An offline charging circuit for nickel-metal hydride button batteries for hearing aids

Abstract

The present invention discloses an offline charging circuit for nickel-metal hydride button batteries for hearing aids, belonging to the technical field of hearing aid power supplies. An external power supply is connected to two input interfaces of a charging management chip, and two output interfaces of the charging management chip are connected to a first main charging position and a second main charging position, respectively. An external adjustment tube VT1 and an external adjustment tube VT2 are connected between the external power supply and the two input interfaces of the charging management chip, respectively. The first main charging position is connected to a first sampling circuit and a first discharge circuit, and the second main charging position is connected to a second sampling circuit and a second discharge circuit. The first sampling circuit, the first discharge circuit, the second sampling circuit, and the second discharge circuit are all connected to a main control microcontroller. The present invention can automatically pre-charge and condition a deeply depleted battery and automatically stop charging when charging is complete, effectively eliminating the memory effect and extending the battery life.

Description

Technical Field

[0001] The present invention relates to the technical field of hearing aid power supplies, and in particular to an offline charging circuit for a nickel-hydrogen button battery for a hearing aid. Background Art

[0002] Hearing aids are devices that help improve hearing. China sees over 1.5 million new hearing aid users annually, and the number globally exceeds 15 million, representing a massive market. Modern hearing aids are becoming increasingly smaller and more miniaturized. Furthermore, as important hearing aids, hearing aids are used frequently and for extended periods of time, requiring batteries to discharge continuously over extended periods of time. To meet volume requirements, hearing aid batteries are typically button cells. To meet these requirements, the battery's capacity is higher, necessitating the addition of a rechargeable battery.

[0003] The following problems exist in the existing technology: improper use of conventional rechargeable batteries such as nickel-cadmium batteries, nickel-metal hydride batteries, lead-acid batteries, etc. will produce varying degrees of memory effect, resulting in problems such as failure to charge or insufficient charging, which shortens the battery life. This problem needs to be solved urgently. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the purpose of the present invention is to provide an offline charging circuit for nickel-metal hydride button batteries for hearing aids, which can automatically pre-charge and condition deeply depleted batteries and automatically stop charging when charging is complete, effectively eliminating the memory effect and extending the battery life.

[0005] A hearing aid nickel-metal hydride button battery offline charging circuit includes an external power supply, a charging management chip, a first main charging position, and a second main charging position. The external power supply is connected to two signal output ports of the charging management chip through external adjustment tubes VT1 and VT2, respectively. The two sampling signal input ports of the charging management chip are connected to the first main charging position and the second main charging position, respectively.

[0006] The No. 1 main charging position is connected to the No. 1 sampling circuit and the No. 1 discharging circuit, the No. 2 main charging position is connected to the No. 2 sampling circuit and the No. 2 discharging circuit, the No. 1 sampling circuit, the No. 1 discharging circuit, the No. 2 sampling circuit and the No. 2 discharging circuit are all connected to a main control microcontroller, the No. 1 sampling circuit and the No. 2 sampling circuit collect the voltage across the No. 1 main charging position and the No. 2 main charging position and transmit it to the main control microcontroller, and the main control microcontroller controls the No. 1 discharging circuit and the No. 2 discharging circuit to discharge the No. 1 main charging position and the No. 2 main charging position.

[0007] The present invention is further configured as follows: the charging management chip is a DS2711 chip, the external power supply is connected to the emitter of the external adjustment tube VT1, the base of the external adjustment tube VT1 is connected to the CC1 interface of the charging management chip, and the collector of the external adjustment tube VT1 is connected to the positive electrode of the first main charging position;

[0008] The external power supply is connected to the emitter of the external adjustment tube VT2, the base of the external adjustment tube VT2 is connected to the CC2 interface of the charging management chip, and the collector of the external adjustment tube VT2 is connected to the positive electrode of the second main charging position.

[0009] The present invention is further configured as follows: the main control microcontroller is an STC15W401AS microcontroller, the first sampling circuit includes R17 and RP1 connected in series, and the middle pin of RP1 is connected to the P1.0 interface of the charging management chip;

[0010] The second sampling circuit includes R21 and RP2 connected in series, and the middle pin of RP2 is connected to the P1.1 interface of the charging management chip.

[0011] The present invention is further configured as follows: the first discharge circuit includes R16 and VT3, the R16 is connected to the collector of the external adjustment tube VT1, the collector of the VT3 is connected to R16, and the base of the VT3 is connected to the P3.6 interface of the main control microcontroller;

[0012] The second discharge circuit includes R20 and VT4, wherein R20 is connected to the collector of the external adjustment tube VT2, the collector of VT4 is connected to R20, and the base of VT4 is connected to the P3.7 interface of the main control microcontroller.

[0013] The present invention is further configured as follows: the main control microcontroller is connected to an optocoupler IC3 and an optocoupler IC4, the light emitting diode of the optocoupler IC3 is connected to the P3.0 interface of the main control microcontroller, the phototransistor of the optocoupler IC3 is connected to the emitter of the external adjustment tube VT1, and the collector of the external adjustment tube VT1 is connected to the positive electrode of the first main charging position;

[0014] The light emitting diode of the optocoupler IC4 is connected to the P3.3 interface of the main control microcontroller, the photosensitive transistor of the optocoupler IC4 is connected to the emitter of the external adjustment tube VT2, and the collector of the external adjustment tube VT2 is connected to the positive electrode of the second main charging position.

[0015] The present invention is further configured as follows: the No. 1 main charging position is connected to a first indicator light, the first indicator light is connected to the LED1 port of the charging management chip, the No. 2 main charging position is connected to a second indicator light, and the second indicator light is connected to the LED2 interface of the charging management chip.

[0016] The present invention is further configured as follows: the external power supply is a type-c power interface with an input voltage of 5V.

[0017] The present invention is further configured as follows: the charging management chip, the main control microcontroller, the No. 1 sampling circuit, the No. 1 discharge circuit, the No. 2 sampling circuit and the No. 2 discharge circuit are all connected to a circuit board, and the circuit board is installed in the charging box.

[0018] The present invention is further configured as follows: the No. 1 main charging position and the No. 2 main charging position are both arranged on the charging box, and the interface of the external power supply is opened on the side wall of the charging box.

[0019] The present invention is further configured as follows: a protective cover is buckled on the charging box.

[0020] When charging the button battery, place the button battery in the No. 1 main charging position and the No. 2 main charging position on the charging box, and plug the USB power supply with the Type-C interface into the interface of the external power supply. The No. 1 sampling circuit and the No. 2 sampling circuit sample the voltage of the No. 1 main charging position and the No. 2 main charging position and transmit the sample to the charging main control microcontroller through the P1.0 and P1.1 interfaces. When the main control microcontroller detects that the voltage of the No. 1 main charging position / No. 2 main charging position is lower than 0.9V, the charging management chip is normally connected and controls the working state of the external adjustment tube VT1 / external adjustment tube VT2, thereby adjusting the size of the charging current to charge the main charging battery I and main charging battery II; when the main control microcontroller detects that the voltage of the No. 1 main charging position / No. 2 main charging position is higher than 0.9V and less than 1.3V, the light-emitting diode of the optocoupler IC3 / optocoupler IC4 lights up, the phototransistor is turned on, the external adjustment tube VT1 / external adjustment tube VT2 is disconnected from the charging management chip, and the first discharge circuit / second discharge circuit discharges the No. 1 main charging position / No. 2 main charging position, which can effectively avoid the battery memory effect caused by overcharging and extend the battery life.

[0021] In summary, the present invention has the following beneficial effects:

[0022] 1. Through the settings of discharge circuit No. 1, discharge circuit No. 2, and external adjustment tubes VT1 and VT2, adjustments are made when the battery is overcharged or low on power, reducing memory effect damage;

[0023] 2. Through the optocoupler IC3 and optocoupler IC4 connected to the external adjustment tube VT1 and the external adjustment tube VT2, the charging state is cut off when overcharging occurs and the discharge state is maintained;

[0024] 3. The first indicator light and the second indicator light connected to the first main charging position and the second main charging position can indicate the charging status of the first main charging position and the second main charging position. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a circuit diagram of the present invention;

[0026] Figure 2 It is a schematic diagram of the overall structure of the present invention;

[0027] Figure 3 This is a schematic diagram of the structure inside the charging box used in the present invention.

[0028] In the figure, 1. External power supply; 2. Charging management chip; 21. External adjustment tube VT1; 22. External adjustment tube VT2; 3. Main charging position No. 1; 31. Sampling circuit No. 1; 32. Discharging circuit No. 1; 33. Optocoupler IC3; 34. First indicator light; 4. Main charging position No. 2; 41. Sampling circuit No. 2; 42. Discharging circuit No. 2; 43. Optocoupler IC4; 44. Second indicator light; 5. Main control microcontroller; 6. Charging box; 61. Circuit board; 62. Protective cover. DETAILED DESCRIPTION

[0029] The present invention is further described below in conjunction with the accompanying drawings. Those skilled in the art will readily appreciate the other advantages and benefits of the present invention from the disclosure herein. Terms such as "upper," "lower," "left," "right," and "center" are used herein for clarity and are not intended to limit the scope of the present invention. Any changes or adjustments to these terms, without materially altering the technical content, are considered within the scope of the present invention.

[0030] Example:

[0031] like Figure 1 As shown, a nickel-metal hydride button battery offline charging circuit for hearing aids designed by the present invention includes an external power supply 1, a charging management chip 2, a first main charging position 3, and a second main charging position 4. The external power supply 1 is a Type-C power interface with an input voltage of 5V. The charging management chip 2 is a DS2711 chip. The external power supply 1 is connected to the CC1 and CC2 interfaces of the charging management chip 2 respectively. An external adjustment tube VT1 21 is connected between the No. 1 interface of the external power supply 1 and the CC1 interface of the charging management chip 2. The No. 1 interface of the external power supply 1 is connected to the emitter of the external adjustment tube VT1 21, the base of the external adjustment tube VT1 21 is connected to the CC1 interface of the charging management chip 2, the collector of the external adjustment tube VT1 21 is connected to the positive electrode of the No. 1 main charging position 3, and the No. 1 main charging position 3 is connected to the VP1 interface of the external power supply 1.

[0032] An external adjustment tube VT2 22 is connected between external power supply 1 and the CC2 interface of charge management chip 2. Interface 1 of external power supply 1 is connected to the emitter of external adjustment tube VT2 22, the base of external adjustment tube VT2 22 is connected to the CC2 interface of charge management chip 2, and the collector of external adjustment tube VT2 22 is connected to the positive electrode of main charging station 4, which is connected to the VP2 interface of external power supply 1. The VP1 and VP2 interfaces of charge management chip 2 detect the voltages of main charging stations 1 and 2. When VP1 and VP2 interfaces detect that the battery voltages in main charging stations 1 and 2 are too low, CC1 and CC2 interfaces reduce the charging current of external adjustment tubes VT1 21 and VT2 22, pre-charging main charging stations 3 and 4.

[0033] like Figure 1 As shown, the first main charging station 3 is connected to the first sampling circuit 31 and the first discharge circuit 32, and the second main charging station 4 is connected to the second sampling circuit 41 and the second discharge circuit 42. The first sampling circuit 31, the first discharge circuit 32, the second sampling circuit 41, and the second discharge circuit 42 are all connected to the main control microcontroller 5. The first sampling circuit 31 and the second sampling circuit 41 collect the voltage across the first main charging station 3 and the second main charging station 4 and transmit it to the main control microcontroller 5. The main control microcontroller 5 is an STC15W401AS microcontroller. The first sampling circuit 31 includes R17 and RP1 connected in series. The middle pin of RP1 is connected to the P1.0 interface of the charge management chip 2.

[0034] like Figure 1 As shown, discharge circuit 32 No. 1 includes R16 and VT3. R16 is connected to the collector of external adjustment tube VT121. The collector of VT3 is connected to R16. The base of VT3 is connected to the P3.6 interface of the master microcontroller 5. The master microcontroller 5 is connected to an optocoupler IC333. The light-emitting diode of optocoupler IC333 is connected to the P3.0 interface of the master microcontroller 5. The phototransistor of optocoupler IC333 is connected to the emitter of external adjustment tube VT121. The collector of external adjustment tube VT121 is connected to the positive electrode of the first main charging position 3.

[0035] The first sampling circuit 31 samples the voltage across the first main charging bit 3 and transmits it to the main control microcontroller 5 through the P1.0 pin. When the main control microcontroller 5 detects that the voltage of the first main charging bit 3 is greater than 0.9V and less than 1.3V, it issues two instructions at the same time:

[0036] Instruction 1: The P3.6 interface outputs a high level to make VT3 forward-biased. The battery in the No. 1 main charging position 3 is connected through the positive electrode → R16 → VT3 collector → VT3 emitter to ground → through the ground back to the No. 1 main charging position 3 negative electrode, forming a discharge circuit;

[0037] Instruction 2: The P3.0 interface outputs a low level, the light-emitting diode of the optocoupler IC3 33 is forward-biased and turns on, the phototransistor is turned on by the light, VT1 is reverse-biased and cut off, and the connection with the CC1 interface of the charge management chip 2 is disconnected to maintain the discharge state of the battery in the No. 1 main charging position 3.

[0038] When the main control microcontroller 5 detects that the voltage of the No. 1 main charging bit 3 is less than 0.9V, it issues two instructions at the same time:

[0039] Instruction three: P3.6 port outputs a low level to make VT3 reverse biased and cut off, cutting off the discharge path and stopping the battery from discharging;

[0040] Instruction 4: P3.0 port outputs a high level, the light-emitting diode of the optocoupler IC3 33 is reverse biased and cut off, stops emitting light, the phototransistor is cut off due to lack of light, VT1 is disconnected from the control of P3.0 port, the base is connected to the CC1 interface of the charging management chip 2, and returns to the normal charging state of the No. 1 main charging position 3.

[0041] like Figure 1 As shown, sampling circuit No. 2 41 includes R21 and RP2 connected in series, with the middle pin of RP2 connected to the P1.1 interface of charge management chip 2. Discharge circuit No. 2 42 includes R20 and VT4. R20 is connected to the collector of external adjustment tube VT2 22, the collector of VT4 is connected to R20, and the base of VT4 is connected to the P3.7 interface of main control microcontroller 5. Main control microcontroller 5 is connected to optocoupler IC4 43, the light-emitting diode of optocoupler IC4 43 is connected to the P3.3 interface of main control microcontroller 5, the phototransistor of optocoupler IC4 43 is connected to the emitter of external adjustment tube VT2 22, and the collector of external adjustment tube VT2 22 is connected to the positive terminal of main charge terminal No. 2 4.

[0042] The second sampling circuit 41 samples the voltage across the second main charging bit 4 and transmits it to the main control microcontroller 5 through the P1.1 pin. When the main control microcontroller 5 detects that the voltage of the second main charging bit 4 is greater than 0.9V and less than 1.3V, it issues two instructions at the same time:

[0043] Instruction 1: The P3.7 interface outputs a high level to make VT4 forward-biased. The battery in the No. 2 main charging position 4 is connected through the positive electrode → R20 → VT4 collector → VT4 emitter to ground → through the ground back to the negative electrode of the No. 2 main charging position 4, forming a discharge circuit;

[0044] Instruction 2: The P3.3 interface outputs a low level, the light-emitting diode of the optocoupler IC4 43 is forward-biased and turns on to emit light, the phototransistor is turned on by the light, VT2 is reverse-biased and cut off, and the connection with the CC2 interface of the charge management chip 2 is disconnected to maintain the discharge state of the battery in the second main charging position 4.

[0045] When the main control microcontroller 5 detects that the voltage of the second main charging bit 4 is less than 0.9V, it issues two instructions at the same time:

[0046] Instruction three: P3.7 port outputs a low level to make VT4 reverse biased and cut off, cutting off the discharge path and stopping the battery from discharging;

[0047] Instruction 4: P3.3 port outputs a high level, the light-emitting diode of the optocoupler IC4 43 is reverse biased and cut off, stops emitting light, the phototransistor is cut off due to lack of light, VT2 is disconnected from the control of P3.3 port, the base is connected to the CC1 interface of the charging management chip 2, and returns to the normal charging state of the No. 1 main charging position 3.

[0048] like Figures 1 to 3 As shown, the first main charging station 3 is connected to a first indicator light 34, which is connected to the LED1 port of the charge management chip 2. The second main charging station 4 is connected to a second indicator light 44, which is connected to the LED2 port of the charge management chip 2. The charge management chip 2, the main control microcontroller 5, the first sampling circuit 31, the first discharge circuit 32, the second sampling circuit 41, and the second discharge circuit 42 are all connected to a circuit board 61, which is installed in the charging box 6. The first and second main charging stations 3 and 4 are both located on the charging box 6. The interface for the external power supply 1 is opened on the side wall of the charging box 6, and the charging box 6 is fastened with a protective cover 62.

[0049] The implementation principle of the above embodiment is: when charging the button battery, place the button battery in the No. 1 main charging position 3 and the No. 2 main charging position 4 on the charging box 6, and plug the USB power supply with the type-c interface into the interface of the external power supply 1. The No. 1 sampling circuit 31 and the No. 2 sampling circuit 41 sample the voltages of the No. 1 main charging position 3 and the No. 2 main charging position 4 and transmit them to the charging main control microcontroller 5 through the P1.0 and P1.1 interfaces. When the main control microcontroller 5 detects that the voltage of the No. 1 main charging position 3 / the No. 2 main charging position 4 is lower than 0.9V, the charging management chip 2 is normally connected and controls the working state of the external adjustment tube VT1 21 / the external adjustment tube VT2 22, thereby adjusting the size of the charging current to charge the batteries in the No. 1 main charging position 3 and the No. 2 main charging position 4; when the main control microcontroller 5 detects that the voltage of the No. 1 main charging position 3 / the No. 2 main charging position 4 is higher than 0.9V and less than 1.3V, the light-emitting diode of the optocoupler IC333 / the optocoupler IC4 43 emits light, the phototransistor is turned on, and the external adjustment tube VT1 21 / The external adjustment tube VT222 is disconnected from the charge management chip 2, and the first discharge circuit / the second discharge circuit discharges the first main charging position 3 / the second main charging position 4, which can effectively avoid the battery memory effect caused by overcharging and extend the battery life.

[0050] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as such modifications are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A nickel-metal hydride button battery offline charging circuit for hearing aids, characterized by: The invention comprises an external power supply (1), a charging management chip (2), a first main charging position (3) and a second main charging position (4); the external power supply (1) is connected to two signal output ports of the charging management chip (2) via an external adjustment tube VT1 (21) and an external adjustment tube VT2 (22), respectively; and the two sampling signal input ports of the charging management chip (2) are connected to the first main charging position (3) and the second main charging position (4) respectively; The first main charging position (3) is connected to a first sampling circuit (31) and a first discharge circuit, the second main charging position (4) is connected to a second sampling circuit (41) and a second discharge circuit, the first sampling circuit (31), the first discharge circuit, the second sampling circuit (41) and the second discharge circuit (42) are all connected to a main control single chip computer (5), the first sampling circuit (31) and the second sampling circuit (41) collect voltages at both ends of the first main charging position (3) and the second main charging position (4) and transmit them to the main control single chip computer (5), and the main control single chip computer (5) controls the first discharge circuit and the second discharge circuit to discharge the first main charging position (3) and the second main charging position (4); The charging management chip (2) is a DS2711 chip, the external power supply (1) is connected to the emitter of the external adjustment tube VT1 (21), the base of the external adjustment tube VT1 (21) is connected to the CC1 interface of the charging management chip (2), and the collector of the external adjustment tube VT1 (21) is connected to the positive electrode of the first main charging position (3); The external power supply (1) is connected to the emitter of the external adjustment tube VT2 (22), the base of the external adjustment tube VT2 (22) is connected to the CC2 interface of the charging management chip (2), and the collector of the external adjustment tube VT2 (22) is connected to the positive electrode of the second main charging position (4); The main control single chip microcomputer (5) is a STC15W401AS single chip microcomputer, the first sampling circuit (31) comprises R17 and RP1 connected in series, and the middle pin of RP1 is connected to the P1.0 interface of the charging management chip (2); The second sampling circuit (41) comprises R21 and RP2 connected in series, wherein the middle pin of RP2 is connected to the P1.1 interface of the charging management chip (2); The first discharge circuit (32) includes R16 and VT3, wherein R16 is connected to the collector of the external adjustment tube VT1 (21), the collector of VT3 is connected to R16, and the base of VT3 is connected to the P3.6 interface of the main control microcontroller (5); the second discharge circuit (42) includes R20 and VT4, wherein R20 is connected to the collector of the external adjustment tube VT2 (22), the collector of VT4 is connected to R20, and the base of VT4 is connected to the P3.7 interface of the main control microcontroller (5); The main control single chip computer (5) is connected to an optocoupler IC3 (33) and an optocoupler IC4 (43), the light emitting diode of the optocoupler IC3 (33) is connected to the P3.0 interface of the main control single chip computer (5), the photosensitive transistor of the optocoupler IC3 (33) is connected to the emitter of the external adjustment tube VT1 (21), and the collector of the external adjustment tube VT1 (21) is connected to the positive electrode of the first main charging position (3); The light emitting diode of the optical coupler IC4 (43) is connected to the P3.3 interface of the main control microcontroller (5), the photosensitive transistor of the optical coupler IC4 (43) is connected to the emitter of the external adjustment tube VT2 (22), and the collector of the external adjustment tube VT2 (22) is connected to the positive electrode of the second main charging position (4); The No. 1 sampling circuit (31) samples the voltage across the No. 1 main charging position (3) and transmits it to the main control microcontroller 5 through the P1.0 pin. When the main control microcontroller 5 detects that the voltage of the No. 1 main charging position (3) is greater than 0.9V and less than 1.3V, it simultaneously issues two instructions: Instruction 1: The P3.6 interface outputs a high level to turn on VT3 in the forward bias, and the battery in the No. 1 main charging position (3) is connected via the positive electrode → R16 → VT3 collector → VT3 emitter to the ground → through the ground back to the negative electrode of the No. 1 main charging position (3), forming a discharge circuit; Instruction 2: The P3.0 interface outputs a low level, the light-emitting diode of the optocoupler IC3 (33) is forward-biased and turns on to emit light, the phototransistor is turned on by the light, VT1 is reverse-biased and turns off, and the connection with the CC1 interface of the charge management chip 2 is disconnected to maintain the discharge state of the battery in the first main charging position (3); When the main control microcontroller 5 detects that the voltage of the No. 1 main charging position (3) is less than 0.9V, it issues two instructions at the same time: Instruction three: P3.6 port outputs a low level to make VT3 reverse biased and cut off, cutting off the discharge path and stopping the battery from discharging; Instruction 4: The P3.0 port outputs a high level, the light-emitting diode of the optocoupler IC3 (33) is reverse-biased and cut off, stops emitting light, the phototransistor is cut off due to the lack of light, VT1 is disconnected from the control of the P3.0 port, the base is connected to the CC1 interface of the charging management chip 2, and returns to the normal charging state of the No. 1 main charging position (3).

2. The offline charging circuit for nickel-metal hydride button batteries for hearing aids according to claim 1, characterized in that: The first main charging position (3) is connected to a first indicator light (34), which is connected to an LED1 port of a charging management chip (2); the second main charging position (4) is connected to a second indicator light (44), which is connected to an LED2 port of a charging management chip (2).

3. The offline charging circuit for nickel-metal hydride button batteries for hearing aids according to claim 1, characterized in that: The external power supply (1) is a type-c power interface with an input voltage of 5V.

4. The offline charging circuit for nickel-metal hydride button batteries for hearing aids according to claim 3, characterized in that: The charging management chip (2), the main control single chip computer (5), the first sampling circuit (31), the first discharge circuit, the second sampling circuit (41) and the second discharge circuit are all connected to a circuit board (61), and the circuit board (61) is installed in the charging box (6).

5. The offline charging circuit for nickel-metal hydride button batteries for hearing aids according to claim 1, characterized in that: The first main charging position (3) and the second main charging position (4) are both arranged on the charging box (6), and the interface of the external power supply (1) is opened on the side wall of the charging box (6).

6. The offline charging circuit for nickel-metal hydride button batteries for hearing aids according to claim 5, characterized in that: A protective cover (62) is buckled onto the charging box (6).

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