Novel charging protection circuit
By designing a charging protection system including power supply, DC input, voltage stabilization, control and DC output circuits, the problem of abnormal charging and damage of lithium batteries in existing charging technologies is solved, a safe and normal charging process is achieved, and a visual indication of charging status is provided.
Patent Information
- Application Number
- CN202421657483.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-14
- Publication Date
- 2025-06-27
- Estimated Expiration
- 2034-07-14
AI Technical Summary
Existing charging technology is difficult to effectively protect lithium batteries, resulting in abnormal charging or damage to lithium batteries, and may even cause fires.
A new type of charging protection circuit is designed, including power supply circuit, DC input circuit, voltage stabilization circuit, control circuit and DC output circuit. The microcontroller controls the chip and voltage stabilization tube and other components are used to detect the charger output voltage and pulses, and determine whether the correct charger is inserted through the identification protection circuit to ensure safe charging.
It effectively prevents the damage and fire risks of lithium batteries caused by wrong chargers, ensures the safety and normal progress of the charging process, and provides visual indications of the charging status.
Smart Images
Figure CN223039689U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of charging, and particularly relates to a novel charging protection circuit. Background Art
[0002] If a wrong charger is used to charge a lithium battery, it cannot be charged normally, or the lithium battery will be damaged, or even catch fire. By specially setting the voltage signal output by a dedicated charger and adopting a dedicated identification protection circuit, protection control is carried out for charging the lithium battery. Only when the correct dedicated charger is inserted can the identification protection circuit start charging. If a wrong charger is inserted, the identification protection circuit cuts off the charging current, cannot start charging, and at the same time emits a warning indicator light.
[0003] Therefore, in view of the above problems, the existing charging technology needs to be further improved. Summary of the Utility Model
[0004] The purpose of the utility model is to overcome the problems of abnormal charging and damage to lithium batteries in the prior art.
[0005] The technical solution of the utility model is specifically as follows:
[0006] A novel charging protection circuit, the charging protection circuit includes: a power supply circuit, a DC input circuit, a voltage stabilizing circuit, a control circuit, and a DC output circuit. The output end of the power supply circuit is connected to the input end of the DC input circuit, the output end of the DC input circuit is connected to the input end of the voltage stabilizing circuit, the output end of the voltage stabilizing circuit is connected to the input end of the control circuit, the output end of the control circuit is connected to the input end of the DC output circuit, and the output end of the DC output circuit outputs externally;
[0007] Among them, the control circuit includes a single-chip microcomputer control chip.
[0008] Further, the power supply circuit includes a power input circuit, a rectification and filtering circuit, a power transformer circuit, a power control circuit, and a power output circuit. The input end of the power input circuit is connected to an external AC power supply, the output end of the power input circuit is connected to the input end of the rectification and filtering circuit, the output end of the rectification and filtering circuit is connected to the input end of the power transformer circuit, the output end of the power transformer circuit is respectively connected to the input end of the power control circuit and the input end of the power output circuit, and the output end of the power output circuit is connected to the input end of the DC input circuit.
[0009] Further, the DC input circuit includes a fuse F1, a resistor R12, and a diode D1. One end of the fuse F1 is connected to the output end of the power supply circuit, and the other end of the fuse F1 is connected to the control end of the DC output circuit. One end of the resistor R12 is connected to the output end of the power supply circuit, and the other end of the resistor R12 is connected to the positive electrode of the diode D1. The negative electrode of the diode D1 is connected to the input end of the voltage stabilizing circuit.
[0010] Further, the voltage stabilizing circuit includes a three-terminal voltage regulator U2 and a voltage stabilizing diode DW. The input ends of the three-terminal voltage regulator U2 and the voltage stabilizing diode DW are commonly connected to the output end of the DC input circuit. The grounding ends of the three-terminal voltage regulator U2 and the voltage stabilizing diode DW are commonly grounded. The output end of the three-terminal voltage regulator U2 is connected to the input end of the control circuit.
[0011] Further, the voltage stabilizing circuit further includes a capacitor C1, a resistor R2, a capacitor C3, and a capacitor C2. One end of the capacitor C1 is connected in parallel to one end of the resistor R2 and the output end of the DC input circuit, and the other end of the capacitor C1 is grounded. The other end of the resistor R2 is connected in parallel to the input end of the three-terminal voltage regulator U2, one end of the capacitor C2, and the negative electrode of the voltage stabilizing diode DW. The other end of the capacitor C2 and the positive electrode of the voltage stabilizing diode DW are commonly grounded. The grounding end of the voltage regulator U2 is grounded. The output end of the voltage regulator U2 is connected in parallel to one end of the capacitor C3 and the input end of the control circuit, and the other end of the capacitor C3 is grounded.
[0012] Further, the control circuit includes a single-chip microcomputer U1, a capacitor C4, a capacitor C5, a resistor R14, a resistor R13, a resistor R11, a light-emitting diode D2, and a light-emitting diode D3. The "1" terminal of the single-chip microcomputer U1 is grounded. The "3" terminal of the single-chip microcomputer U1 is connected to one end of the resistor R13, and the other end of the resistor R13 is connected to the positive electrode of the light-emitting diode D2, and the negative electrode of the light-emitting diode D2 is grounded. The "9" terminal of the single-chip microcomputer U1 is connected in parallel to one end of the input end of the DC output circuit and one end of the resistor R11, and the other end of the resistor R11 is connected to the positive electrode of the light-emitting diode D3, and the negative electrode of the light-emitting diode D3 is grounded. The "10" terminal of the single-chip microcomputer U1 is connected to one end of the resistor R14 and the second end of the input end of the DC output circuit. The "13" terminal of the single-chip microcomputer U1 is connected to one end of the capacitor C5 and the third end of the input end of the DC output circuit, and the other end of the capacitor C5 is grounded. The "16" terminal of the single-chip microcomputer U1 is connected to the other end of the resistor R14 and one end of the capacitor C4, and the other end of the capacitor C4 is grounded.
[0013] Further, the DC output circuit includes a PMOS transistor Q1 and an NPN transistor Q2. The base of the NPN transistor Q2 is connected to the output terminal of the control circuit. The emitter of the NPN transistor Q2 is grounded. The collector of the NPN transistor Q2 is connected to the gate of the PMOS transistor Q1. The drain of the PMOS transistor Q1 serves as the output terminal. The source of the PMOS transistor Q1 is connected to the output terminal of the DC input circuit.
[0014] Further, the DC output circuit further includes a resistor R9, a resistor R8, a resistor R10, a resistor R15, a resistor R7, a resistor R1, a resistor R3, a resistor R4, a resistor R5, a resistor R6, an interface DC-out, and a capacitor C6. One end of the resistor R9, one end of the resistor R8, and one end of the resistor R10 are respectively connected to the output terminal of the control circuit. The other end of the resistor R9 is connected to the "2" terminal of the interface DC-out. The other end of the resistor R8 is connected to the "1" terminal of the interface DC-out and one end of the resistor R1. The other end of the resistor R1 is grounded. The other end of the resistor R10 is connected to the base of the NPN transistor Q2. The emitter of the NPN transistor Q2 is grounded. The collector of the NPN transistor Q2 is connected to one end of the resistor R15. The other end of the resistor R15 is connected to the gate of the PMOS transistor Q1 and one end of the resistor R7. The other end of the resistor R7 is connected to one end of the resistor R3, the source of the PMOS transistor Q1, and the output terminal of the DC input circuit. The drain of the PMOS transistor Q1 is connected to the "3" terminal of the interface DC-out. The other end of the resistor R3 is connected to one end of the resistor R4. The other end of the resistor R4 is connected to one end of the resistor R5 and one end of the resistor R6. The other end of the resistor R6 is connected to one end of the capacitor C6. The other end of the capacitor C6 and the other end of the resistor R5 are commonly grounded.
[0015] Further, the power input circuit includes a fuse F01, a capacitor CX01, a mutual inductor T01, and a capacitor CX02. One end of the fuse F01 is connected to the AC live wire. The other end of the fuse F01 is connected in parallel to one end of the capacitor CX01 and one end of the input terminal of the mutual inductor T01. The other end of the capacitor CX01 and the other end of the input terminal of the mutual inductor T01 are commonly connected to the AC neutral wire. One end of the output terminal of the mutual inductor T01 is connected in parallel to one end of the input terminal of the rectifier filter circuit and one end of the capacitor CX02. The other end of the output terminal of the mutual inductor T01 is connected in parallel to the other end of the input terminal of the rectifier filter circuit and the other end of the capacitor CX02.
[0016] Further, the rectifying and filtering circuit includes a rectifier bridge BD1, an inductor L1, a resistor R02, a capacitor C01, a capacitor C02, an inductor L2, a resistor R03, a resistor R04, a capacitor C06, and a diode D03. One end of the output terminal of the power input circuit is connected to one end of the input terminal of the rectifier bridge BD1, and the other end of the output terminal of the power input circuit is connected to the other end of the input terminal of the rectifier bridge BD1. One end of the output terminal of the rectifier bridge BD1 is connected in parallel to one end of the inductor L1, one end of the resistor R02, and one end of the capacitor C01. The other end of the output terminal of the rectifier bridge BD1 is connected in parallel to one end of the inductor L2 and the other end of the capacitor C01. The other end of the inductor L2 is connected in parallel to one end of the capacitor C02 and one end of the power control circuit. The other end of the capacitor C02 is connected in parallel to the other end of the inductor L1, the other end of the resistor R02, one end of the resistor R03, one end of the capacitor C06, and one end of the input terminal of the power transformer circuit. The other end of the resistor R03 is connected to the other end of the capacitor C06 and one end of the resistor R04. The other end of the resistor R04 is connected to the negative electrode of the diode D03, and the positive electrode of the diode D03 is connected to the other end of the input terminal of the power transformer circuit.
[0017] Further, the power transformer circuit includes a transformer T02. One end of the output terminal of the rectifying and filtering circuit is connected to one end of the input terminal of the transformer T02, and the other end of the output terminal of the rectifying and filtering circuit is connected to the other end of the input terminal of the transformer T02. One end of the second output coil of the transformer T02 is connected to one end of the power control circuit, and the other end of the second output coil of the transformer T02 is connected to the other end of the power control circuit. One end of the first output coil of the transformer T02 is connected to the input terminal of the power output circuit, and the other end of the first output coil of the transformer T02 is grounded.
[0018] Further, the power control circuit includes a resistor R01, an NMOS transistor Q01, a capacitor CY, a chip U01, a capacitor C07, a resistor R09, a capacitor C05, a diode D02, a resistor R05, a resistor R06, a resistor R07, and a resistor R08. The other end of the input terminal of the power transformer circuit is connected to the drain of the NMOS transistor Q01. The gate of the NMOS transistor Q01 is connected to the "2" terminal of the chip U01. The source of the NMOS transistor Q01 is connected to the "3" terminal of the chip U01 and the other end of the resistor R01. The other end of the capacitor CY is grounded. The "4" terminal of the chip U01 is connected to the other end of the capacitor C07. The "5" terminal of the chip U01 is connected to one end of the resistor R08 and one end of the resistor R07. The "6" terminal of the chip U01 is connected to one end of the capacitor C05 and one end of the resistor R09. The other end of the capacitor C05 and the other end of the resistor R08 are commonly connected to the "1" terminal of the chip U01. One end of the capacitor C07 is connected to one end of the second output coil of the transformer T02. The other end of the resistor R09 is connected to the negative electrode of the diode D02. The positive electrode of the diode D02 is connected to the other end of the second output coil of the transformer T02. The other end of the resistor R07 is connected to the other end of the second output coil of the transformer T02. One end of the first output coil of the transformer T02 is connected to one end of the resistor R010 and the positive electrode of the diode D01. The other end of the resistor R010 is connected to one end of the capacitor C04. The other end of the capacitor C04 is connected to the negative electrode of the diode D01, one end of the capacitor C03, and the output terminal. The other end of the capacitor C03 is grounded. One end of the resistor R05 is connected to one end of the input terminal of the transformer T02. The other end of the resistor R05 is connected to one end of the resistor R06. The other end of the resistor R06 is connected to one end of the capacitor C05.
[0019] Further, the power output circuit includes a capacitor C04, a capacitor C03, a resistor R010, and a diode D01. One end of the first output coil of the transformer T02 is connected to one end of the resistor R010 and the positive electrode of the diode D01. The other end of the resistor R010 is connected to one end of the capacitor C04. The other end of the capacitor C04 is connected to the negative electrode of the diode D01, one end of the capacitor C03, and the output terminal. The other end of the capacitor C03 is grounded.
[0020] Further, specifically: The power supply circuit includes a fuse F01, a capacitor CX01, a mutual inductor T01, a capacitor CX02, a rectifier bridge BD1, an inductor L1, a resistor R02, a capacitor C01, a capacitor C02, an inductor L2, a resistor R01, a resistor R03, a resistor R04, a capacitor C06, a diode D03, an NMOS transistor Q01, a capacitor CY, a transformer T02, a chip U01, a capacitor C07, a resistor R09, a capacitor C05, a diode D02, a capacitor C04, a capacitor C03, a resistor R010, a diode D01, a resistor R05, a resistor R06, a resistor R07, and a resistor R08. One end of the fuse F01 is connected to the AC live wire, and the other end of the fuse F01 is connected in parallel to one end of the capacitor CX01 and one end of the input of the mutual inductor T01. The other end of the capacitor CX01 and the other end of the input of the mutual inductor T01 are commonly connected to the AC neutral wire. One end of the output of the mutual inductor T01 is connected in parallel to one end of the input of the rectifier bridge BD1 and one end of the capacitor CX02. The other end of the output of the mutual inductor T01 is connected in parallel to the other end of the input of the rectifier bridge BD1 and the other end of the capacitor CX02. One end of the output of the rectifier bridge BD1 is connected in parallel to one end of the inductor L1, one end of the resistor R02, and one end of the capacitor C01. The other end of the output of the rectifier bridge BD1 is connected in parallel to one end of the inductor L2 and the other end of the capacitor C01. The other end of the inductor L2 is connected in parallel to one end of the capacitor C02, one end of the capacitor C07, one end of the capacitor CY, one end of the resistor R01, and the "1" terminal of the chip U01. The other end of the capacitor C02 is connected in parallel to the other end of the inductor L1, the other end of the resistor R02, one end of the resistor R03, one end of the capacitor C06, and one end of the input of the transformer T02. The other end of the resistor R03 is connected to the other end of the capacitor C06 and one end of the resistor R04. The other end of the resistor R04 is connected to the negative electrode of the diode D03. The positive electrode of the diode D03 is connected to the drain of the NMOS transistor Q01 and the other end of the input of the transformer T02. The gate of the NMOS transistor Q01 is connected to the "2" terminal of the chip U01. The source of the NMOS transistor Q01 is connected to the "3" terminal of the chip U01 and the other end of the resistor R01. The other end of the capacitor CY is grounded. The "4" terminal of the chip U01 is connected to the other end of the capacitor C07. The "5" terminal of the chip U01 is connected to one end of the resistor R08 and one end of the resistor R07. The "6" terminal of the chip U01 is connected to one end of the capacitor C05 and one end of the resistor R09. The other end of the capacitor C05 and the other end of the resistor R08 are commonly connected to the "1" terminal of the chip U01. One end of the capacitor C07 is connected to one end of the second output coil of the transformer T02. The other end of the resistor R09 is connected to the negative electrode of the diode D02. The positive electrode of the diode D02 is connected to the other end of the second output coil of the transformer T02. The other end of the resistor R07 is connected to the other end of the second output coil of the transformer T02. One end of the first output coil of the transformer T02 is connected to one end of the resistor R010 and the positive electrode of the diode D01.The other end of the resistor R010 is connected to one end of the capacitor C04. The other end of the capacitor C04 is connected to the negative electrode of the diode D01, one end of the capacitor C03, and the output terminal. The other end of the capacitor C03 is grounded. One end of the resistor R05 is connected to one end of the input terminal of the transformer T02. The other end of the resistor R05 is connected to one end of the resistor R06. The other end of the resistor R06 is connected to one end of the capacitor C05.,
[0021] Further, the charging protection circuit further includes a programming and writing circuit, and the output terminal of the programming and writing circuit is connected to the programming terminal of the control circuit.
[0022] Further, the programming and writing circuit includes a "write" interface and a capacitor C7. The "3" terminal and the "4" terminal of the "write" interface are respectively connected to the programming terminal of the control circuit. The "2" terminal of the "write" interface is grounded. The "1" terminal of the "write" interface is connected to one end of the capacitor C7 and the output terminal of the voltage stabilizing circuit. The other end of the capacitor C7 is grounded.
[0023] Beneficial effects
[0024] Through the design of the charging technology, the present utility model adopts a power supply circuit, a DC input circuit, a voltage stabilizing circuit, a control circuit, and a DC output circuit, and can achieve charging protection, etc. The highest voltage output by a common charger is an integer multiple of the saturation voltage of a lithium battery. The saturation voltage of a common single-section lithium-ion battery is 4.2V. When there is no starting charging current, the output voltage is an integer multiple of the stable lithium battery saturation voltage, 4.2V×N. The dedicated charger sets the output voltage to a relatively low specific voltage when there is no charging current, and at the same time makes the output voltage form a pulse with a specific width. The recognition protection circuit detects this voltage and pulse width. If it meets the set range, it is judged as correct, and then the charging control is started for normal charging, and at the same time, a normal charging indicator light is displayed. Otherwise, the charging current is turned off and an error indicator light signal is issued. Description of the drawings
[0025] Figure 1 It is a schematic structural diagram of a novel charging protection circuit of the present utility model.
[0026] Figure 2 It is a schematic structural diagram of the power supply circuit of a novel charging protection circuit of the present utility model.
[0027] Figure 3 It is a schematic structural diagram of the DC charging protection circuit of a novel charging protection circuit of the present utility model.
[0028] Description of the drawings: 01. Power supply circuit; 02. DC input circuit; 03. Voltage stabilizing circuit; 04. Control circuit; 05. DC output circuit. Specific implementation manners
[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.
[0030] Refer to Figures 1 - 3 As shown, a novel charging protection circuit provided by the present invention includes: a power supply circuit 01, a DC input circuit 02, a voltage stabilizing circuit 03, a control circuit 04, and a DC output circuit 05. Among them, the control circuit 04 includes a single-chip microcomputer control chip;
[0031] Among them, the output end of the power supply circuit 01 is connected to the input end of the DC input circuit 02, the output end of the DC input circuit 02 is connected to the input end of the voltage stabilizing circuit 03, the output end of the voltage stabilizing circuit 03 is connected to the input end of the control circuit 04, the output end of the control circuit 04 is connected to the input end of the DC output circuit 05, and the output end of the DC output circuit 05 outputs externally;
[0032] Among them, the power supply circuit 01 includes a power supply input circuit, a rectifying and filtering circuit, a power transformer circuit, a power control circuit, and a power output circuit. The input end of the power supply input circuit is connected to an external AC power supply, the output end of the power supply input circuit is connected to the input end of the rectifying and filtering circuit, the output end of the rectifying and filtering circuit is connected to the input end of the power transformer circuit, the output end of the power transformer circuit is respectively connected to the input end of the power control circuit and the input end of the power output circuit, and the output end of the power output circuit is connected to the input end of the DC input circuit 02;
[0033] Among them, the power supply input circuit includes a fuse F01, a capacitor CX01, a mutual inductor T01, and a capacitor CX02; the rectifying and filtering circuit includes a rectifier bridge BD1, an inductor L1, a resistor R02, a capacitor C01, a capacitor C02, an inductor L2, a resistor R03, a resistor R04, a capacitor C06, and a diode D03; the power transformer circuit includes a transformer T02; the power control circuit includes a resistor R01, an NMOS transistor Q01, a capacitor CY, a chip U01, a capacitor C07, a resistor R09, a capacitor C05, a diode D02, a resistor R05, a resistor R06, a resistor R07, and a resistor R08; the power output circuit includes a capacitor C04, a capacitor C03, a resistor R010, and a diode D01;
[0034] Among them, one end of the fuse F01 is connected to the AC live wire, and the other end of the fuse F01 is connected in parallel to one end of the capacitor CX01 and the "1" end of the mutual inductor T01. The other end of the capacitor CX01 and the "2" end of the mutual inductor T01 are commonly connected to the AC neutral wire. The "3" end of the mutual inductor T01 is connected in parallel to the "1" end of the rectifier bridge BD1 and one end of the capacitor CX02. The "4" end of the mutual inductor T01 is connected in parallel to the "2" end of the rectifier bridge BD1 and the other end of the capacitor CX02. The "3" of the rectifier bridge BD1 is connected in parallel to one end of the inductor L1, one end of the resistor R02, and one end (positive electrode) of the capacitor C01. The "4" end of the rectifier bridge BD1 is connected in parallel to one end of the inductor L2 and the other end (negative electrode) of the capacitor C01. The other end of the inductor L2 is connected in parallel to one end (negative electrode) of the capacitor C02, one end of the capacitor C07, one end of the capacitor CY, one end of the resistor R01, and the "1" terminal of the chip U01. The other end (positive electrode) of the capacitor C02 is connected in parallel to the other end of the inductor L1, the other end of the resistor R02, one end of the resistor R03, one end of the capacitor C06, and the "1" end of the transformer T02. The other end of the resistor R03 is connected to the other end of the capacitor C06 and one end of the resistor R04. The other end of the resistor R04 is connected to the negative electrode of the diode D03. The positive electrode of the diode D03 is connected to the drain of the NMOS transistor Q01 and the "2" end of the transformer T02. The gate of the NMOS transistor Q01 is connected to the "2" terminal of the chip U01. The source of the NMOS transistor Q01 is connected to the "3" terminal of the chip U01 and the other end of the resistor R01. The other end of the capacitor CY is grounded. The "4" terminal of the chip U01 is connected to the other end of the capacitor C07. The "5" terminal of the chip U01 is connected to one end of the resistor R08 and one end of the resistor R07. The "6" terminal of the chip U01 is connected to one end of the capacitor C05 and one end of the resistor R09. The other end of the capacitor C05 is commonly connected to the "1" terminal of the chip U01 with the other end of the resistor R08. One end of the capacitor C07 is connected to the "6" end of the transformer T02. The other end of the resistor R09 is connected to the negative electrode of the diode D02. The positive electrode of the diode D02 is connected to the "5" end of the transformer T02. The other end of the resistor R07 is connected to the "5" end of the transformer T02. The "3" end of the transformer T02 is connected to one end of the resistor R010 and the positive electrode of the diode D01. The other end of the resistor R010 is connected to one end of the capacitor C04. The other end of the capacitor C04 is connected to the negative electrode of the diode D01, one end (positive electrode) of the capacitor C03, and the output terminal DC-in. The other end of the capacitor C03 is grounded. One end of the resistor R05 is connected to the "1" end of the transformer T02. The other end of the resistor R05 is connected to one end of the resistor R06. The other end of the resistor R06 is connected to one end of the capacitor C05;
[0035] Among them, the DC input circuit 02 includes a fuse F1, a resistor R12, and a diode D1; the voltage stabilizing circuit 03 includes a three-terminal voltage regulator U2 and a voltage stabilizing diode DW, and the voltage stabilizing circuit 03 further includes a capacitor C1, a resistor R2, a capacitor C3, and a capacitor C2; the control circuit 04 includes a single-chip microcomputer U1, a capacitor C4, a capacitor C5, a resistor R14, a resistor R13, a resistor R11, a light-emitting diode D2, and a light-emitting diode D3; the DC output circuit 05 includes a PMOS transistor Q1 and an NPN transistor Q2, and the DC output circuit 05 further includes a resistor R9, a resistor R8, a resistor R10, a resistor R15, a resistor R7, a resistor R1, a resistor R3, a resistor R4, a resistor R5, a resistor R6, an interface DC-out, and a capacitor C6; the charging protection circuit further includes a programming and writing circuit, and the output terminal of the programming and writing circuit is connected to the programming terminal of the control circuit 04; the programming and writing circuit includes a "write" interface and a capacitor C7;
[0036] Among them, one end of the fuse F1 is connected to the DC-in terminal, and the other end of the fuse F1 is connected to one end of the resistor R3. One end of the resistor R12 is connected to the DC-in terminal, and the other end of the resistor R12 is connected to the positive electrode of the diode D1. The negative electrode of the diode D1 is connected to one end of the capacitor C1; one end of this capacitor C1 is connected in parallel to one end of the resistor R2 and the negative electrode of the diode D1, the other end of the capacitor C1 is grounded, the other end of the resistor R2 is connected in parallel to the "3" terminal of the three-terminal voltage regulator U2, one end of the capacitor C2 and the negative electrode of the voltage regulator DW. The other end of the capacitor C2 and the positive electrode of the voltage regulator DW are grounded together. The "1" terminal of the voltage regulator U2 is grounded, and the "2" terminal of the voltage regulator U2 is connected in parallel to one end of the capacitor C3 and the "16" terminal of the single-chip microcomputer U1; the "1" terminal of this single-chip microcomputer U1 is grounded, the "3" terminal of the single-chip microcomputer U1 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to the positive electrode of the light-emitting diode D2, and the negative electrode of the light-emitting diode D2 is grounded. The "9" terminal of the single-chip microcomputer U1 is connected in parallel to one end of the resistor R10 and one end of the resistor R11. The other end of the resistor R11 is connected to the positive electrode of the light-emitting diode D3, and the negative electrode of the light-emitting diode D3 is grounded. The "10" terminal of the single-chip microcomputer U1 is connected to one end of the resistor R14 and one end of the resistor R9. The "13" terminal of the single-chip microcomputer U1 is connected to one end of the capacitor C5 and one end of the resistor R8. The other end of the capacitor C5 is grounded. The "16" terminal of the single-chip microcomputer U1 is connected to the other end of the resistor R14 and one end of the capacitor C4, and the other end of the capacitor C4 is grounded; the "16" terminal of the single-chip microcomputer U1 is also connected to one end of the capacitor C7 and the "1" terminal of the interface write. The other end of the capacitor C7 is grounded. The "5" terminal of the single-chip microcomputer U1 is connected to the "4" terminal of the interface write. The "7" terminal of the single-chip microcomputer U1 is connected to the "3" terminal of the interface write. The "2" terminal of the interface write is grounded; the other end of this resistor R9 is connected to the "2" terminal of the interface DC-out. The other end of the resistor R8 is connected to the "1" terminal of the interface DC-out and one end of the resistor R1. The other end of the resistor R1 is grounded. The other end of the resistor R10 is connected to the base of the NPN transistor Q2. The emitter of the NPN transistor Q2 is grounded. The collector of the NPN transistor Q2 is connected to one end of the resistor R15. The other end of the resistor R15 is connected to the gate of the PMOS transistor Q1 and one end of the resistor R7. The other end of the resistor R7 is connected to one end of the resistor R3, the source of the PMOS transistor Q1, and the other end of the fuse F1. The drain of the PMOS transistor Q1 is connected to the "3" terminal of the interface DC-out. The other end of the resistor R3 is connected to one end of the resistor R4. The other end of the resistor R4 is connected to one end of the resistor R5 and one end of the resistor R6. The other end of the resistor R6 is connected to one end of the capacitor C6, and the other end of the capacitor C6 is grounded together with the other end of the resistor R5.
[0037] Specific implementation principle of the utility model: 1. Charging input indication: The interface DC_in is inserted into the charger (charging power supply). Through R12 - D1 - R2, power is supplied to U2, generating a stable 5V voltage to power the single-chip microcomputer U1. C1 - C2 filter the input power supply to make the voltage more stable. D1 emits light to indicate the power input, and DW clamps the input voltage to prevent the input voltage from exceeding the withstand voltage of U2 and causing breakdown.
[0038] 2. Judging the dedicated charger: R3 - R4 - R5 - C6 sample the input voltage and send it to the 15th pin of the single-chip microcomputer U1 for detection. If the single-chip microcomputer detects that the voltage and pulse meet the set range, a high level is output at the 9th pin of U1. Through R10, the triodes Q1 - Q2 are turned on, and at the same time, through R11, the indicator light D3 emits light to indicate that there is a charging output. The charging input voltage passes through the fuse F1 - Q1 to the charging output interface DC-out to charge the lithium battery. The pulse output from the 3rd pin of the single-chip microcomputer makes the indicator light D2 blink normally through R13. If it is detected that the charger does not meet the correct requirements, charging cannot be started, and a warning pulse is output from the 3rd pin of the single-chip microcomputer U1, making the indicator light D2 emit a warning error blink indication through R13.
[0039] 3. Detecting normal charging: A normal charging current generates a voltage signal at R1, which is sent to the 13th pin of the single-chip microcomputer U1 through R8 to judge whether the charging current is within the normal range. When the battery charging tends to be saturated, the charging current will drop below 10% of the normal current. The single-chip microcomputer makes a judgment of charging saturation, turns off the charging output, stops the high-level output at the 9th pin of U1, the indicator light D3 stops emitting light, a saturation state signal is output at the 3rd pin, and the indicator light D2 emits a saturation indication signal.
[0040] 4. Maximum charging time limit: The charger judges charging saturation based on the saturation voltage. If some of the battery cells in the battery pack are abnormal, the total charging voltage cannot reach the saturation voltage, and charging cannot enter the saturation state for a long time, resulting in overcharging of the battery pack and damaging the battery. According to the capacity of the battery pack, when the single-chip microcomputer judges that the charging time is sufficient, even if the saturation state is not detected, charging should also be stopped and a saturation indication should be given.
[0041] Although the embodiments of the present utility model have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.
Claims
1. A new charging protection circuit, characterized in that: The charging protection circuit comprises: a power supply circuit, a DC input circuit, a voltage stabilizing circuit, a control circuit and a DC output circuit, wherein the output end of the power supply circuit is connected to the input end of the DC input circuit, the output end of the DC input circuit is connected to the input end of the voltage stabilizing circuit, the output end of the voltage stabilizing circuit is connected to the input end of the control circuit, the output end of the control circuit is connected to the input end of the DC output circuit, and the output end of the DC output circuit is output to the outside; Wherein, the control circuit includes a single-chip microcomputer control chip.
2. A novel charging protection circuit according to claim 1, characterized in that: The power supply circuit includes a power input circuit, a rectifier and filter circuit, a power transformer circuit, a power control circuit and a power output circuit. The input end of the power input circuit is connected to an external AC power supply, the output end of the power input circuit is connected to the input end of the rectifier and filter circuit, the output end of the rectifier and filter circuit is connected to the input end of the power transformer circuit, the output end of the power transformer circuit is respectively connected to the input end of the power control circuit and the input end of the power output circuit, and the output end of the power output circuit is connected to the input end of the DC input circuit.
3. A novel charging protection circuit according to claim 1, characterized in that: The DC input circuit includes a fuse F1, a resistor R12 and a diode D1, one end of the fuse F1 is connected to the output end of the power supply circuit, the other end of the fuse F1 is connected to the control end of the DC output circuit, one end of the resistor R12 is connected to the output end of the power supply circuit, the other end of the resistor R12 is connected to the positive electrode of the diode D1, and the negative electrode of the diode D1 is connected to the input end of the voltage stabilizing circuit.
4. A novel charging protection circuit according to claim 1, characterized in that: The voltage stabilizing circuit includes a three-terminal voltage stabilizing tube U2 and a voltage stabilizing tube DW. The input end of the three-terminal voltage stabilizing tube U2 and the input end of the voltage stabilizing tube DW are connected to the output end of the DC input circuit. The ground end of the three-terminal voltage stabilizing tube U2 and the ground end of the voltage stabilizing tube DW are grounded. The output end of the three-terminal voltage stabilizing tube U2 is connected to the input end of the control circuit.
5. A novel charging protection circuit according to claim 4, characterized in that: The voltage stabilizing circuit also includes a capacitor C1, a resistor R2, a capacitor C3 and a capacitor C2, one end of the capacitor C1 is connected in parallel to one end of the resistor R2 and the output end of the DC input circuit, the other end of the capacitor C1 is grounded, the other end of the resistor R2 is connected in parallel to the input end of the three-terminal voltage regulator U2, one end of the capacitor C2 and the negative electrode of the voltage regulator DW, the other end of the capacitor C2 and the positive electrode of the voltage regulator DW are grounded, the ground end of the voltage regulator U2 is grounded, the output end of the voltage regulator U2 is connected in parallel to one end of the capacitor C3 and the input end of the control circuit, and the other end of the capacitor C3 is grounded.
6. A novel charging protection circuit according to claim 1, characterized in that: The control circuit includes a single-chip computer U1, a capacitor C4, a capacitor C5, a resistor R14, a resistor R13, a resistor R11, a light-emitting diode D2 and a light-emitting diode D3. The "1" terminal of the single-chip computer U1 is grounded, the "3" terminal of the single-chip computer U1 is connected to one end of the resistor R13, the other end of the resistor R13 is connected to the positive electrode of the light-emitting diode D2, and the negative electrode of the light-emitting diode D2 is grounded. The "9" terminal of the single-chip computer U1 is connected in parallel to one end of the input end of the DC output circuit and one end of the resistor R11, the other end of the resistor R11 is connected to the positive electrode of the light-emitting diode D3, and the negative electrode of the light-emitting diode D3 is grounded. The "10" terminal of the single-chip computer U1 is connected to one end of the resistor R14 and two ends of the input end of the DC output circuit. The "13" terminal of the single-chip computer U1 is connected to one end of the capacitor C5 and three ends of the input end of the DC output circuit, the other end of the capacitor C5 is grounded, and the "16" terminal of the single-chip computer U1 is connected to the other end of the resistor R14 and one end of the capacitor C4, and the other end of the capacitor C4 is grounded.
7. A novel charging protection circuit according to claim 1, characterized in that: The DC output circuit includes a PMOS tube Q1 and an NPN tube Q2, the base of the NPN tube Q2 is connected to the output end of the control circuit, the emitter of the NPN tube Q2 is grounded, the collector of the NPN tube Q2 is connected to the gate of the PMOS tube Q1, the drain of the PMOS tube Q1 serves as the output end, and the source of the PMOS tube Q1 is connected to the output end of the DC input circuit.
8. A novel charging protection circuit according to claim 7, characterized in that: The DC output circuit also includes a resistor R9, a resistor R8, a resistor R10, a resistor R15, a resistor R7, a resistor R1, a resistor R3, a resistor R4, a resistor R5, a resistor R6, an interface DC-out and a capacitor C6, one end of the resistor R9, one end of the resistor R8 and one end of the resistor R10 are respectively connected to the output end of the control circuit, the other end of the resistor R9 is connected to the interface DC-out "2" terminal, the other end of the resistor R8 is connected to the interface DC-out "1" terminal and one end of the resistor R1, the other end of the resistor R1 is grounded, and the other end of the resistor R10 is connected to the base of the NPN tube Q2 The emitter of the NPN tube Q2 is grounded, the collector of the NPN tube Q2 is connected to one end of a resistor R15, the other end of the resistor R15 is connected to the gate of the PMOS tube Q1 and one end of a resistor R7, the other end of the resistor R7 is connected to one end of a resistor R3, the source of the PMOS tube Q1 and the output end of the DC input circuit, the drain of the PMOS tube Q1 is connected to the DC-out "3" terminal of the interface, the other end of the resistor R3 is connected to one end of a resistor R4, the other end of the resistor R4 is connected to one end of a resistor R5 and one end of a resistor R6, the other end of the resistor R6 is connected to one end of a capacitor C6, and the other end of the capacitor C6 and the other end of the resistor R5 are grounded together.
9. A novel charging protection circuit according to claim 2, characterized in that: The power input circuit includes a fuse F01, a capacitor CX01, a mutual inductance T01 and a capacitor CX02, one end of the fuse F01 is connected to the live wire of the alternating current, the other end of the fuse F01 is connected in parallel to one end of the capacitor CX01 and one end of the input end of the mutual inductance T01, the other end of the capacitor CX01 and the other end of the input end of the mutual inductance T01 are connected to the neutral wire of the alternating current, one end of the output end of the mutual inductance T01 is connected in parallel to one end of the input end of the rectifier and filter circuit and one end of the capacitor CX02, and the other end of the output end of the mutual inductance T01 is connected in parallel to the other end of the input end of the rectifier and filter circuit and the other end of the capacitor CX02.
10. A novel charging protection circuit according to claim 2, characterized in that: The rectifier and filter circuit includes a rectifier bridge BD1, an inductor L1, a resistor R02, a capacitor C01, a capacitor C02, an inductor L2, a resistor R03, a resistor R04, a capacitor C06 and a diode D03. One end of the output end of the power input circuit is connected to one end of the input end of the rectifier bridge BD1, and the other end of the output end of the power input circuit is connected to the other end of the input end of the rectifier bridge BD1. One end of the output end of the rectifier bridge BD1 is connected in parallel to one end of the inductor L1, one end of the resistor R02 and one end of the capacitor C01. The other end of the output end of the rectifier bridge BD1 is connected in parallel to One end of the inductor L2 and the other end of the capacitor C01, the other end of the inductor L2 is connected in parallel to one end of the capacitor C02 and one end of the power control circuit, the other end of the capacitor C02 is connected in parallel to the other end of the inductor L1, the other end of the resistor R02, one end of the resistor R03, one end of the capacitor C06 and one end of the input end of the power transformer circuit, the other end of the resistor R03 is connected to the other end of the capacitor C06 and one end of the resistor R04, the other end of the resistor R04 is connected to the cathode of the diode D03, and the anode of the diode D03 is connected to the other end of the input end of the power transformer circuit.