pins only support the basic BC1.2 charging protocol. As a result, devices connected to the USB2.0 interface can only support BC1.2 charging protocol charging, resulting in a very slow charging speed and inability to achieve fast charging mode, resulting in a very poor charging experience for users.

[0003] Therefore, it is very important for those skilled in the art to design a charging switching circuit and a charger thereof that can automatically switch the charging mode according to the connected device. Utility Model Content

[0004] The technical problem to be solved by the embodiments of the present invention is to provide a charging switching circuit and a charger thereof that can automatically switch the charging mode according to the connected device, so as to solve the problem in the prior art that devices connected to the USB2.0 interface can only support BC1.2 charging protocol charging when charging, resulting in a very slow charging speed.

[0005] The utility model discloses a charging switching circuit, which includes: a step-down control chip, a main control chip, a switching switch, a fast charging control chip, a HUB control chip and a USB interface; the main control chip includes a current detection pin connected to the USB interface, the voltage input end of the USB interface is connected to the voltage output end of the step-down control chip, the DM pin and DP pin of the USB interface are both connected to the input end of the switching switch, the first output end of the switching switch is connected to the fast charging control chip, the second output end of the switching switch is connected to the HUB control chip, and the enable end of the switching switch is connected to the output end of the main control chip, so as to switch the DM pin and DP pin of the USB interface to the fast charging control chip or the HUB control chip according to the current detected by the main control chip.

[0006] Optionally, a sampling resistor is provided on the USB interface, and a current detection pin of the main control chip is connected to the sampling resistor for current detection.

[0007] Optionally, the USB interface includes a data transmission pin, and the data transmission pin of the USB interface is connected to the HUB control chip through the switch.

[0008] Optionally, the input end of the switching switch includes a D+ pin and a D- pin, the D+ pin of the switching switch is connected to the DP pin of the USB interface through the switching switch, and the D- pin of the switching switch is connected to the DM pin of the USB interface.

[0009] Optionally, the first output end of the switching switch includes an HSD1- pin and an HSD1+ pin, the HSD1- pin of the switching switch is connected to the DM pin of the fast charging control chip, and the HSD1+ pin of the switching switch is connected to the DP pin of the fast charging control chip.

[0010] Optionally, the second output end of the switch includes an HSD2- pin and an HSD2+ pin, the HSD2- pin of the switch is connected to the DM pin of the HUB control chip, and the HSD2+ pin of the switch is connected to the DP pin of the HUB control chip.

[0011] Optionally, a protection resistor is provided between the enable terminal of the switch and the output terminal of the main control chip.

[0012] Optionally, a pull-down resistor is further provided on the enable end of the switch.

[0013] Optionally, a filter circuit is provided between the voltage output terminal of the step-down control chip and the voltage input terminal of the USB interface.

[0014] In order to solve the problems existing in the prior art, the present invention also provides a charger, wherein the charger includes a body and a circuit board, the circuit board is arranged in the body, and the charging switching circuit as described above is arranged on the circuit board.

[0015] Compared with the prior art, the beneficial effect of the charging switching circuit provided by the embodiment of the present invention is that: by designing a charging switching circuit, including a step-down control chip, a main control chip, a switching switch, a fast charging control chip, a HUB control chip and a USB interface; the main control chip is configured with a current detection pin for detecting the current of the USB interface, the DM pin and DP pin of the USB interface are both connected to the input end of the switching switch, the first output end of the switching switch is connected to the fast charging control chip, and the second output end of the switching switch is connected to the HUB control chip. By detecting the current of the USB interface, the switching switch can be controlled to automatically switch the DM pin and DP pin of the USB interface to the fast charging control chip or the HUB control chip, thereby realizing automatic switching between fast charging and slow charging, and effectively improving the user experience. 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:

[0017] Figure 1 This is a module block diagram of a charging switching circuit provided by an embodiment of the present utility model;

[0018] Figure 2 1 is a circuit diagram of a charging switching circuit provided by an embodiment of the present utility model;

[0019] Figure 3 This is a module block diagram of the charger provided by an embodiment of the present utility model. DETAILED DESCRIPTION

[0020] 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, a detailed description of the preferred embodiments of the present utility model will be given.

[0021] like Figures 1 to 3 As shown, the utility model provides a specific embodiment of a charging switching circuit.

[0022] A charging switching circuit is used in a charger with charging function and HUB function. Figure 1 and Figure 2 The charging switching circuit includes a step-down control chip 100, a main control chip 200, a switching switch 300, a fast charging control chip 400, a HUB control chip 500 and a USB interface 600; the voltage input end of the USB interface 600 is connected to the voltage output end of the step-down control chip 100 to obtain the charging voltage; the main control chip 200 includes a current detection pin connected to the USB interface 600 for detecting the current flowing through the USB interface 600.

[0023] Among them, reference Figure 1 and Figure 2 The DM pin and DP pin of the USB interface 600 are both connected to the input end of the switching switch 300, the first output end of the switching switch 300 is connected to the fast charging control chip 400, the second output end of the switching switch is connected to the HUB control chip 500, and the enable end of the switching switch 300 is connected to the output end of the main control chip 200, so as to switch the DM pin and DP pin of the USB interface 600 to the fast charging control chip 400 or the HUB control chip 500 according to the current detected by the main control chip 200.

[0024] Specifically, refer to Figure 1 and Figure 2The step-down control chip 100 is used to adjust the output voltage and reduce the input voltage of the charger to the output voltage required for charging. The step-down control chip 100 can monitor the output voltage and adjust the duty cycle of the switch tube as needed to keep the output voltage stable; the voltage output end of the step-down control chip 100 is connected to the voltage input end of the USB interface 600 to power external devices.

[0025] Further, refer to Figure 1 and Figure 2 The main control chip 200 is equipped with a current detection pin, which is connected to the USB interface 600. The USB interface 600 is provided with a sampling resistor R1. The current detection pin of the main control chip 200 includes a PA6 pin and a PA7 pin. Among them, the PA6 pin of the main control chip 200 is connected to one end of the sampling resistor R1, and the PA7 pin of the main control chip 200 is connected to the other end of the sampling resistor R1.

[0026] Further, refer to Figure 1 and Figure 2 The fast charging control chip 400 is compatible with the fast charging protocol to achieve higher charging speed and efficiency; the HUB control chip 500 is used to manage USB data transmission. The HUB control chip 500 supports BC1.2 DCP mode and can realize BC1.2 protocol slow charging of connected devices.

[0027] Further, refer to Figure 1 and Figure 2 The input end of the switching switch 300 is connected to the DM pin and DP pin of the USB interface 600, the first output end of the switching switch 300 is connected to the fast charging control chip 400, the second output end of the switching switch is connected to the HUB control chip 500, and the enable end S of the switching switch 300 is connected to the output end PA1 of the main control chip 200. The switching switch 300 is configured to switch the DM pin and DP pin of the USB interface 600 to the fast charging control chip 400 when its enable end is at a low level, and to switch the DM pin and DP pin of the USB interface 600 to the HUB control chip 500 when its enable end S is at a high level.

[0028] When an external device is connected to the USB interface 600, the external device will draw current from the USB interface 600. The main control chip 200 can detect the current flowing through the USB interface 600 by obtaining the current across the sampling resistor R1. Since the current drawn by devices such as hard disks, U disks, and mice known in the industry will not exceed 0.5A, the main control chip 200 can determine that the device connected to the USB interface 600 is a charging device such as a mobile phone through the current value detected by the main control chip 200. When it is determined that the device connected to the USB interface 600 is a charging device such as a mobile phone, the main control chip The chip 200 will output a low level to the enable end of the switching switch 300, and the switching switch 300 will switch the DM pin and DP pin of the USB interface 600 to the fast charging control chip 400 to achieve fast charging of charging devices such as mobile phones; when it is determined that the device connected to the USB interface 600 is a hard disk, U disk, mouse and other devices, the main control chip 200 will output a high level to the enable end of the switching switch 300, and the switching switch 300 will switch the DM pin and DP pin of the USB interface 600 to the HUB control chip 500 for data transmission and slow charging.

[0029] In the prior art, a two-in-one charger with both charging and HUB functions usually connects the DP pin and DM pin on the corresponding USB2.0 interface with the HUB data transmission function directly to the DP pin and DM pin of the HUB control chip, respectively, to achieve USB2.0 data transmission. Since the DP pin and DM pin of the HUB control chip on the market only support the basic BC1.2 charging protocol, the device connected to the USB2.0 interface can only support BC1.2 charging protocol charging during charging, and fast charging cannot be achieved.

[0030] In this embodiment, a charging switching circuit is designed, including a step-down control chip 100, a main control chip 200, a switching switch 300, a fast charging control chip 400, a HUB control chip 500 and a USB interface 600; the main control chip 200 is configured with a current detection pin for detecting the current of the USB interface 600, the DM pin and DP pin of the USB interface 600 are both connected to the input end of the switching switch 300, the first output end of the switching switch 300 is connected to the fast charging control chip 400, and the second output end of the switching switch is connected to the HUB control chip 500. By detecting the current of the USB interface 600, the switching switch can be controlled to automatically switch the DM pin and DP pin of the USB interface 600 to the fast charging control chip 400 or the HUB control chip 500, thereby realizing automatic switching between fast charging and slow charging, effectively improving the user experience.

[0031] In one embodiment, reference Figure 1The USB interface 600 includes a data transmission pin 610 , and the data transmission pin 610 of the USB interface 600 is connected to the HUB control chip 500 .

[0032] Specifically, refer to Figure 1 and Figure 2 The data transmission pins 610 of the USB interface 600 specifically include SSRX- pin, SSRX+ pin, SSTX- pin and SSTX+ pin. The SSRX- pin, SSRX+ pin, SSTX- pin and SSTX+ pin of the USB interface 600 are all connected to the input and output pins of the HUB control chip 500 for HUB data transmission.

[0033] In one embodiment, reference Figure 1 and Figure 2 The input end of the switch 300 includes a D+ pin and a D- pin. The D+ pin of the switch 300 is connected to the DP pin of the USB interface 600, and the D- pin of the switch 300 is connected to the DM pin of the USB interface 600.

[0034] Specifically, refer to Figure 1 and Figure 2 The first output end of the switching switch 300 includes an HSD1- pin and an HSD1+ pin. The HSD1- pin of the switching switch 300 is connected to the DM pin of the fast charging control chip 400, and the HSD1+ pin of the switching switch 300 is connected to the DP pin of the fast charging control chip 400. The second output end of the switching switch 300 includes an HSD2- pin and an HSD2+ pin. The HSD2- pin of the switching switch 300 is connected to the DM pin of the HUB control chip 500, and the HSD2+ pin of the switching switch 300 is connected to the DP pin of the HUB control chip 500.

[0035] When it is determined that the device connected to the USB interface 600 is a charging device such as a mobile phone, the main control chip 200 will output a low level to the enable end of the switching switch 300, and the D+ pin and D- pin of the switching switch 300 will be turned on with the HSD1+ pin and HSD1- pin of the switching switch 300 respectively, so as to switch the DM pin and DP pin of the USB interface 600 to the DM pin and DP pin of the fast charging control chip 400, so as to achieve fast charging of charging devices such as mobile phones; when it is determined that the device connected to the USB interface 600 is a hard disk, U disk, mouse or other device, the main control chip 200 will output a high level to the enable end of the switching switch 300, and the D+ pin and D- pin of the switching switch 300 will be turned on with the HSD2+ pin and HSD2- pin of the switching switch 300 respectively, so as to switch the DM pin and DP pin of the USB interface 600 to the DM pin and DP pin of the HUB control chip 500 for data transmission and slow charging.

[0036] In one embodiment, reference Figure 2 A protection resistor R8 and a pull-down resistor R9 are provided between the enable terminal of the switch 300 and the output terminal of the main control chip 200 .

[0037] Specifically, refer to Figure 2 The enable terminal is used to control the on and off of the switching switch 300. By setting a protection resistor R8 at the enable terminal, it can ensure that the signal at the enable terminal remains in a known state when no external signal is connected, thereby avoiding drift and interference of the enable signal. The protection resistor R8 can also limit the current at the enable terminal to prevent excessive current from damaging the circuit or device, and play a certain degree of overcurrent protection role.

[0038] Further, refer to Figure 2 When the enable terminal is not connected to the signal source, the pull-down resistor R9 can pull the enable terminal to a certain level to avoid the enable terminal being in an undefined floating state, thereby improving the stability and reliability of the system.

[0039] In one embodiment, reference Figure 2 A filter circuit 110 is provided between the voltage output terminal of the step-down control chip 100 and the voltage input terminal of the USB interface 600 .

[0040] Specifically, refer to Figure 2 The filter circuit 110 is used to filter out noise and interference signals to prevent unnecessary high-frequency or low-frequency signals from damaging or interfering with components. It not only provides protection for circuit components, but also reduces signal distortion during transmission to maintain signal stability and accuracy.

[0041] like Figure 3 As shown, the utility model also provides a specific embodiment of a charger.

[0042] A charger, reference Figure 3 The charger includes a body 10 and a circuit board 20. The circuit board 20 is arranged in the body 10. The charging switching circuit 30 as described above is arranged on the circuit board 20.

[0043] 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 replace some of the technical features therein with equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A charging switching circuit, characterized in that: include: A step-down control chip, a main control chip, a switching switch, a fast charging control chip, a HUB control chip and a USB interface; the main control chip includes a current detection pin connected to the USB interface, the voltage input end of the USB interface is connected to the voltage output end of the step-down control chip, the DM pin and DP pin of the USB interface are both connected to the input end of the switching switch, the first output end of the switching switch is connected to the fast charging control chip, the second output end of the switching switch is connected to the HUB control chip, and the enable end of the switching switch is connected to the output end of the main control chip, so as to switch the DM pin and DP pin of the USB interface to the fast charging control chip or the HUB control chip according to the current detected by the main control chip.

2. The charging switching circuit according to claim 1, wherein: The USB interface is provided with a sampling resistor, and the current detection pin of the main control chip is connected to the sampling resistor for current detection.

3. The charging switching circuit according to claim 1, wherein: The USB interface includes a data transmission pin, and the data transmission pin of the USB interface is connected to the HUB control chip through the switch.

4. The charging switching circuit according to claim 1, wherein: The input end of the switching switch includes a D+ pin and a D- pin. The D+ pin of the switching switch is connected to the DP pin of the USB interface through the switching switch, and the D- pin of the switching switch is connected to the DM pin of the USB interface.

5. The charging switching circuit according to claim 1, wherein: The first output end of the switching switch includes an HSD1- pin and an HSD1+ pin. The HSD1- pin of the switching switch is connected to the DM pin of the fast charging control chip, and the HSD1+ pin of the switching switch is connected to the DP pin of the fast charging control chip.

6. The charging switching circuit according to claim 1, wherein: The second output end of the switch includes an HSD2- pin and an HSD2+ pin. The HSD2- pin of the switch is connected to the DM pin of the HUB control chip, and the HSD2+ pin of the switch is connected to the DP pin of the HUB control chip.

7. The charging switching circuit according to claim 1, wherein: A protection resistor is provided between the enable end of the switching switch and the output end of the main control chip.

8. The charging switching circuit according to claim 1, wherein: A pull-down resistor is also provided on the enable end of the switch.

9. The charging switching circuit according to claim 1, wherein: A filter circuit is provided between the voltage output terminal of the step-down control chip and the voltage input terminal of the USB interface.

10. A charger, characterized in that: The charger includes a body and a circuit board. The circuit board is arranged in the body, and the charging switching circuit according to any one of claims 1 to 9 is arranged on the circuit board.

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