CN217469482U - Multi-gear constant-current automatic charging circuit - Google Patents
Multi-gear constant-current automatic charging circuit Download PDFInfo
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- CN217469482U CN217469482U CN202220444713.7U CN202220444713U CN217469482U CN 217469482 U CN217469482 U CN 217469482U CN 202220444713 U CN202220444713 U CN 202220444713U CN 217469482 U CN217469482 U CN 217469482U
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Abstract
The utility model discloses a multi-gear constant current automatic charging circuit, which comprises a DC-DC conversion circuit, an output current regulating circuit, an output switch circuit, a battery temperature acquisition circuit, a battery voltage acquisition circuit, an MCU processor and a charging interface; the output end of the DC-DC conversion circuit is connected with the charging interface through the output switch circuit; the MCU processor is connected with the DC-DC conversion circuit through the output current regulating circuit, is connected with the output switch circuit and controls the on-off of the output switch circuit, and is connected with the charging interface through the battery temperature acquisition circuit and the battery voltage acquisition circuit. The utility model discloses have many grades of output current, and export when exporting every grade of output current stably to can avoid damaging rechargeable battery.
Description
Technical Field
The utility model relates to a field of charging especially indicates a many grades of constant current automatic charging circuit.
Background
The rechargeable battery is a recyclable battery, and the charging current is adjusted according to the state of the rechargeable battery in the charging process of the rechargeable battery, so that the service life and the charging efficiency of the rechargeable battery are ensured. However, the charging current stability of the existing charging circuit to the battery is not good, and the charging circuit can damage the rechargeable battery.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a many grades of constant current automatic charging circuit to overcome not enough among the prior art.
In order to achieve the above purpose, the solution of the present invention is:
a multi-gear constant-current automatic charging circuit comprises a DC-DC conversion circuit, an output current regulating circuit, an output switch circuit, a battery temperature acquisition circuit, a battery voltage acquisition circuit, an MCU (microprogrammed control unit) processor and a charging interface; the output end of the DC-DC conversion circuit is connected with the charging interface through an output switch circuit; the MCU processor is connected with the DC-DC conversion circuit through the output current regulating circuit, is connected with the output switch circuit and controls the on-off of the output switch circuit, and is connected with the charging interface through the battery temperature acquisition circuit and the battery voltage acquisition circuit; the output current regulating circuit comprises an operational amplifier, a feedback resistor, a feedback capacitor, a positive end resistor, a negative end resistor and a negative end voltage regulating circuit; the in-phase input end of the operational amplifier is connected with the first end of the positive end resistor, the second end of the positive end resistor is grounded, the inverting input end of the operational amplifier is connected with the first end of the feedback resistor and the first end of the negative end resistor, the second end of the negative end resistor is connected with the MCU processor through the negative end voltage regulating circuit, the second end of the feedback resistor is connected with the first end of the feedback capacitor, the second end of the feedback capacitor is connected with the output end of the operational amplifier, and the output end of the operational amplifier is connected with the DC-DC conversion circuit through the output diode.
The negative end voltage regulating circuit comprises a negative end input resistor, a first negative end regulating resistor, a second negative end regulating resistor, a third negative end regulating resistor, a first regulating triode and a second regulating triode; the second end of negative terminal resistance is connected with the first end of negative terminal input resistance, the first end of first negative terminal adjusting resistance, the first end of second negative terminal adjusting resistance and the first end of third negative terminal adjusting resistance, the second end of negative terminal input resistance is connected with the control power supply, the second end of first negative terminal adjusting resistance is grounded, the second end of second negative terminal adjusting resistance is grounded through the first adjusting triode, the second end of third negative terminal adjusting resistance is grounded through the second adjusting triode, the base electrodes of the first adjusting triode and the second adjusting triode are connected with the MCU processor.
The multi-gear constant-current automatic charging circuit also comprises a control power supply circuit; the control power supply circuit comprises a voltage stabilizing chip, a VIN pin of the voltage stabilizing chip is connected with the anode of a charging interface through a first input diode, the VIN pin of the voltage stabilizing chip is also connected with the input end of the DC-DC conversion circuit through a second input diode and an input inductor, and a VOUT pin of the voltage stabilizing chip is used for outputting a control power supply.
The DC-DC conversion circuit comprises a DC-DC conversion chip, a first input resistor, a second input resistor, a third input resistor, a first input capacitor, a second input capacitor, an output inductor, a first output resistor, a second output resistor, a third output resistor, a first output capacitor, a second output capacitor and a third output capacitor; a VIN pin of the DC-DC conversion chip is connected with a first end of a first input resistor, a second end of a second input resistor, a first end of a third input resistor, a first end of a first input capacitor and an anode of a second input capacitor and is used as an input end of the DC-DC conversion circuit, an input end of the DC-DC conversion circuit is connected with an input end of the DC-DC conversion circuit, a PG pin of the DC-DC conversion chip is connected with a second end of the second input resistor, a PGND pin and an SGND pin of the DC-DC conversion chip, a second end of the first input resistor, a second end of the first input capacitor and a cathode of the second input capacitor are grounded, an EN pin of the DC-DC conversion chip is connected with a second end of the third input resistor, an LX pin of the DC-DC conversion chip is connected with a first end of an output inductor and a first end of a first output capacitor, and a second end of the first output capacitor is grounded through a third output resistor, the second end of the output inductor is connected with the first end of the first output resistor, the first end of the second output capacitor and the first end of the third output capacitor and serves as the output end of the DC-DC conversion circuit, the output end of the DC-DC conversion circuit is connected with the charging interface through the output switch circuit, the FB pin of the DC-DC conversion chip is connected with the second end of the first output resistor, the first end of the second output resistor and the second end of the second output capacitor, and the second end of the second output capacitor and the second end of the second output resistor are grounded; and the output end of the operational amplifier of the output current regulating circuit is connected with an FB pin of a DC-DC conversion chip of the DC-DC conversion circuit through an output diode.
The multi-gear constant-current automatic charging circuit further comprises a circuit temperature acquisition circuit connected with the MCU processor.
The circuit temperature acquisition circuit comprises a thermistor.
The multi-gear constant-current automatic charging circuit further comprises a state indicating circuit connected with the MCU processor.
The status indication circuit includes an indicator light.
A first TVS tube is connected between the positive electrode pin and the negative electrode pin of the charging interface, and a second TVS tube is connected between the temperature acquisition pin and the negative electrode pin of the charging interface.
The multi-gear constant-current automatic charging circuit further comprises a direct-current input circuit, and the direct-current input circuit is connected with the input end of the DC-DC conversion circuit through a pi-type filter.
After the technical scheme is adopted, the utility model discloses an output current regulating circuit adjusts the utility model discloses an output current, and according to "virtual weak point" and "virtual disconnected" circuit principle, the reverse phase input voltage that MCU treater was put through control output current regulating circuit's fortune alright adjust output current regulating circuit's output current and make output current stable, and then adjust DC-DC converting circuit's output current and make this output current stable, thereby make the utility model discloses output is stable when having many grades of output current and exporting every grade of output current to avoid damaging rechargeable battery.
Drawings
Fig. 1 is a schematic circuit diagram of the present invention.
Detailed Description
In order to further explain the technical solution of the present invention, the present invention is explained in detail by the following embodiments.
As shown in fig. 1, the utility model discloses a multi-gear constant current automatic charging circuit, which comprises a DC-DC conversion circuit, an output current regulating circuit, an output switch circuit, a battery temperature collecting circuit, a battery voltage collecting circuit, an MCU processor IC601 and a charging interface; the output end of the DC-DC conversion circuit is connected with the charging interface through an output switch circuit; the MCU processor IC601 is connected with the DC-DC conversion circuit through the output current regulating circuit, the MCU processor IC601 is connected with the output switch circuit and controls the on-off of the output switch circuit, and the MCU processor IC601 is connected with the charging interface through the battery temperature acquisition circuit and the battery voltage acquisition circuit. The battery temperature acquisition circuit is connected with a thermistor in the rechargeable battery through a charging interface to acquire the temperature of the rechargeable battery, the battery voltage acquisition circuit is connected with the anode of the rechargeable battery through the charging interface to acquire the voltage of the rechargeable battery, and the MCU processor IC601 can adopt EM88F752NASO16UJ of Yilong electron.
The utility model discloses a theory of operation does: the MCU processor IC601 acquires the temperature and the voltage of the battery through the battery temperature acquisition circuit and the battery voltage acquisition circuit and controls the output current regulation circuit and the output switch circuit according to the acquired temperature and voltage information of the battery, so that the utility model can output different currents to the rechargeable battery according to different states of the rechargeable battery, and the charging effect of the rechargeable battery is ensured; additionally the utility model discloses can stop to charge for the battery through turn-OFF output switch circuit when the output is excessive pressure (when rechargeable battery's voltage is too high promptly), realize exporting overvoltage protection, guarantee that the battery can not damage.
In the present invention, the output current regulating circuit includes an operational amplifier IC401, a feedback resistor R401, a feedback capacitor C401, a positive end resistor R403, a negative end resistor R404, and a negative end voltage regulating circuit; the non-inverting input end of the operational amplifier IC401 is connected with the first end of a positive end resistor R403, the second end of the positive end resistor R403 is grounded, the inverting input end of the operational amplifier IC401 is connected with the first end of a feedback resistor R401 and the first end of a negative end resistor R404, the second end of the negative end resistor R404 is connected with the MCU processor IC601 through a negative end voltage regulating circuit, the second end of the feedback resistor R401 is connected with the first end of a feedback capacitor C401, the second end of the feedback capacitor C401 is connected with the output end of the operational amplifier IC401, and the output end of the operational amplifier IC401 is connected with a DC-DC conversion circuit through an output diode D302. The working principle of the output current regulating circuit is as follows: according to the circuit principle of "virtual weak point" and "virtual disconnected", MCU treater IC601 just can adjust output current regulating circuit's output current and make output current stable through control fortune anti-phase input voltage of putting IC401, and then adjusts DC-DC converting circuit's output current and makes this output current stable, thereby makes the utility model discloses output is stable when having many grades of output current and exporting every grade of output current to avoid damaging rechargeable battery.
In the present invention, the negative terminal voltage adjusting circuit includes a negative terminal input resistor R405, a first negative terminal adjusting resistor R408, a second negative terminal adjusting resistor R409, a third negative terminal adjusting resistor R410, a first adjusting triode Q401, and a second adjusting triode Q402; the second end of the negative terminal resistor R404 is connected with the first end of the negative terminal input resistor R405, the first end of the first negative terminal adjusting resistor R408, the first end of the second negative terminal adjusting resistor R409 and the first end of the third negative terminal adjusting resistor R410, the second end of the negative terminal input resistor R405 is connected with the control power VREF, the second end of the first negative terminal adjusting resistor R408 is grounded, the second end of the second negative terminal adjusting resistor R409 is grounded through the first adjusting triode Q401, the second end of the third negative terminal adjusting resistor R410 is grounded through the second adjusting triode Q402, and bases of the first adjusting triode Q401 and the second adjusting triode Q402 are connected with the MCU processor IC 601. The MCU processor IC601 controls whether the second negative terminal adjusting resistor R409 and the third negative terminal adjusting resistor R410 are connected in parallel with the first negative terminal adjusting resistor R407 by controlling the on/off of the first adjusting transistor Q401 and the second adjusting transistor Q402, thereby controlling the voltage at the inverting input terminal of the operational amplifier IC 401.
In the present invention, the DC-DC conversion circuit includes a DC-DC conversion chip IC301, a first input resistor R301, a second input resistor R302, a third input resistor R303, a first input capacitor C301, a second input capacitor EC301, an output inductor L301, a first output resistor R304, a second output resistor R306, a third output resistor R307, a first output capacitor C303, a second output capacitor C304, and a third output capacitor C305; the DC-DC conversion chip IC301 may adopt DIO6083CN8 of esot microelectronics, a VIN pin of the DC-DC conversion chip IC301 is connected to a first end of the first input resistor R301, a second end of the second input resistor R302, a first end of the third input resistor R303, a first end of the first input capacitor C301 and an anode of the second input capacitor EC301 and serves as an input end of the DC-DC conversion circuit, an input end of the DC-DC conversion circuit is connected to an input end of the DC-DC conversion circuit, a PG pin of the DC-DC conversion chip IC301 is connected to a second end of the second input resistor R302, a PGND pin and an SGND pin of the DC-DC conversion chip IC301, a second end of the first input resistor R301, a second end of the first input capacitor C301 and a cathode of the second input capacitor EC301 are grounded, a pin of the DC-DC conversion chip IC301 is connected to a second end of the third input resistor R303, and an LX pin of the DC-DC conversion chip IC301 is connected to a first end of the output inductor L301, A first end of the first output capacitor C303, a second end of the first output capacitor C303 is grounded through a third output resistor R307, a second end of the output inductor L301 is connected to the first end of the first output resistor R304, the first end of the second output capacitor C304 and the first end of the third output capacitor C305 and serves as an output end of the DC-DC conversion circuit, the output end of the DC-DC conversion circuit is connected to the charging interface through an output switch circuit, an FB pin of the DC-DC conversion chip IC301 is connected to the second end of the first output resistor R304, the first end of the second output resistor R306 and the second end of the second output capacitor C304, and the second end of the second output capacitor C304 and the second end of the second output resistor R306 are grounded; the output end of the operational amplifier IC401 of the output current regulating circuit is connected with the FB pin of the DC-DC conversion chip IC301 of the DC-DC conversion circuit through an output diode D302, so as to regulate the output current of the DC-DC conversion.
The utility model discloses in, be connected with first TVS pipe ESD1 between the positive pole pin of the interface that charges and the negative pole pin, be connected with second TVS pipe ESD2 between the temperature acquisition pin of the interface that charges and the negative pole pin, first TVS pipe ESD1 and second TVS pipe ESD2 can be with static leading-in ground, thereby make the utility model discloses good ESD performance has.
In the utility model, the multi-gear constant current automatic charging circuit of the utility model also comprises a control power supply circuit; the control power supply circuit comprises a voltage stabilizing chip IC501, a VIN pin of the voltage stabilizing chip IC501 is connected with the anode of a charging interface through a first input diode D501, the VIN pin of the voltage stabilizing chip IC501 is also connected with the input end of the DC-DC conversion circuit through a second input diode D502 and an input inductor L501, and a VOUT pin of the voltage stabilizing chip IC501 is used for outputting a control power VREF. When the multi-gear constant-current automatic charging circuit starts to work, the voltage stabilizing chip IC501 is connected to the input end voltage of the DC-DC conversion circuit to output a control power supply VREF; and be in the utility model discloses a steady during operation steady voltage chip IC501 of many grades of constant current automatic charging circuit inserts the utility model discloses a many grades of constant current automatic charging circuit's output voltage and output more are stable control power VREF.
The utility model discloses in, the utility model discloses an automatic charging circuit of many grades of constant currents still includes the circuit temperature acquisition circuit who is connected with MCU treater IC601, and MCU treater IC601 can acquire through circuit temperature acquisition circuit the utility model discloses an automatic charging circuit's of many grades of constant currents temperature the utility model discloses a many grades of automatic charging circuit of constant currents temperature can turn off output switch circuit and stop to charge for rechargeable battery when too high and realize the input overtemperature prote, guarantee the utility model discloses an automatic charging circuit of many grades of constant currents and battery can not damage. The circuit temperature acquisition circuit can include thermistor NTC, the utility model discloses a thermistor NTC's voltage variation acquires the utility model discloses a many grades of constant current automatic charging circuit's temperature realizes with low costs.
The utility model discloses in, the utility model discloses an automatic charging circuit of many grades of constant currents still includes the state indication circuit who is connected with MCU treater IC 601. The MCU processor IC601 prompts the user through the state indicating circuit for the state of the multi-gear constant-current automatic charging circuit and the charging battery; this status indication circuit can include pilot lamp LED601, the utility model discloses a user is reminded to the different lighting effect of pilot lamp LED601, realizes with low costs.
The utility model discloses in, the utility model discloses an automatic charging circuit of many grades of constant currents still includes direct current input circuit, direct current input circuit passes through pi type filter and connects DC-DC converting circuit's input and can effectively reduce the utility model discloses an automatic charging circuit's of many grades of constant currents inrush current.
The above embodiments and drawings are not intended to limit the form and style of the present invention, and any suitable changes or modifications made by those skilled in the art should not be construed as departing from the scope of the present invention.
Claims (10)
1. A multi-gear constant-current automatic charging circuit is characterized in that: the device comprises a DC-DC conversion circuit, an output current regulating circuit, an output switch circuit, a battery temperature acquisition circuit, a battery voltage acquisition circuit, an MCU (microprogrammed control unit) processor and a charging interface;
the output end of the DC-DC conversion circuit is connected with the charging interface through an output switch circuit; the MCU processor is connected with the DC-DC conversion circuit through the output current regulating circuit, is connected with the output switch circuit and controls the on-off of the output switch circuit, and is connected with the charging interface through the battery temperature acquisition circuit and the battery voltage acquisition circuit;
the output current regulating circuit comprises an operational amplifier, a feedback resistor, a feedback capacitor, a positive end resistor, a negative end resistor and a negative end voltage regulating circuit; the in-phase input end of the operational amplifier is connected with the first end of the positive end resistor, the second end of the positive end resistor is grounded, the inverting input end of the operational amplifier is connected with the first end of the feedback resistor and the first end of the negative end resistor, the second end of the negative end resistor is connected with the MCU processor through the negative end voltage regulating circuit, the second end of the feedback resistor is connected with the first end of the feedback capacitor, the second end of the feedback capacitor is connected with the output end of the operational amplifier, and the output end of the operational amplifier is connected with the DC-DC conversion circuit through the output diode.
2. The multi-stage constant current automatic charging circuit of claim 1, wherein: the negative end voltage regulating circuit comprises a negative end input resistor, a first negative end regulating resistor, a second negative end regulating resistor, a third negative end regulating resistor, a first regulating triode and a second regulating triode; the second end of negative terminal resistance is connected with the first end of negative terminal input resistance, the first end of first negative terminal adjusting resistance, the first end of second negative terminal adjusting resistance and the first end of third negative terminal adjusting resistance, the second end of negative terminal input resistance is connected with the control power supply, the second end of first negative terminal adjusting resistance is grounded, the second end of second negative terminal adjusting resistance is grounded through the first adjusting triode, the second end of third negative terminal adjusting resistance is grounded through the second adjusting triode, the base electrodes of the first adjusting triode and the second adjusting triode are connected with the MCU processor.
3. The multi-stage constant current automatic charging circuit according to claim 2, wherein: the power supply circuit also comprises a control power supply circuit; the control power supply circuit comprises a voltage stabilizing chip, a VIN pin of the voltage stabilizing chip is connected with the anode of a charging interface through a first input diode, the VIN pin of the voltage stabilizing chip is also connected with the input end of the DC-DC conversion circuit through a second input diode and an input inductor, and a VOUT pin of the voltage stabilizing chip is used for outputting a control power supply.
4. The multi-stage constant current automatic charging circuit according to claim 1, wherein: the DC-DC conversion circuit comprises a DC-DC conversion chip, a first input resistor, a second input resistor, a third input resistor, a first input capacitor, a second input capacitor, an output inductor, a first output resistor, a second output resistor, a third output resistor, a first output capacitor, a second output capacitor and a third output capacitor; a VIN pin of the DC-DC conversion chip is connected with a first end of a first input resistor, a second end of a second input resistor, a first end of a third input resistor, a first end of a first input capacitor and an anode of a second input capacitor and is used as an input end of the DC-DC conversion circuit, an input end of the DC-DC conversion circuit is connected with an input end of the DC-DC conversion circuit, a PG pin of the DC-DC conversion chip is connected with a second end of the second input resistor, a PGND pin and an SGND pin of the DC-DC conversion chip, a second end of the first input resistor, a second end of the first input capacitor and a cathode of the second input capacitor are grounded, an EN pin of the DC-DC conversion chip is connected with a second end of the third input resistor, an LX pin of the DC-DC conversion chip is connected with a first end of an output inductor and a first end of a first output capacitor, and a second end of the first output capacitor is grounded through a third output resistor, the second end of the output inductor is connected with the first end of the first output resistor, the first end of the second output capacitor and the first end of the third output capacitor and serves as the output end of the DC-DC conversion circuit, the output end of the DC-DC conversion circuit is connected with the charging interface through the output switch circuit, the FB pin of the DC-DC conversion chip is connected with the second end of the first output resistor, the first end of the second output resistor and the second end of the second output capacitor, and the second end of the second output capacitor and the second end of the second output resistor are grounded;
and the output end of the operational amplifier of the output current regulating circuit is connected with an FB pin of a DC-DC conversion chip of the DC-DC conversion circuit through an output diode.
5. The multi-stage constant current automatic charging circuit according to claim 1, wherein: the circuit temperature acquisition circuit is connected with the MCU processor.
6. The multi-stage constant current automatic charging circuit according to claim 5, wherein: the circuit temperature acquisition circuit comprises a thermistor.
7. The multi-stage constant current automatic charging circuit according to claim 1, wherein: the MCU processing unit also comprises a state indicating circuit connected with the MCU processor.
8. The multi-stage constant current automatic charging circuit according to claim 7, wherein: the status indication circuit includes an indicator light.
9. The multi-stage constant current automatic charging circuit according to claim 1, wherein: a first TVS tube is connected between the positive electrode pin and the negative electrode pin of the charging interface, and a second TVS tube is connected between the temperature acquisition pin and the negative electrode pin of the charging interface.
10. The multi-stage constant current automatic charging circuit according to claim 1, wherein: the DC-DC conversion circuit further comprises a DC input circuit, and the DC input circuit is connected with the input end of the DC-DC conversion circuit through a pi-type filter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220444713.7U CN217469482U (en) | 2022-03-03 | 2022-03-03 | Multi-gear constant-current automatic charging circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220444713.7U CN217469482U (en) | 2022-03-03 | 2022-03-03 | Multi-gear constant-current automatic charging circuit |
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| Publication Number | Publication Date |
|---|---|
| CN217469482U true CN217469482U (en) | 2022-09-20 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202220444713.7U Active CN217469482U (en) | 2022-03-03 | 2022-03-03 | Multi-gear constant-current automatic charging circuit |
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| Country | Link |
|---|---|
| CN (1) | CN217469482U (en) |
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- 2022-03-03 CN CN202220444713.7U patent/CN217469482U/en active Active
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