CN210246363U

CN210246363U - Small-electric-quantity charging equipment

Info

Publication number: CN210246363U
Application number: CN201921296973.9U
Authority: CN
Inventors: Chao Zhao; 赵超
Original assignee: Queclink Wireless Solutions Co Ltd
Current assignee: Queclink Wireless Solutions Co Ltd
Priority date: 2019-08-09
Filing date: 2019-08-09
Publication date: 2020-04-03
Anticipated expiration: 2029-08-09

Abstract

The utility model provides a little electric quantity battery charging outfit, little electric quantity battery charging outfit includes: the circuit comprises a connector, a micro control unit, three MOS tubes, a 100K omega-level resistor, an omega-level resistor, three pull-up resistors and three triodes used for switching. The utility model discloses an equipment can be safely, high-efficiently with 5V direct current for miniature rechargeable battery charging, the utility model is suitable for an under the little condition of battery power, the electric current of resistance and MOS pipe can be controlled in reliable within range. The utility model utilizes the difference of the parasitic diode and the current after conduction when the MOS tube is conducted and closed, and combines the resistance current limiting to control the charging current; the ADC value is read through the micro control unit, and the charging control is realized by controlling the opening and closing of the three groups of MOS tubes through the GPIO.

Description

Small-electric-quantity charging equipment

Technical Field

The utility model relates to a battery charging outfit technical field, concretely relates to little electric quantity battery charging outfit.

Background

The rechargeable battery which can be used repeatedly has long service time and low cost for long-term use, and has more advantages than the common battery from the viewpoint of environmental protection and energy saving, so the rechargeable battery is widely applied. The principle of charging the rechargeable battery is to pass direct current in the opposite direction of discharge to recover the active material in the battery. The charging of batteries in various electronic devices generally impairs the health and life of the batteries, and there is a lack of a safe and efficient device for charging small rechargeable batteries with 5V dc current.

Disclosure of Invention

An object of the utility model is to provide a little electric quantity battery charging outfit to solve current problem.

In order to achieve the above object, the present invention provides a small electric quantity charging device, which includes a connector, a micro control unit, a first MOS transistor, a third MOS transistor, a first resistor, a third resistor, and a fifth resistor; the connector is connected with direct current and is connected to the D pole of the third MOS tube; the micro control unit comprises at least one ADC and at least two GPIOs, the ADC is connected with the positive pole of the rechargeable battery, the GPIO1 is connected with the G pole of the first MOS tube, and the GPIO3 is connected with the G pole of the third MOS tube; the third MOS tube is internally provided with a parasitic diode, and S poles of the first MOS tube and the third MOS tube are connected together; one end of the first resistor is connected with the D pole of the first MOS tube, and the other end of the first resistor is connected with the + pole of the rechargeable battery; the third resistor is connected between the S pole and the G pole of the first MOS tube; and the fifth resistor is connected between the S pole and the G pole of the third MOS tube.

Further, little electric quantity charging equipment still includes second MOS pipe, second resistance and fourth resistance, little the control unit contains an ADC and three GPIO, and GPIO2 connects the G utmost point of second MOS pipe, and the S utmost point of first MOS pipe, second MOS pipe and third MOS pipe links together, the resistance value of second resistance is less than first resistance, the one end of second resistance is connected with the D utmost point of second MOS pipe, the other end of second resistance is connected to rechargeable battery' S + utmost point with first resistance jointly, fourth resistance is connected between the S utmost point and the G utmost point of second MOS pipe.

Further, the small-power charging device further comprises a first switch, a second switch and a third switch, wherein the first switch is connected between the GPIO1 and the D pole of the first MOS transistor, the second switch is connected between the GPIO2 and the D pole of the second MOS transistor, and the third switch is connected between the GPIO3 and the D pole of the third MOS transistor.

Further, the first switch, the second switch and the third switch are triodes.

Furthermore, the first MOS tube, the second MOS tube and the third MOS tube are P-MOS tubes.

Further, the third resistor, the fourth resistor and the fifth resistor are pull-up resistors.

Furthermore, the resistance value of the first resistor is 100-1000K omega, and the resistance value of the second resistor is 1-10 omega.

Further, the connector is connected with 5V direct current.

To sum up, owing to adopted above-mentioned technical scheme, compared with the prior art, the utility model, possess following beneficial effect:

the utility model discloses an equipment can be safely, high-efficiently with 5V direct current for miniature rechargeable battery charging, the utility model is suitable for an under the little condition of battery power, the electric current of resistance and MOS pipe can be controlled in reliable within range. The utility model utilizes the difference of the parasitic diode and the current after conduction when the MOS tube is conducted and closed, and combines the resistance current limiting to control the charging current; the ADC value is read through the micro control unit, and the charging control is realized by controlling the opening and closing of the MOS tube through the GPIO. When the voltage is lower, the battery is charged by adopting a smaller current, so that the damage to the battery caused by overlarge current is avoided, and the service life of the battery is prolonged.

Drawings

Fig. 1 is a schematic structural diagram of a small-power charging device according to a first embodiment;

fig. 2 is a schematic flow chart of a small-power charging device according to the first embodiment.

Fig. 3 is a schematic structural diagram of a small-power charging device according to a second embodiment.

The reference numerals are explained below:

1. the device comprises a connector, 2, a micro control unit, 3, a first resistor, 4, a second resistor, 5, a third resistor, 6, a fourth resistor, 7, a fifth resistor, 8, a first MOS (metal oxide semiconductor) transistor, 9, a second MOS transistor, 10, a third MOS transistor, 11, a first switch, 12, a second switch, 13, a third switch, 14 and a rechargeable battery.

Detailed Description

The technical solution proposed by the present invention will be described in more detail with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description. It should be noted that the drawings are in simplified form and are not to precise scale, and are provided for convenience and clarity in order to facilitate the description of the embodiments of the present invention.

In the description of the present invention, it is to be understood that the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are merely for convenience of description and to simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention. In the description of the present invention, unless otherwise specified, "a plurality" means two or more, and "at least two" means also two or more.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted", "connected" and "contacting" are to be interpreted broadly, e.g. as either a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

When embodiments of the present invention refer to the ordinal numbers "first", "second", etc., it should be understood that the terms are used for distinguishing only when they do express the ordinal order in context.

Example one

Referring to fig. 1, a small-power charging device includes: the circuit comprises a connector 1, a micro control unit 2, a first resistor 3, a second resistor 4, a third resistor 5, a fourth resistor 6, a fifth resistor 7, a first MOS (metal oxide semiconductor) transistor 8, a second MOS transistor 9, a third MOS transistor 10, a first switch 11, a second switch 12 and a third switch 13.

The connector 1 has 2 interfaces, wherein 1pin is connected with the + pole of 5V, and 3 pins are connected with the ground. The 1pin of the connector 1 is connected to the D pole of the third MOS transistor 10.

The micro control unit 2 comprises an ADC and three GPIOs, wherein the ADC is connected with the + pole of the rechargeable battery 14, the GPIO1 is connected with the base of the first switch 11, the GPIO2 is connected with the base of the second switch 12, and the GPIO3 is connected with the base of the third switch 13.

One end of the first resistor 3 is connected with the D pole of the first MOS transistor 8, and the other end of the first resistor 3 and the second resistor 4 are connected to the + pole of the rechargeable battery 14 in common.

One end of the second resistor 4 is connected with the D pole of the second MOS transistor 8, and the other end of the second resistor 4 and the first resistor 3 are connected to the + pole of the rechargeable battery 14.

The third resistor 5, the fourth resistor 6 and the fifth resistor 7 are pull-up resistors. The third resistor 5 is connected between the S pole and the G pole of the first MOS tube 8, the fourth resistor 6 is connected between the S pole and the G pole of the second MOS tube 9, and the fifth resistor 7 is connected between the S pole and the G pole of the third MOS tube 10.

The first MOS transistor 8, the second MOS transistor 9 and the third MOS transistor 10 are P-MOS transistors and are provided with a D pole, an S pole and a G pole. The S poles of the first MOS tube 8, the second MOS tube 9 and the third MOS tube 10 are connected together. The G pole of the first MOS transistor 8 is connected to the collector of the first switch 11, the G pole of the second MOS transistor 9 is connected to the collector of the second switch 12, the third MOS transistor 10 has a parasitic diode therein, and the G pole of the third MOS transistor 10 is connected to the collector of the third switch 13.

The first switch 11, the second switch 12 and the third switch 13 are transistors for switching, and fig. 1 shows NPN transistors. The emitters of the first switch 11, the second switch 12 and the third switch 13 are grounded.

When the GPIOs 1 and 2 output high levels, the first MOS transistor 8 and the second MOS transistor 9 are turned on; when the GPIOs 1 and 2 output a low level, the first MOS transistor 8 and the second MOS transistor 9 are turned off. The third MOS transistor 10 cannot be turned off when the GPIO3 outputs a low level because of the parasitic diode therein, and when the GPIO3 outputs a high level, the impedance between the D-pole and the S-pole of the third MOS transistor 10 decreases, and the current passing through the third MOS transistor becomes large.

Please refer to fig. 2

The mcu 2 reads the voltage of the rechargeable battery 14 through the ADC pin, because the rechargeable battery 14 has internal resistance and cannot be read during charging, otherwise the voltage will float high, so the method of reading the battery voltage is: every 10s, the GPIO1 outputs low level, the GPIO2 outputs high level, and the time lasts for 1 s; in this 1s, the mcu 2 reads the voltage three times through the ADC, and the battery voltage is the average of the three times. The micro control unit 2 selects the following suitable phases depending on the voltage value of the rechargeable battery 14:

(1) initial stage

The micro control unit 2 controls the GPIO1 to output low level and closes the first MOS transistor 8; the GPIO2 outputs low level, and the second MOS tube 9 is closed; the GPIO3 outputs a high level when the charging of the rechargeable battery 14 is turned off.

(2) Very small current charging stage (battery voltage < 2V time)

At this time, the GPIO1 outputs a high level, and the first MOS transistor 8 is turned on; the GPIO2 outputs low level, and the second MOS tube 9 is closed; the GPIO3 outputs a high level to turn on the third MOS transistor 10.

The charging current at this time is (5V-VBAT)/R1; where VBAT is the battery voltage, and R1 is the resistance of the first resistor 3. The first resistor 3 is ensured to be in the 100K omega level, so that the charging current can be kept in the muA level, and the charging is carried out at the extremely low current, so that the battery is ensured not to be damaged at the extremely low voltage.

(3) Charging stage with small current (2V is less than or equal to battery voltage and less than 3.5V)

At this time, the GPIO1 outputs a low level to turn off the first MOS transistor 8; the GPIO2 outputs high level and turns on the second MOS tube 9; GPIO3 outputs a low level to reduce the current through the third MOS transistor 10, which will pass through the parasitic diode, but the current will be smaller.

The charging current at this time is (5V-VDQ 3-VBAT)/R2; VBAT is the battery voltage, VDQ3 is the voltage across the parasitic diode of the third MOS transistor 10, and R2 is the resistance of the second resistor 4. Along with the battery voltage becomes higher, the current can be smaller and smaller, the second resistor 4 is guaranteed to be in the ohm level, the charging current can be kept in the mA level, and the low current charging stage is guaranteed to be used for charging when the battery voltage is small.

(4) A large current charging stage (when the battery voltage is less than or equal to 3.5V and less than 4.2V)

At this time, the GPIO1 outputs a low level to turn off the first MOS transistor 8; the GPIO2 outputs high level and turns on the second MOS tube 9; the GPIO3 outputs a high level to turn on the third MOS transistor 10.

The charging current at this time is (5V-VBAT)/R2; where VBAT is the battery voltage, and R2 is the resistance of the second resistor 4. The second resistor 4 is ensured to be in an ohm level, so that the charging current can be kept in a mA level; the charging state is normal, the current is obviously larger than the charging stage with small current, and the current is smaller and smaller as the voltage of the battery becomes higher.

(5) End of charge (when the battery voltage is more than or equal to 4.2V)

The GPIO1 outputs low level to close the first MOS transistor 8; the GPIO2 outputs low level, and the second MOS tube 9 is closed; the GPIO3 outputs high level; at this time, the battery charging is closed, and the charging process is ended.

The small-electric-quantity charging equipment of the embodiment utilizes the MOS tube to be switched on and off, controls the charging current by combining the parasitic diode and the difference of the current after the conduction and the resistance current limiting, and can safely and efficiently charge the small rechargeable battery with the 5V direct current. When the voltage of the battery is less than 2V, the battery is charged by using the micro current of the mu A level, so that the damage to the battery caused by overlarge current is avoided. When the voltage of the battery is more than or equal to 2V and less than 3.5V, the battery is charged by using the low current of mA level, the current is obviously improved in the charging stage of the relatively low current, but the battery is not damaged due to overlarge current. When the battery voltage is less than 4.2V and less than 3.5V, the current is further increased in a small current charging stage, and the charging speed is accelerated. The small-electric-quantity charging equipment of the embodiment charges by adopting currents of different sizes in stages, and when the voltage is lower, the small currents are adopted for charging, so that the damage to the battery caused by overlarge currents is avoided, and the service life of the battery is prolonged.

Example two

Referring to fig. 3, a small-power charging device includes: the circuit comprises a connector 1, a micro control unit 2, a first resistor 3, a third resistor 5, a fifth resistor 7, a first MOS (metal oxide semiconductor) transistor 8, a third MOS transistor 10, a first switch 11 and a third switch 13.

The micro control unit 2 comprises an ADC and two GPIOs, wherein the ADC is connected with the + pole of the rechargeable battery 14, the GPIO1 is connected with the base of the first switch 11, and the GPIO3 is connected with the base of the third switch 13.

One end of the first resistor 3 is connected to the D pole of the first MOS transistor 8, and the other end of the first resistor 3 is connected to the + pole of the rechargeable battery 14.

The third resistor 5 and the fifth resistor 7 are pull-up resistors. The third resistor 5 is connected between the S pole and the G pole of the first MOS tube 8, and the fifth resistor 7 is connected between the S pole and the G pole of the third MOS tube 10.

The first MOS transistor 8 and the third MOS transistor 10 are P-MOS transistors and have a D pole, an S pole and a G pole. The S poles of the first MOS tube 8 and the third MOS tube 10 are connected together. The G pole of the first MOS transistor 8 is connected to the collector of the first switch 11, the third MOS transistor 10 has a parasitic diode therein, and the G pole of the third MOS transistor 10 is connected to the collector of the third switch 13.

The first switch 11 and the third switch 13 are transistors that function as switches, and the emitters of the first switch 11 and the third switch 13 are grounded.

The micro control unit 2 selects the following suitable phases depending on the voltage value of the rechargeable battery 14:

(1) initial stage

The micro control unit 2 controls the GPIO1 to output low level and closes the first MOS transistor 8; the GPIO3 outputs a high level when the charging of the rechargeable battery 14 is turned off.

(2) Very low current charging phase

At this time, the GPIO1 outputs a high level, and the first MOS transistor 8 is turned on; the GPIO3 outputs a high level to turn on the third MOS transistor 10.

(3) High current charging stage

At this time, the GPIO1 outputs a low level to turn off the first MOS transistor 8; the GPIO3 outputs a high level to turn on the third MOS transistor 10.

(4) End of charge

The GPIO1 outputs low level to close the first MOS transistor 8; the GPIO3 outputs high level; at this time, the battery charging is closed, and the charging process is ended.

The small-electric-quantity charging equipment of the embodiment utilizes the MOS tube to be switched on and off, controls the charging current by combining the parasitic diode and the difference of the current after the conduction and the resistance current limiting, and can safely and efficiently charge the small rechargeable battery. The small-electric-quantity charging equipment of the embodiment charges by adopting currents of different sizes in stages, and when the voltage is lower, the small currents are adopted for charging, so that the damage to the battery caused by overlarge currents is avoided, and the service life of the battery is prolonged.

The above description is only for the preferred embodiment of the present invention, and does not limit the present invention. Any technical personnel who belongs to the technical field, in the scope that does not deviate from the technical scheme of the utility model, to the technical scheme and the technical content that the utility model discloses expose do the change such as the equivalent replacement of any form or modification, all belong to the content that does not break away from the technical scheme of the utility model, still belong to within the scope of protection of the utility model.

Claims

1. A small-charge charging apparatus, comprising:

the connector is connected with direct current and connected to the D pole of the third MOS tube;

the micro-control unit comprises at least one ADC and at least two GPIOs, the ADC is connected with the positive pole of the rechargeable battery, the GPIO1 is connected with the G pole of the first MOS tube, and the GPIO3 is connected with the G pole of the third MOS tube;

a first MOS transistor;

the third MOS tube is internally provided with a parasitic diode, and S poles of the first MOS tube and the third MOS tube are connected together;

one end of the first resistor is connected with the D pole of the first MOS tube, and the other end of the first resistor is connected to the + pole of the rechargeable battery;

the third resistor is connected between the S pole and the G pole of the first MOS tube;

and the fifth resistor is connected between the S pole and the G pole of the third MOS tube.

2. The small-power charging device according to claim 1, further comprising a second MOS transistor, a second resistor and a fourth resistor, wherein the micro control unit comprises an ADC and three GPIOs, the GPIO2 is connected to the G pole of the second MOS transistor, the S poles of the first MOS transistor, the second MOS transistor and the third MOS transistor are connected together, the resistance value of the second resistor is smaller than that of the first resistor, one end of the second resistor is connected to the D pole of the second MOS transistor, the other end of the second resistor and the first resistor are connected to the + pole of the rechargeable battery, and the fourth resistor is connected between the S pole and the G pole of the second MOS transistor.

3. The small-charge charging device according to claim 2, further comprising a first switch connected between GPIO1 and the G-pole of the first MOS transistor, a second switch connected between GPIO2 and the G-pole of the second MOS transistor, and a third switch connected between GPIO3 and the G-pole of the third MOS transistor.

4. The small-charge charging device according to claim 3, wherein the first switch, the second switch, and the third switch are transistors.

5. The small-power charging device according to claim 2, wherein the first MOS transistor, the second MOS transistor, and the third MOS transistor are P-MOS transistors.

6. The small-charge charging device according to claim 2, wherein the third resistor, the fourth resistor, and the fifth resistor are pull-up resistors.

7. The small-power charging device as claimed in claim 2, wherein the first resistor has a resistance of 100 to 1000K Ω, and the second resistor has a resistance of 1 to 10 Ω.

8. The small-charge charging device according to claim 2, wherein the connector receives 5V dc power.