CN209994132U

CN209994132U - Charging alarm control circuit for digital product

Info

Publication number: CN209994132U
Application number: CN201920824531.0U
Authority: CN
Inventors: 范海峰; 陈桃根
Original assignee: Shenzhen Dfs Technology Co Ltd
Current assignee: Shenzhen Dfs Technology Co Ltd
Priority date: 2019-06-03
Filing date: 2019-06-03
Publication date: 2020-01-24
Anticipated expiration: 2029-06-03

Abstract

The utility model discloses a digital product alarm control circuit that charges, little the control unit receives or provides radio signal through wireless module, little the control unit carries out bee calling organ SP 1's warning through control bee calling organ drive circuit, little the control unit receives the voltage signal that external power supply feedback was come and the temperature signal of external equipment head department that charges through external temperature detection circuit and external temperature detection circuit, little the control unit carries out the detection and the control charge of electric current and feeds back its control signal to little the control unit to the output port through current detection and control circuit, power management IC circuit makes its control external power supply circuit to little the control unit and output port power supply through cooperating with little the control unit, belong to the alarm control circuit technical field that charges, the utility model discloses have the function to the head that charges overcurrent and excessive temperature protection.

Description

Charging alarm control circuit for digital product

Technical Field

The invention relates to a charging alarm control circuit, in particular to a charging alarm control circuit for a digital product, and belongs to the technical field of charging alarm control circuits.

Background

The charger adopts a high-frequency power supply technology, applies an advanced intelligent dynamic adjustment charging technology, the power frequency machine is designed by the traditional analog circuit principle, the internal electric devices (such as a transformer, an inductor, a capacitor and the like) of the machine are large, and small noise exists in the general operation with large load, but the machine type has stronger resistance performance in severe power grid environment conditions, and the reliability and the stability are stronger than those of the high-frequency machine.

Nowadays, the protection of the charger is very little, and the problem of spontaneous combustion of the digital product due to damage caused by overheating and overvoltage in the charging process of the digital product often exists, so that a circuit for performing charging alarm control on the digital product is needed, and the protection effect in the charging process of the digital product is realized.

Disclosure of Invention

The invention mainly aims to provide a charging alarm control circuit of a digital product, which has the function of overcurrent, overvoltage and overtemperature protection on a charging head.

The purpose of the invention can be achieved by adopting the following technical scheme:

the utility model provides a digital product alarm control circuit that charges, includes little the control unit, bee calling organ drive circuit, wireless module, external power supply voltage detection circuitry, external temperature detection circuitry, power management IC circuit, external power supply circuit, current detection and control circuit and output port, its characterized in that, little the control unit: the system is used for charging control, defense control, alarm control and state display;

buzzer drive circuit: when an alarm occurs, the buzzer is driven to give out a sharp alarm sound to play a role in driving the buzzer to alarm and remind;

a wireless module: the function of wireless receiving is achieved;

external power supply voltage detection circuit: the micro-control unit is used for detecting the external voltage, and cutting off the external charging circuit under the control of the micro-control unit when the external voltage is too high;

the external temperature detection circuit: the micro control unit is used for detecting the temperature of the charging head of the external equipment during charging, and cutting off the current of the port through the micro control unit when the temperature of the charging head of the external equipment is overhigh;

power management IC circuit: the micro-control unit is used for controlling the electric quantity flow and the flow direction output by the external power supply circuit to match the control requirement of the micro-control unit;

an external power supply circuit: a voltage for supplying the micro control unit with a stable voltage;

the current detection and control circuit: the current detection and charging control function is achieved when the first output port is used for charging;

the micro control unit receives or sends a wireless signal through the wireless module, the micro control unit gives an alarm through controlling the buzzer driving circuit to carry out buzzer SP1, the micro control unit receives a voltage signal fed back by an external power supply and a temperature signal at a charging head of an external device through an external temperature detection circuit and an external temperature detection circuit, the micro control unit carries out current detection and control charging on an output port through a current detection and control circuit and feeds back a control signal to the micro control unit, and the power management IC circuit controls the external power supply circuit to supply power to the micro control unit and the output port through matching with the micro control unit.

Preferably, in the MICRO-control unit, P1.0, P1.1, P1.2, P1.3, P1.4 and P1.5 are all set as ADC interface terminals, P1.0, P1.1 and P1.2 are respectively connected with AD1 interface terminal in the first current detection and control circuit, AD2 interface terminal in the second current detection and control circuit and AD3 interface terminal in the third current detection and control circuit, P1.3 is connected with a Detector-DC interface terminal in the external power supply voltage detection circuit, P1.4 is connected with cathode of light emitting diode D1 through a wire, anode of light emitting diode D1 is connected with one end of resistor R17 through a wire, the other end of resistor R17 is connected with power supply VCC through a wire, P1.5 is connected with one end of resistor R9 in the buzzer drive circuit through a wire, P1.6 and P1.7 in the MICRO-control unit are all set as XTAL terminals, P1.6 is connected with ro interface terminals of the first current detection and ro interface circuit, USB interface 3 and USB interface 3, wherein USB interface 3 and USB interface terminal 368 are connected with USB interface terminal, p1.7 is connected with PT2 terminal of MICROUSB in the second current detection and control circuit, wherein 6, 7, 8 and 9 terminals of MICROUSB are connected, P5.4 in the MICRO-control unit is set as RST interface terminal, and P5.4 is connected with RED2 terminal in the port LED display circuit, P5.5 interface terminal in the MICRO-control unit is connected with BLUE2 terminal in the port LED display circuit, P3.2 and P3.3 in the MICRO-control unit are both set as INT interface terminal, P3.2 is connected with RED1 terminal in the port LED display circuit, P3.3 is connected with BLUE1 in the port LED display circuit, VCC interface terminal in the MICRO-control unit is connected in parallel with resistor R5 and capacitor C7 by wire, the other end ground resistor R5 of the other end of capacitor C7 is connected with power supply VCC, P3 end in the MICRO-control unit is grounded, P3.0 in the MICRO-control unit is set as RXD terminal P3.1 and is set as software terminal P3.26, and P3.26 is connected with GND interface 2 in the download interface port, p3.1 is connected with 4 interfaces in a software download port JP2 and a resistor R12, the other end of the resistor R12 is connected with a 3 interface of a linkage switch SW1, a 4 interface of the linkage switch SW and one end of a resistor R14, the other end of the resistor R14 is connected with a power supply VCC, an interface 1 of the linkage switch SW1 is connected with an interface 2 of the linkage switch SW in parallel and grounded, an interface 1 in the software download port JP2 is connected with the power supply VCC, an interface 2 in the software download port JP2 is grounded, P2.2 and P2.3 in the micro control unit are respectively connected with an interface S1CONB and an interface S1 CONA in a first current detection and control circuit, P2.4 and P2.5 in the micro control unit are respectively connected with an interface S2 CONB and an interface S2CONA in a second current detection and control circuit, P2.6 and P2.7 in the micro control unit are respectively connected with an interface S3 CONB and an interface S3A in a third current detection and control circuit, and CONA interfaces P2.1, P2.7, P3.3.3 and CE 3.3 are respectively connected with an interface 3 in a wireless interface 3 in a third current, The 4-port CS, the 5-port SCK, the 6-port MOSI, the 7-port MISO and the 8-port IRQ are connected, a group of resistor R4 and capacitor C6 are connected in parallel with the 1-port in the wireless module XN1, the other end of the resistor R4 is connected with a power supply VCC, and the other end of the capacitor C6 is connected with the wireless module XN1 to be grounded.

Preferably, the port LED display circuit includes a first port LED display circuit in which RED1 connected to P3.2 in the MICRO control unit is connected in series with a resistor R31, and the other end of the resistor R31 is connected to the base 1 of a transistor Q8, the emitter 2 of the transistor Q8 is grounded, the collector 3 of the transistor Q8 is connected to the cathode of a diode D8, the anode of the diode D8 is connected to a resistor R22, the other end of the resistor R22 is set to an LED R1 terminal and connected to the 3 terminal of the MICRO USB in the first current detection and control circuit, the BLUE2 connected to P3.3 in the MICRO control unit in the port LED display circuit is connected in series with a resistor R34, the other end of the resistor R34 is connected to the base 1 of a transistor Q10, the emitter 2 of the transistor Q8 is grounded, the collector 3 of the transistor Q6 is connected in series with a resistor R23, the other end of the LED R23 is set to a B1 and connected to the MICRO USB 7372 in the first current detection and control circuit, the RED2 connected with the P5.4 in the MICRO control unit in the second port LED display circuit is connected with a resistor R32 in series, the other end of the resistor R32 is connected with a base 1 of a triode Q9, an emitter 2 of the triode Q9 is grounded, a collector 3 of a triode Q9 is connected with a cathode of a diode D9, an anode of the diode D9 is connected with a resistor R33, the other end of the resistor R33 is set as an LED R2 end and connected with a 3 terminal of MICROUSB in the second current detection and control circuit, BLUE2 connected with the P5.5 in the MICRO control unit in the port LED display circuit is connected with a resistor R35 in series, the other end of the resistor R35 is connected with a base 1 of the triode Q11, an emitter 2 of the triode Q11 is grounded, a collector 3 of the triode Q11 is connected with a resistor R36 in series, and the other end of the resistor R36 is set as an LED B2 and connected with a terminal 2 of.

Preferably, the other end of a resistor R9 connected with P1.5 in the micro control unit in the buzzer driving circuit is connected with a base 1 of a triode Q2, an emitter 2 of the triode Q2 is grounded, a collector 3 of the triode Q2 is connected with a terminal 2 of a buzzer SP1, a terminal 2 of a T1 and one end of a capacitor C10, the terminal 1 of the buzzer is connected with a capacitor C11 in series, the other end of the C11 is grounded, a terminal 3 of the T1 is connected with the terminal 1 of the buzzer, the terminal 1 of the T1 is connected with VBAT through a conducting wire, and the other end of the capacitor C10 is grounded.

Preferably, the current detecting and controlling circuit includes a first current detecting and controlling circuit and a second current detecting and controlling circuit, one end of S1 CONA connected with P2.3 in the MICRO control unit in the first current detecting and controlling circuit is connected in series with a resistor R15, the other end of the resistor R15 is connected with the gate of a field effect transistor Q1, the source of the field effect transistor Q1 is connected with the anode of a diode D5, a capacitor C12 and a resistor R16, the cathode of the diode D5 and the other end of a capacitor C12 are connected with one end of a resistor R18 and grounded, the drain of the field effect transistor Q1, the other end of the resistor R16 and one end of a transient voltage suppression diode TVS1 are connected with the 5 terminal of micob in the first current detecting and controlling circuit, the other end of the transient voltage suppression diode TVS1 is grounded, and the 5 terminal of the micob in the first current detecting and controlling circuit is connected with the drain of a field effect transistor Q3, a source of the field effect transistor Q3 is connected to the other end of the resistor R18 and a drain of the field effect transistor Q4, a gate of the field effect transistor Q3 is connected to one end of the resistor R20, a source of the field effect transistor Q4 is connected to one end of the resistor R38 at a point P1, a gate of the field effect transistor Q4 is connected to one end of the resistor R21, the other end of the resistor R21 is connected to the other end of the resistor R20 at a point S1CONB connected to P2.3 in the MICRO control unit, the other end of the resistor R38 is connected to the capacitor C15, the other end of the capacitor C15 is grounded, a connection point of the resistor R38 and the capacitor C15 is AD1 connected to P1.0 in the MICRO control unit, a 1 connection port of the first current detection and control circuit outputs a direct current of 5V, one end of the S2CONA connected to P2.5 in the MICRO control unit in the second current detection and control circuit is connected in series to one end of the resistor R6342 and the gate of the transistor Q5. The source of the field effect transistor Q5 is connected with anode of diode D7, capacitor C14 and resistor R27, the cathode of diode D7 and another end of capacitor C14 are connected with one end of resistor R28 and grounded, the drain of the diode Q5, another end of resistor R27 and one end of transient voltage suppression diode TVS2 are all connected with 5 terminal of MICROUSB in the second current detection and control circuit, another end of transient voltage suppression diode TVS2 is grounded, and 5 terminal of MICROUSB in the second current detection and control circuit is connected with drain of field effect transistor Q6, the source of field effect transistor Q6 is connected with another end of resistor R28 and drain of field effect transistor Q7, the gate of field effect transistor Q6 is connected with one end of resistor R29, the source of field effect transistor Q7 is connected with one end of resistor R37, and the connection point is P2, the gate of field effect transistor Q7 is connected with one end of resistor R30, the other end of the resistor R30 is connected with the other end of the resistor R29, the connection point is S2 CONB and P2.4 in the MICRO control unit, the other end of the resistor R37 is connected with a capacitor C16, the other end of the capacitor C16 is grounded, the connection point of the resistor R37 and the capacitor C16 is AD2 and is connected with P1.1 in the MICRO control unit, and the 1 connection port of MICRO USB in the second current detection and control circuit outputs 5V direct current voltage.

Preferably, the external temperature detection circuit comprises a first port temperature detection circuit and a second port temperature detection circuit, a PT1 connection point in the first port temperature detection circuit is connected with P1.6 in the MICRO control unit and is connected with a capacitor C8, a resistor R10, a thermistor PT1 and a resistor R13, the other ends of the resistors R13, C8 and R10 are connected with each other and grounded, the other end of the thermistor PT1 is connected with an upper resistor R7 through a connection point, the other end of the upper resistor R7 is connected with a power supply, a PT1A connection point is arranged at the connection point of the thermistor PT1 and the upper resistor R7, the PT1A connection point is connected with the 4 port of the MICRO USB in the first current detection and control circuit, a PT2 connection point in the second port temperature detection circuit is connected with P1.7 in the MICRO control unit and is connected with a capacitor C13, a resistor R24, a resistor PT2 and a resistor R25, the other end of the resistor R25, the capacitor C13 and the PT 24 are connected with each, the other end of the thermistor PT2 is connected with an upper resistor R11, the other end of the upper resistor R11 is connected with a power supply, a PT2A connection point is arranged at the connection position of the thermistor PT2 and the upper resistor R11, and the PT2A connection point is connected with a 4 connection port of a MICROUSB in the second current detection and control circuit.

Preferably, the other end of the Detector-DC connected to P1.3 in the mcu is connected to a resistor R6 and a resistor R8, the other end of the resistor R8 is grounded, the other end of the resistor R6 is connected to one end of a resistor R3, the other end of the resistor R3 outputs voltage, the other end of the resistor R3 is connected to the positive electrodes of a capacitor C5 and a polar capacitor C4, the other end of the capacitor C5 is grounded, and the negative electrode of the polar capacitor C4 is grounded.

Preferably, the power management IC circuit includes a charging management IC chip U2, a digital interface VIN end of the charging management IC chip U2 is connected to a positive electrode of the polar capacitor C4, a pin PROG of the charging management IC chip U2 is connected to one end of the resistor R2, the other end of the resistor R2 is grounded, a voltage output end VOUT of the charging management IC chip U2 is connected to an interface 1 of the battery BAT, a digital ground VSS of the charging management IC chip U2 is grounded, the voltage output end VOUT of the charging management IC chip U2 is further connected to the capacitor C3, the other end of the capacitor C3 is grounded, a terminal 2 of the battery BAT is grounded, and a BAT point is located at an interface 1 of the battery BAT and the voltage output end VOUT of the charging management IC chip U2.

Preferably, the external power circuit comprises a power circuit and an auxiliary power circuit, the power circuit comprises a charge management IC chip U1, an input terminal IN of the charge management IC chip U1 is connected with a capacitor C2, a positive electrode of a polar capacitor C9, a cathode of a diode D6 and a cathode of a diode D4, the other end of the capacitor C2 is connected with a negative electrode of the polar capacitor C9 and grounded, an anode of a diode D6 outputs voltage, an anode of a diode D4 is connected with a voltage output terminal VOUT of the charge management IC chip U2 and a 1-interface BAT IN the battery BAT, a ground terminal GND of the charge management IC chip U1 is connected with ground, an output terminal OUT of the charge management IC chip U1 is connected with a capacitor C1 and a power VCC, the other end of the capacitor C1 is grounded, a resistor R1 is connected IN the auxiliary power circuit through a point at the 1-interface BAT with the voltage output terminal VOUT of the charge management IC chip U2, the other end of the resistor R1 is connected with an anode 686, the cathode of the diode D2 outputs a voltage.

The invention has the beneficial technical effects that:

1. overvoltage protection: r3, R6, R8 in the circuit constitute voltage sampling circuit, and MCU is sent to the sampled voltage, and when external voltage was too high (surpassed preset voltage), through MCU's control, Q1, Q3, Q4 cut off, cut off external charging current, played the overvoltage protection effect.

2. Overcurrent protection: after the protection is started, after Q1, Q3 and Q4 are all turned on, the level detected by the P1 end is the voltage of R18 (the resistance is small, the internal resistance of the MOS transistor is small, so the voltage is small), when the charging current is large (or the load is short-circuited), the voltage on R18 is further increased, and when the charging current exceeds a preset value, the MCU controls Q1, Q3 and Q4 to be turned off (S1_ CONA and S1_ CONB are low), and the charging loop at this time: and the charging current of the pin 5-R16 of the +5V load port and D5 is very small, so that the overcurrent protection effect is achieved, and when the overcurrent occurs, the voltage detected by the ADC is the voltage of the D5 end.

3. And (3) over-temperature protection: r7, PT1 (thermistor, this resistance welding is on external charging head, is used for surveying the temperature of external charging head and external device junction) C8 in the circuit, R10 constitutes voltage sampling circuit, when detecting voltage and surpassing preset voltage (the temperature of charging head and equipment junction is too high), through MCU's control, cuts external device's charging current, plays the excess temperature protection. The function is mainly considered that the charging current is not very large, but the temperature of the connection part of the charging head and the external equipment is too high due to other reasons, so that the charging head or the external equipment is burnt out.

Drawings

FIG. 1 is a system diagram of a preferred embodiment of a digital product charging alarm control circuit according to the present invention;

FIG. 2 is a circuit diagram of the micro control unit and the bottom switch of the alarm according to a preferred embodiment of the charging alarm control circuit of the digital product of the present invention;

fig. 3 is a circuit diagram of a wireless module of a preferred embodiment of a digital product charging alarm control circuit according to the present invention;

FIG. 4 is a circuit diagram of a software download port of a preferred embodiment of the digital product charging alarm control circuit according to the present invention;

FIG. 5 is a circuit diagram of a port LED display of a preferred embodiment of a digital product charging alarm control circuit according to the present invention;

fig. 6 is a buzzer driving circuit diagram of a preferred embodiment of the digital product charging alarm control circuit according to the present invention;

fig. 7 is a first current detection and control circuit diagram of a preferred embodiment of a digital product charging alarm control circuit according to the present invention;

fig. 8 is a second current sensing and control circuit diagram of a preferred embodiment of a digital product charging alarm control circuit in accordance with the present invention;

fig. 9 is a diagram of a first external temperature detection circuit of a preferred embodiment of the digital product charging alarm control circuit according to the present invention;

fig. 10 is a second external temperature detection circuit diagram of a preferred embodiment of the digital product charging alarm control circuit according to the present invention;

fig. 11 is a circuit diagram of an external power voltage detection circuit of a preferred embodiment of the digital product charging alarm control circuit according to the present invention;

FIG. 12 is a power management IC circuit diagram of a preferred embodiment of a digital product charging alarm control circuit according to the present invention;

fig. 13 is a circuit diagram of an external power supply of a preferred embodiment of the charging alarm control circuit of the digital product according to the present invention.

Detailed Description

In order to make the technical solutions of the present invention more clear and definite for those skilled in the art, the present invention is further described in detail below with reference to the examples and the accompanying drawings, but the embodiments of the present invention are not limited thereto.

In this embodiment, as shown in fig. 1, the charging alarm control circuit for digital products provided in this embodiment includes a micro control unit, a buzzer driving circuit, a wireless module, an external power voltage detection circuit, an external temperature detection circuit, a power management IC circuit, an external power circuit, a current detection and control circuit and an output port, where the micro control unit receives or issues a wireless signal through the wireless module, the micro control unit controls the buzzer driving circuit to alarm the buzzer SP1, the micro control unit receives a voltage signal fed back from the external power and a temperature signal at a charging head of an external device through the external temperature detection circuit and the external temperature detection circuit, the micro control unit detects and controls the charging of the output port through the current detection and control circuit and feeds back a control signal to the micro control unit, the power management IC circuit is matched with the micro control unit to control the external power supply circuit to supply power to the micro control unit and the output port.

In this embodiment, as shown in fig. 2, 3 and 4, P1.0, P1.1, P1.2, P1.3, P1.4 and P1.5 in the MICRO control unit are all set as ADC interface terminals, P1.0, P1.1 and P1.2 are respectively connected with AD1 interface terminal in the first current detection and control circuit, AD2 interface terminal in the second current detection and control circuit and AD3 interface terminal in the third current detection and control circuit, P1.3 is connected with a Detector-DC interface terminal in the external power supply voltage detection circuit, P1.4 is connected with the cathode of the light emitting diode D1 through a wire, the anode of the light emitting diode D1 is connected with one end of the resistor R17 through a wire, the other end of the resistor R17 is connected with the power supply VCC through a wire, P1.5 is connected with one end of the resistor R9 in the buzzer driving circuit through a wire, P1.6 and P1.7 in the MICRO control unit are all set as XTAL terminal, P1.6 and P1.5 are connected with the first current detection circuit and the USB interface terminal 1, wherein the 6, 7, 8 and 9 terminals of MICROUSB are terminated, P1.7 is connected with PT2 terminal of MICROUSB in the second current detection and control circuit, wherein the 6, 7, 8 and 9 terminals of MICROUSB are terminated, P5.4 in the MICRO control unit is RST interface terminal, P5.4 is connected with RED2 terminal in the port LED display circuit, P5.5 interface terminal in the MICRO control unit is connected with BLUE2 terminal in the port LED display circuit, P3.2 and P3.3 in the MICRO control unit are INT interface terminals, P3.2 is connected with RED1 terminal in the port LED display circuit, P3.3 is connected with BLUE1 terminal in the port LED display circuit, VCC interface terminal in the MICRO control unit is connected with resistor R5 and capacitor C7 in parallel by wires, the other end of resistor R5 of capacitor C7 is connected with power supply, VCC terminal in the MICRO control unit is grounded, P3.0 is RXD interface terminal in the MICRO control unit is GND 3.3 terminal, GND interface terminal is GND 3.3 terminal in the MICRO control unit is GND 3 terminal connected with GND 3 terminal, p3.0 is connected with interface 3 in software download port JP2, P3.1 is connected with interface 4 in software download port JP2 and resistor R12, the other end of resistor R12 is connected with interface 3 of ganged switch SW1, interface 4 of ganged switch SW and one end of resistor R14, the other end of resistor R14 is connected with power VCC, interface 1 of ganged switch SW1 is connected with interface 2 of ganged switch SW in parallel and grounded, interface 1 in software download port JP2 is connected with power VCC, interface 2 in software download port JP2 is grounded, P2.2 and P2.3 in the micro control unit are respectively connected with interfaces S1CONB and S1 CONA in the first current detection and control circuit, P2.4 and P2.5 in the micro control unit are respectively connected with interfaces S2 CONB and S2CONA in the second current detection and control circuit, P2.6 and P2.7 in the micro control unit are respectively connected with interfaces S3 and S3 in the third current detection and control circuit, and CONB 2 are respectively connected with interface 1.2 in the micro control unit, P2.0, P3.7, P3.6, P3.5 and P3.4 are respectively connected with 3 ports CE, 4 ports CS, 5 ports SCK, 6 ports MOSI, 7 ports MISO and 8 ports IRQ in a wireless module XN1, a group of resistor R4 and capacitor C6 are connected in parallel with a port 1 in a wireless module XN1, the other end of the resistor R4 is connected with a power supply VCC, and the other end of the capacitor C6 is connected with the wireless module XN1 to be grounded.

The charging control, the defense deployment control, the alarm control and the state display are realized through the micro control unit, the wireless receiving and sending of the digital code of the micro control unit are realized through the wireless module XN1, the software download port JP2 is used for carrying out online downloading programs, the other end of the resistor R12 is connected with the 3 interface of the linked switch SW1, the 4 interface of the linked switch SW and one end of the resistor R14, the other end of the resistor R14 is connected with the power VCC, the 1 interface of the linked switch SW1 and the 2 interface of the linked switch SW are connected in parallel to form an alarm bottom switch, when the alarm is in an anti-theft state, when the alarm is prized up, the alarm is generated, and the anti-theft device and the external equipment are taken away together artificially.

The micro control unit related to the method adopts a single chip microcomputer of LAP5W413AS model, and the single chip microcomputer of LAP5W413AS model has circuits such as a central processing unit CPU with good digital processing capacity, a random access memory RAM, a read only memory ROM, various I/O ports and interrupt systems, a timer/counter and other functional display driving circuits, a pulse width modulation circuit, an analog multiplexer, an A/D converter and the like.

In the present embodiment, as shown in fig. 5, the port LED display circuit includes a first port LED display circuit and a second port LED display circuit, a resistor R31 is connected in series with RED1 connected to P3.2 in the MICRO control unit in the first port LED display circuit, and the other end of the resistor R31 is connected to the base 1 of a transistor Q8, the emitter 2 of the transistor Q8 is grounded, the collector 3 of the transistor Q8 is connected to the cathode of a diode D8, the anode of the diode D8 is connected to a resistor R22, the other end of the resistor R22 is connected to the terminal of a LED R1 and to the terminal 3 of a MICRO USB in the first current detection and control circuit, a resistor R34 is connected in series with BLUE1 connected to P3.3 in the MICRO control unit in the port LED display circuit, the other end of the resistor R34 is connected to the base 1 of the transistor Q10, the emitter 2 of the transistor Q10 is grounded, the collector 3 of the transistor Q10 is connected to the terminal R23 in series, the other end of the resistor R23 is connected to the MICRO USB terminal 1 and to the first current detection, the RED2 connected with the P5.4 in the MICRO control unit in the second port LED display circuit is connected with a resistor R32 in series, the other end of the resistor R32 is connected with the base 1 of a triode Q9, the emitter 2 of the triode Q9 is grounded, the collector 3 of a triode Q9 is connected with the cathode of a diode D9, the anode of the diode D9 is connected with a resistor R33, the other end of the resistor R33 is set as the end of the LED R2 and connected with the 3 terminal of the MICROUSB in the second current detection and control circuit, the BLUE2 connected with the P5.5 in the MICRO control unit in the port LED display circuit is connected with a resistor R35 in series, the other end of the resistor R35 is connected with the base 1 of the triode Q11, the emitter 2 of the triode Q11 is grounded, the collector 3 of the triode Q11 is connected with the resistor R36 in series, the other end of the resistor R36 is set as the end of the LED B2 and, the port LED display circuit is used for displaying whether the external equipment is connected or not or giving an alarm.

The diodes involved in the method are all in the type of 1N5819, are Schottky diodes, have reverse withstand voltage of 40V, have extremely short reverse recovery time of rated forward current 1A and 1N5819, are suitable for high-frequency circuit work, are all in the type of BC847, are patch-shaped, occupy small space and are suitable for integrated circuits.

In the embodiment, as shown in fig. 6, the other end of a resistor R9 connected with P1.5 in the micro control unit in the buzzer driving circuit is connected with a base 1 of a triode Q2, an emitter 2 of the triode Q2 is grounded, a collector 3 of the triode Q2 is connected with a terminal 2 of a buzzer SP1, a terminal 2 of a capacitor T1 and one end of a capacitor C10, the terminal 1 of the buzzer is connected in series with a capacitor C11, the other end of the capacitor C11 is grounded, a terminal 3 of the capacitor T1 is connected with the terminal 1 of the buzzer, the terminal 1 of the capacitor T1 is connected with VBAT through a conducting wire, the other end of the capacitor C10 is grounded, and when an alarm occurs, the buzzer SP1 gives a sharp alarm sound to play a role in reminding.

Reference herein is made to a T1 model number L200 and a buzzer SP1 model number TMB12a 05.

In the present embodiment, as shown in fig. 7 and 8, the current detecting and controlling circuit includes a first current detecting and controlling circuit and a second current detecting and controlling circuit, one end of S1 CONA connected to P2.3 in the MICRO control unit in the first current detecting and controlling circuit is connected in series with a resistor R15, the other end of the resistor R15 is connected to the gate of a field effect transistor Q1, the source of the field effect transistor Q1 is connected to the anode of a diode D5, a capacitor C12 and a resistor R16, the cathode of the diode D5 and the other end of a capacitor C12 are connected to one end of a resistor R18 and grounded, the drain of the field effect transistor Q1, the other end of the resistor R16 and one end of a transient voltage suppressing diode TVS1 are connected to the 5 terminal of micousb in the first current detecting and controlling circuit, the other end of the transient voltage suppressing diode TVS1 is grounded, and the 5 terminal of the micousb is connected to the drain of the field effect transistor Q3 in the first current detecting and controlling circuit, a source of a field effect transistor Q3 is connected to the other end of a resistor R18 and a drain of a field effect transistor Q4, a gate of a field effect transistor Q3 is connected to one end of a resistor R20, a source of a field effect transistor Q4 is connected to one end of a resistor R38 at a point P1, a gate of a field effect transistor Q4 is connected to one end of a resistor R21, the other end of a resistor R21 is connected to the other end of a resistor R20 at a point S1CONB connected to P2.3 in the MICRO control unit, the other end of a resistor R38 is connected to a capacitor C15, the other end of the capacitor C15 is grounded, a point AD1 connected to the resistor R15 is connected to P1.0 in the MICRO control unit, a 1 connection port of MICROUSB in the first current detection and control circuit outputs a DC voltage of 5V, one end of S2CONA connected to P2.5 in the MICRO control unit in the second current detection and control circuit is connected in series to a resistor R26, the other end of the resistor R26 is connected with the gate of the field effect transistor Q5, the source of the field effect transistor Q5 is connected with the anode of the diode D7, the capacitor C14 and the resistor R27, the cathode of the diode D7 and the other end of the capacitor C14 are connected with one end of the resistor R28 and are grounded, the drain of the field effect transistor Q5, the other end of the resistor R27 and one end of the transient voltage suppression diode TVS2 are all connected with the 5 terminal of MICROUSB in the second current detection and control circuit, the other end of the transient voltage suppression diode TVS2 is grounded, the 5 terminal of MICROUSB in the second current detection and control circuit is connected with the drain of the field effect transistor Q6, the source of the field effect transistor Q6 is connected with the other end of the resistor R28 and the drain of the field effect transistor Q7, the gate of the field effect transistor Q6 is connected with one end of the resistor R29, the source of the field effect transistor Q7, the connection point is a point P2, the gate of a field effect transistor Q7 is connected with one end of a resistor R30, the other end of the resistor R30 is connected with the other end of a resistor R29, the connection point is S2 CONB and is connected with P2.4 in the MICRO control unit, the other end of the resistor R37 is connected with a capacitor C16, the other end of the capacitor C16 is grounded, the connection point of the resistor R37 and the capacitor C16 is AD2 and is connected with P1.1 in the MICRO control unit, and a 1 connection port of a MICRO USB in the second current detection and control circuit outputs 5V direct current voltage to play a role in current detection and charging control.

The field effect transistor related to the field effect transistor adopts a SI2312 model, the field effect transistor is a patch-shaped field effect transistor, the occupied space is small, and the field effect transistor is suitable for an integrated circuit, and the transient voltage suppression diode TVS adopts an ESD05 model.

In this embodiment, as shown in fig. 9 and 10, the external temperature detection circuit includes a first port temperature detection circuit and a second port temperature detection circuit, a PT1 connection point in the first port temperature detection circuit is connected to P1.6 in the MICRO control unit and is connected to a capacitor C8, a resistor R10, a thermistor PT1 and a resistor R13, the other ends of the resistor R13, the capacitor C8 and the resistor R10 are connected to each other and grounded, the other end of the thermistor PT1 is connected to an upper resistor R7, the other end of the upper resistor R7 is connected to a power supply, a PT1A connection point is provided at a connection point where the thermistor PT1 and the upper resistor R7 are connected, the PT1A connection point is connected to a 4 connection port of the USB in the first current detection and control circuit, a PT2 connection point in the second port temperature detection circuit is connected to P1.7 in the MICRO control unit and is connected to a capacitor C13, a resistor R24, a thermistor 2 and a resistor 25, a resistor 25, a capacitor C13 and a resistor 24 are connected to each other end of each, the other end of the thermistor PT2 is connected with an upper resistor R11, the other end of the upper resistor R11 is connected with a power supply, a connecting position of the thermistor PT2 and the upper resistor R11 is set as a PT2A wiring point, the PT2A wiring point is connected with a 4 wiring port of a MICRO USB in the second current detection and control circuit, and when the temperature at the charging head of the external equipment is out of date, the current of the port is disconnected through the MICRO control unit.

In this embodiment, as shown in fig. 11, the other end of the Detector-DC connected to P1.3 in the mcu is connected to a resistor R6 and a resistor R8, the other end of the resistor R8 is grounded, the other end of the resistor R6 is connected to one end of a resistor R3, the other end of the resistor R3 outputs voltage, the other end of the resistor R3 is connected to the positive electrode of a capacitor C5 and a polar capacitor C4, the other end of the capacitor C5 is grounded, the negative electrode of the polar capacitor C4 is grounded, and when the external voltage is detected to be too high, the external charging circuit is turned off under the control of the mcu.

In this embodiment, as shown in fig. 12, the power management IC circuit includes a charging management IC chip U2, a digital interface VIN end of the charging management IC chip U2 is connected to an anode of a polar capacitor C4, a pin PROG in the charging management IC chip U2 is connected to one end of a resistor R2, the other end of the resistor R2 is grounded, a voltage output terminal VOUT of the charging management IC chip U2 is connected to an interface 1 in the battery BAT, a digital ground VSS in the charging management IC chip U2 is connected to ground, the voltage output terminal VOUT of the charging management IC chip U2 is further connected to a capacitor C3, the other end of the capacitor C3 is connected to ground, and a terminal 2 of the battery BAT is grounded, and a BAT point is located at an interface between the voltage output terminal VOUT of the charging management IC chip U2 and the interface 1 in the battery BAT, so as to provide a charging current for the battery to safely charge the battery.

The charge management IC chip U2 referred to herein is of the MCP73832 model.

IN this embodiment, as shown IN fig. 13, the external power circuit includes a power circuit and an auxiliary power circuit, the power circuit includes a charge management IC chip U1, an input terminal IN of the charge management IC chip U1 is connected to a capacitor C2, an anode of a polar capacitor C9, a cathode of a diode D6 and a cathode of a diode D4, the other end of the capacitor C2 is connected to a cathode of a polar capacitor C9 and grounded, an anode of the diode D6 outputs a voltage, an anode of the diode D4 and a voltage output terminal VOUT of the charge management IC chip U2 are connected to a BAT point at a 1 interface IN the battery BAT, a GND terminal of the charge management IC chip U1 is connected to ground, an output terminal OUT of the charge management IC chip U1 is connected to a capacitor C1 and a power VCC, the other end of the capacitor C1 is grounded, a voltage regulator circuit LDO provides a voltage to the micro control unit, a BAT 39r 38 is connected to a BAT point at a voltage output terminal VOUT of the auxiliary power circuit via a voltage output terminal, the other end of the resistor R1 is connected with the anode of the diode D2, and the cathode of the diode D2 outputs voltage to provide power for the ADC sampling circuit of the port when no external power supply exists.

The charge management IC chip U1 referred to herein is of the KX6209 type.

As shown in fig. 1 to 13, the operation process of the charging alarm control circuit for digital products provided by this embodiment is as follows:

step 1: when the port is not provided with external equipment, Q1 is conducted (S1_ CONA is high level), Q3 and Q4 are not conducted (S1_ CONB is low level), the level of the P1 end is 0, the value detected by the ADC is O, when the port is provided with the external equipment, a pin 1 of the port is +5V, the pin 5 of the port passes through the external equipment, a charging loop is formed by the pin Q1 and the pin D5, the level of the P1 end is 0.3V (determined by the characteristics of the diode), the value detected by the ADC is not 0, and the alarm enters a defense state;

step 2: after entering a defense state, when the value detected by the ADC reaches a preset value, Q3 and Q4 are conducted (S1_ CONB is changed into high level), the charging current flows from pin 1 of the port through the external equipment, then returns to pin 5 of the port, flows through Q3 and resistor 18(0.022R) to the ground, a charging loop is formed, and the charging current is increased (no voltage drop of a diode);

and step 3: and (3) alarm generation: after the entrance of defense, when the external equipment is removed, the voltage at the P1 end becomes 0 (no current flows through D5 or R18), and then an alarm occurs.

In summary, in this embodiment, R3, R6, and R8 in the circuit form a voltage sampling circuit, the sampled voltage is sent to the MCU, when the external voltage is too high (exceeds a preset voltage), the MCU controls the Q1, Q3, and Q4 to be turned off, the external charging current is cut off, so as to perform an overvoltage protection function, after the protection is performed, when Q1, Q3, and Q4 are all turned on, the level detected at the P1 end is the voltage of R18 (the resistance is small, the internal resistance of the MOS transistor is small, so the voltage is small), when the charging current is large (or the load is short), the voltage at R18 is further increased, when the external voltage exceeds the preset value, the MCU controls Q1, Q3, and Q4 to be turned off (S1_ CONA, S1_ CONB is a, and the charging loop at this time is: the charging current of the +5V load port 5 foot-R16, D5 is very little, play the overcurrent protection effect, when overflowing, the ADC detects the voltage that the voltage is the voltage of D5 end, R7 in the circuit, PT1 (thermistor, this resistance welding is on external charging head, be used for surveying the temperature of external charging head and external equipment junction) C8, R10 constitutes the voltage sampling circuit, when detecting that voltage surpasss the predetermined voltage (the temperature of charging head and equipment junction is too high), through MCU's control, cut off external equipment's charging current, play the overtemperature protection. The function is mainly considered that the charging current is not very large, but the temperature of the connection part of the charging head and the external equipment is too high due to other reasons, so that the charging head or the external equipment is burnt out.

The above description is only for the purpose of illustrating the present invention and is not intended to limit the scope of the present invention, and any person skilled in the art can substitute or change the technical solution of the present invention and its conception within the scope of the present invention.

Claims

1. The utility model provides a digital product alarm control circuit that charges, includes little the control unit, bee calling organ drive circuit, wireless module, external power supply voltage detection circuitry, external temperature detection circuitry, power management IC circuit, external power supply circuit, current detection and control circuit and output port, its characterized in that, little the control unit: the system is used for charging control, defense control, alarm control and state display;

a wireless module: the function of wireless receiving is achieved;

2. The digital product charging alarm control circuit of claim 1, wherein: p1.0, P1.1, P1.2, P1.3, P1.4 and P1.5 in the MICRO-control unit are all set as ADC interface terminals, P1.0, P1.1 and P1.2 are respectively connected with AD1 interface terminal in the first current detection and control circuit, AD2 interface terminal in the second current detection and control circuit and AD3 interface terminal in the third current detection and control circuit, P1.3 is connected with a Detector-DC interface terminal in the external power supply voltage detection circuit, P1.4 is connected with the cathode of a light emitting diode D1 through a wire, the anode of a light emitting diode D1 is connected with one end of a resistor R17 through a wire, the other end of the resistor R17 is connected with a power supply VCC through a wire, P1.5 is connected with one end of a resistor R9 in the buzzer drive circuit through a wire, P1.6 and P1.7 in the MICRO-control unit are all set as XTAL ADC terminals, P1.6 is connected with RO and RO of the first current detection and control circuit, wherein the current detection circuit is connected with USB current detection circuit, USB 1.8 and USB detection circuit, wherein, the 6, 7, 8 and 9 terminals of MICRO USB are connected, P5.4 in the MICRO control unit is set as RST interface terminal, and P5.4 is connected with RED2 terminal in the port LED display circuit, P5.5 interface terminal in the MICRO control unit is connected with BLUE2 terminal in the port LED display circuit, P3.2 and P3.3 in the MICRO control unit are both set as INT interface terminal, P3.2 is connected with RED1 terminal in the port LED display circuit, P3.3 is connected with BLUE1 terminal in the port LED display circuit, VCC interface terminal in the MICRO control unit is connected with resistor R5 and capacitor C8655 in parallel through conducting wire, the other end of resistor R5 connected to the other end of capacitor C7 is connected with power supply VCC, interface terminal in the MICRO control unit is grounded, P3.0 in the MICRO control unit is set as RXD interface terminal P3.1 and set as TXD interface terminal, P3.0 is connected with 3 in JP2, the other end of JP 634 is connected with software download port, the SW 364 and SW 12 interface terminal is connected with the other end of the download switch 1 in the download port of JP 3.1, and SW 3.3, The 4 interface of the linkage switch SW and one end of the resistor R14, the other end of the resistor R14 is connected with the power VCC, the 1 interface of the linkage switch SW1 is connected with the 2 interface of the linkage switch SW in parallel and grounded, the 1 interface of the software download port JP2 is connected with the power VCC, the 2 interface of the software download port JP2 is grounded, P2.2 and P2.3 in the micro control unit are respectively connected with the S1CONB and S1 CONA interfaces in the first current detection and control circuit, P2.4 and P2.5 in the micro control unit are respectively connected with the S2 CONB and S2CONA interfaces in the second current detection and control circuit, P2.6 and P2.7 in the micro control unit are respectively connected with the S3 CONB and S3 CONA interfaces in the third current detection and control circuit, the P2.1, P2.0, P3.7, P3.6, P3.5 and P3.4 in the micro control unit are respectively connected with the ports of the wireless module XN1, MISCS 3, SCK 5 and XQ 1 and XQ 2 ports in parallel and IRQ ports in the wireless module 5398, the other end of the resistor R4 is connected with a power supply VCC, and the other end of the capacitor C6 is connected with the wireless module XN1 and grounded.

3. The digital product charging alarm control circuit of any one of claims 1 or 2, wherein: the port LED display circuit comprises a first port LED display circuit and a second port LED display circuit, wherein a resistor R31 is connected in series with RED1 connected with P3.2 in the MICRO control unit in the first port LED display circuit, the other end of the resistor R31 is connected with a base 1 of a transistor Q8, an emitter 2 of the transistor Q8 is grounded, a collector 3 of a transistor Q8 is connected with a cathode of a diode D8, an anode of the diode D8 is connected with a resistor R22, the other end of the resistor R22 is set as an LED R1 end and connected with a 3 terminal of a MICROUSB in the first current detection and control circuit, a resistor R34 is connected in series with BLUE1 connected with P3.3 in the MICRO control unit in the port LED display circuit, the other end of the resistor R34 is connected with the base 1 of the transistor Q10, an emitter 2 of the transistor Q10 is grounded, a collector 3 of the transistor Q10 is connected with a resistor R23 in series, the other end of the resistor R23 is set as an LED B1 and connected with the MICROUSB 2 in the, the RED2 connected with the P5.4 in the MICRO control unit in the second port LED display circuit is connected with a resistor R32 in series, the other end of the resistor R32 is connected with a base 1 of a triode Q9, an emitter 2 of the triode Q9 is grounded, a collector 3 of a triode Q9 is connected with a cathode of a diode D9, an anode of the diode D9 is connected with a resistor R33, the other end of the resistor R33 is set as an LED R2 end and connected with a 3 terminal of MICROUSB in the second current detection and control circuit, BLUE2 connected with the P5.5 in the MICRO control unit in the port LED display circuit is connected with a resistor R35 in series, the other end of the resistor R35 is connected with a base 1 of the triode Q11, an emitter 2 of the triode Q11 is grounded, a collector 3 of the triode Q11 is connected with a resistor R36 in series, and the other end of the resistor R36 is set as an LED B2 and connected with a terminal 2 of.

4. The digital product charging alarm control circuit of any one of claims 1 or 2, wherein: the other end of a resistor R9 connected with P1.5 in the micro control unit in the buzzer driving circuit is connected with a base 1 of a triode Q2, an emitter 2 of the triode Q2 is grounded, a collector 3 of the triode Q2 is connected with a terminal 2 of a buzzer SP1, a terminal 2 of a T1 and one end of a capacitor C10, a terminal 1 of the buzzer is connected with a capacitor C11 in series, the other end of the C11 is grounded, a terminal 3 of the T1 is connected with a terminal 1 of the buzzer, a terminal 1 of the T1 is connected with a VBAT through a conducting wire, and the other end of the capacitor C10 is grounded.

5. The digital product charging alarm control circuit of any one of claims 1 or 2, wherein: the current detection and control circuit comprises a first current detection and control circuit and a second current detection and control circuit, wherein one end of S1 CONA connected with P2.3 in the MICRO control unit in the first current detection and control circuit is connected in series with a resistor R15, the other end of the resistor R15 is connected with a grid electrode in a field effect transistor Q1, a source electrode in the field effect transistor Q1 is connected with an anode of a diode D5, a capacitor C12 and a resistor R16, the other ends of a cathode of a diode D5 and a capacitor C12 are connected with one end of a resistor R18 and are grounded, a drain electrode in the field effect transistor Q1, the other end of the resistor R16 and one end of an instantaneous voltage suppression diode TVS1 are all connected with a 5 terminal of MICROUSB in the first current detection and control circuit, the other end of the instantaneous voltage suppression diode TVS1 is grounded, and the 5 terminal of the MICROUSB in the first current detection and control circuit is connected with a drain electrode of a field effect transistor Q, a source of the field effect transistor Q3 is connected to the other end of the resistor R18 and a drain of the field effect transistor Q4, a gate of the field effect transistor Q3 is connected to one end of the resistor R20, a source of the field effect transistor Q4 is connected to one end of the resistor R38 at a point P1, a gate of the field effect transistor Q4 is connected to one end of the resistor R21, the other end of the resistor R21 is connected to the other end of the resistor R20 at a point S1CONB connected to P2.3 in the MICRO control unit, the other end of the resistor R38 is connected to the capacitor C15, the other end of the capacitor C15 is grounded, a connection point of the resistor R38 and the capacitor C15 is AD1 connected to P1.0 in the MICRO control unit, a 1 connection port of the first current detection and control circuit outputs a direct current of 5V, one end of the S2CONA connected to P2.5 in the MICRO control unit in the second current detection and control circuit is connected in series to one end of the resistor R6342 and the gate of the transistor Q5. The source of the field effect transistor Q5 is connected with anode of diode D7, capacitor C14 and resistor R27, the cathode of diode D7 and another end of capacitor C14 are connected with one end of resistor R28 and grounded, the drain of the diode Q5, another end of resistor R27 and one end of transient voltage suppression diode TVS2 are all connected with 5 terminal of MICROUSB in the second current detection and control circuit, another end of transient voltage suppression diode TVS2 is grounded, and 5 terminal of MICROUSB in the second current detection and control circuit is connected with drain of field effect transistor Q6, the source of field effect transistor Q6 is connected with another end of resistor R28 and drain of field effect transistor Q7, the gate of field effect transistor Q6 is connected with one end of resistor R29, the source of field effect transistor Q7 is connected with one end of resistor R37, and the connection point is P2, the gate of field effect transistor Q7 is connected with one end of resistor R30, the other end of the resistor R30 is connected with the other end of the resistor R29, the connection point is S2 CONB and P2.4 in the MICRO control unit, the other end of the resistor R37 is connected with a capacitor C16, the other end of the capacitor C16 is grounded, the connection point of the resistor R37 and the capacitor C16 is AD2 and is connected with P1.1 in the MICRO control unit, and the 1 connection port of MICRO USB in the second current detection and control circuit outputs 5V direct current voltage.

6. The digital product charging alarm control circuit of any one of claims 1 or 2, wherein: the external temperature detection circuit comprises a first port temperature detection circuit and a second port temperature detection circuit, a PT1 wiring point in the first port temperature detection circuit is connected with a P1.6 in the MICRO control unit and is connected with a capacitor C8, a resistor R10, a thermistor PT1 and a resistor R13, the other ends of the resistors R13, C8 and R10 are connected with each other and grounded, the other end of the thermistor PT1 is connected with an upper resistor R7, the other end of the upper resistor R7 is connected with a power supply, the junction of the thermistor PT1 and the upper resistor R7 is a PT1A wiring point, the PT1A wiring point is connected with a 4 wiring port of a MICROUSB in the first current detection and control circuit, a PT2 wiring point in the second port temperature detection circuit is connected with a P1.7 in the MICRO control unit and is connected with a capacitor C9, a resistor R24, a PT2 and a thermistor R25, a resistor R25, a capacitor C13 and a PT 24 and the other end of the second port temperature detection circuit is connected with a PT 24 and is connected with an upper resistor R11, the other end of the upper resistor R11 is connected with a power supply, the junction of the thermistor PT2 and the upper resistor R11 is a PT2A connection point, and the PT2A connection point is connected with a 4 connection port of MICROUSB in the second current detection and control circuit.

7. The digital product charging alarm control circuit of any one of claims 1 or 2, wherein: the other end of a Detector-DC (direct current) connected with P1.3 in the external power supply voltage detection circuit and the micro control unit is connected with a resistor R6 and a resistor R8, the other end of the resistor R8 is grounded, the other end of the resistor R6 is connected with one end of the resistor R3, the other end of the resistor R3 outputs voltage, the other end of the resistor R3 is connected with the positive electrode of a capacitor C5 and a polar capacitor C4, the other end of the capacitor C5 is grounded, and the negative electrode of the polar capacitor C4 is grounded.

8. The digital product charging alarm control circuit of any one of claims 1 or 2, wherein: the power supply management IC circuit comprises a charging management IC chip U2, a digital interface VIN end of the charging management IC chip U2 is connected with the positive electrode of a polar capacitor C4, a pin PROG in the charging management IC chip U2 is connected with one end of a resistor R2, the other end of the resistor R2 is grounded, a voltage output end VOUT of the charging management IC chip U2 is connected with an interface 1 in a battery BAT, a digital ground VSS in the charging management IC chip U2 is grounded, the voltage output end VOUT of the charging management IC chip U2 is further connected with a capacitor C3, the other end of the capacitor C3 is grounded, a terminal 2 of the battery BAT is grounded, and the voltage output end VOUT of the charging management IC chip U2 and the interface 1 in the battery BAT are used as a BAT point.

9. The digital product charging alarm control circuit of any one of claims 1 or 2, wherein: the external power supply circuit comprises a power supply circuit and an auxiliary power supply circuit, the power supply circuit comprises a charge management IC chip U1, an input end IN of the charge management IC chip U1 is connected with a capacitor C2, a positive electrode of a polar capacitor C9, a cathode of a diode D6 and a cathode of a diode D4, the other end of the capacitor C2 is connected with a negative electrode of a polar capacitor C9 and grounded, an anode of a diode D6 outputs voltage, an anode of a diode D4 and a voltage output end VOUT of the charge management IC chip U2 are connected with a 1-interface BAT IN a battery BAT, a ground end GND of the charge management IC chip U1 is connected with ground, an output end OUT of the charge management IC chip U1 is connected with a capacitor C1 and a power VCC, the other end of the capacitor C1 is grounded, a resistor R1 is connected with the 1-interface BAT IN the auxiliary power supply circuit through the voltage output end VOUT of the charge management IC chip U2, the other end of the resistor, the cathode of the diode D2 outputs a voltage.