CN210744819U

CN210744819U - Power supply control circuit and terminal equipment

Info

Publication number: CN210744819U
Application number: CN201921437349.6U
Authority: CN
Inventors: 胡东平
Original assignee: Shenzhen Neoway Technology Co Ltd
Current assignee: Shenzhen Neoway Technology Co Ltd
Priority date: 2019-08-30
Filing date: 2019-08-30
Publication date: 2020-06-12
Anticipated expiration: 2029-08-30

Abstract

The embodiment of the utility model discloses power control circuit and have this circuit control circuit's terminal equipment. The power supply control circuit comprises a main power supply, a voltage conversion chip, a standby power supply and a control chip; the voltage conversion chip controls the main power supply voltage received by the input end to be converted into load voltage, and outputs the load voltage through the output end; the standby power supply is connected to the output end of the voltage conversion chip through a diode; the control chip is used for controlling the charging operation of the standby power supply. The utility model discloses it is stolen and continue to provide load voltage by stand-by power supply when can't providing load voltage at the main power supply, so, can still realize locate function when the main power supply is stolen.

Description

Power supply control circuit and terminal equipment

Technical Field

The utility model relates to an electronic circuit field especially relates to a power control circuit and have this power control circuit's terminal equipment.

Background

The Tracker terminal has become an important terminal device for internet of things and vehicle networking, has the functions of GPS positioning, information acquisition and transmission and the like, and is applied to various industries. For example: the system is typically applied to the vehicle-mounted (motorcycle, electric vehicle or automobile and the like) industry to realize the functions of GPS/LBS positioning, anti-theft alarm, positioning tracking, track query and the like. When the Tracker terminal is applied to the in-vehicle device, the battery on the in-vehicle device is connected to the Tracker terminal so that power is supplied from the battery of the in-vehicle device. However, when the storage battery on the vehicle-mounted device is stolen, the positioning function of the Tracker terminal is lost under the condition that power is not supplied, and the use range of the Tracker terminal is reduced.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a power control circuit and have this power control circuit's terminal equipment can still realize locate function when the battery on the mobile unit is stolen.

The first aspect of the present embodiment provides a power control circuit, including:

a main power supply outputting a main power supply voltage;

the voltage conversion chip comprises an input end and an output end, the input end of the voltage conversion chip is connected to the main power supply, and the voltage conversion chip is used for controlling the main power supply voltage to be converted into load voltage and outputting the load voltage through the output end;

the standby power supply is connected to the output end of the voltage conversion chip through a diode;

the control chip comprises a first pin and a second pin, and the first pin of the control chip is connected to the output end of the voltage conversion chip through a first resistor; the first pin of the control chip is also connected to the first end of the control switch; the second end of the control switch is connected to a second pin of the control chip, and the second end of the control switch is grounded through a second resistor; the third end of the control switch is connected to the first end of the regulating switch through a third resistor; the second end of the adjusting switch is connected to the output end of the voltage conversion chip, and the third end of the adjusting switch is connected to the standby power supply through a fourth resistor; when the first end of the control switch is at a high level, the second end and the third end of the control switch are in a conducting state; when the first end of the control switch is at a low level, the second end and the third end of the control switch are in a cut-off state; when the first end of the adjusting switch is at a low level, the second end and the third end of the adjusting switch are in a conducting state; and when the first end of the adjusting switch is at a high level, the second end and the third end of the adjusting switch are in a cut-off state.

In an embodiment, the control switch is an N-channel fet, a first end of the control switch is a gate of the N-channel fet, a second end of the control switch is a source of the N-channel fet, and a third end of the control switch is a drain of the N-channel fet.

In an embodiment, the adjustment switch is a PNP type triode, the first end of the adjustment switch is a base of the PNP type triode, the second end of the adjustment switch is an emitter of the PNP type triode, and the third end of the adjustment switch is a collector of the PNP type triode.

In an embodiment, an anode of the standby power supply is connected to the fourth resistor, the anode of the standby power supply is further connected to an anode of the diode, a cathode of the diode is connected to the output end of the voltage conversion chip, and a cathode of the standby power supply is grounded.

In one embodiment, the backup power source includes a rechargeable battery or a super capacitor.

In an embodiment, the control chip controls the first pin to output a high-voltage control signal to the first end of the control switch, and the control chip further controls the second pin to output a pulse signal to the first end of the adjustment switch.

In an embodiment, the control chip further includes a sampling pin, and the sampling pin is connected to two ends of the fourth resistor; the control chip acquires the sampling voltage of the standby power supply according to the sampling pin and inputs a corresponding pulse signal to the first end of the adjusting switch according to the sampling voltage so as to control the charging current of the standby power supply.

In an embodiment, the control chip further determines whether the sampling voltage changes within a preset time, and when the sampling voltage does not change within the preset time, the control chip determines that the state of the standby power supply is abnormal, and outputs warning information when the state of the standby power supply is abnormal.

In an embodiment, the control chip further determines a charging stage where the standby power supply is charged according to the sampling voltage, and transmits a corresponding pulse signal to the first end of the adjustment switch based on the determined charging stage.

The embodiment of the utility model provides a second aspect provides a terminal equipment, including load circuit with the utility model provides an arbitrary power control circuit of first aspect, the output of the voltage conversion chip among the power control circuit connect in load circuit.

The power supply control circuit and the terminal equipment with the power supply control circuit can continuously provide the load voltage by the standby power supply when the main power supply is stolen and cannot provide the load voltage, so that the positioning function can be still realized when the main power supply is stolen.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic circuit connection diagram of a terminal device having a power control circuit according to an embodiment of the present invention.

Detailed Description

In order to make the technical solution of the present invention better understood, the technical solution of 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, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

The terms "first," "second," and the like in the description and in the claims, and in the drawings described above, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The embodiments of the present invention will be described in detail below.

Referring to fig. 1, a schematic circuit connection diagram of a terminal device having a power control circuit according to an embodiment of the present invention is shown. The terminal device 90 may include a power control circuit 50 and a load circuit 30 that supplies power to the system circuit 30 through the power control circuit 50. In this embodiment, the power control circuit 50 may include a main power source 40, a standby power source 60, and a control chip 20; the load circuit 30 may include a radio frequency circuit, wherein the radio frequency circuit may include a wireless radio frequency circuit and a GPS radio frequency circuit. The control chip 20 may communicate with an external server through a network supported by the wireless rf circuit of the load circuit 30, including but not limited to a 2G, 3G, 4G, 5G or WiFi network, and the control chip 20 may also perform positioning through a GPS rf circuit, such as obtaining current longitude information and latitude information of the terminal device 90.

In this embodiment, the terminal device 90 may be an in-vehicle device, the main power supply 40 may be a battery, and the main power supply 40 may output a main power supply voltage. The power control circuit 50 further includes a voltage conversion chip 10 connected between the main power source 40 and the load circuit 30, wherein the voltage conversion chip 10 includes an input end and an output end, the input end of the voltage conversion chip 10 is connected to the main power source 40, and the output end of the voltage conversion chip 10 is connected to the load circuit 30. When the main power source 40 is placed in a predetermined position of the terminal device 90, the voltage conversion chip 10 may convert the main power source voltage into the load voltage since the main power source voltage input by the main power source 40 may not match the load voltage required by the load circuit 30. For example, when the load voltage corresponding to the load circuit 30 is 4.2V, the voltage conversion chip 10 may convert the main power voltage greater than the load voltage into 4.2V.

In this embodiment, since the power control circuit 50 further includes the backup power source 60, when the main power source 40 of the terminal device 90 is stolen or removed, the power control circuit 50 can supply power to the load circuit 30 and the control chip 20 through the backup power source 60 to continue providing the positioning function without the main power source 40. The backup power source 60 may be a rechargeable device such as a battery or a super capacitor.

In this embodiment, the power control circuit 50 further includes a charging circuit, and the control chip 20 charges the backup power source 60 from the main power source 40 by controlling the charging circuit, so that the backup power source 60 can still provide the load voltage required by the load circuit 30 without the main power source 40.

In this embodiment, the charging circuit may include a control switch Q1, an adjustment switch Q2, and resistors R1-R4, wherein:

the first pin GPIO1 of the control chip 20 is connected to the load circuit 30 through a resistor R1, and the first pin GPIO1 is also connected to a first terminal of the control switch Q1. The second end of the control switch Q1 is connected to the second pin GPIO2 of the control chip 20, and is also grounded through a resistor R3; the third terminal of the control switch Q1 is connected to the first terminal of the regulating switch Q2 through a resistor R2. The second terminal of the adjusting switch Q2 is connected to the load circuit 30, and the third terminal of the adjusting switch Q2 is connected to the backup power supply 60 through the resistor R4, for example, the positive terminal of the backup power supply 60 is connected, and the negative terminal of the backup power supply 60 is grounded.

In this embodiment, the control switch Q1 may be an N-channel fet, and the first terminal, the second terminal, and the third terminal of the control switch Q1 are respectively a gate, a source, and a drain of the N-channel fet, that is, when the first terminal of the control switch Q1 is at a high level, the second terminal and the third terminal of the control switch Q1 are in a conducting state; when the first terminal of the control switch Q1 is at a low level, the control switch Q1 is in a cut-off state between the second terminal and the third terminal; the regulating switch Q2 is a PNP type triode, and the first, second, and third terminals of the regulating switch Q2 are the base, emitter, and collector of the PNP type triode, respectively, that is, when the first terminal of the regulating switch Q2 is at a low level, the second terminal and the third terminal of the regulating switch Q2 are in a conducting state; when the first terminal of the adjusting switch Q2 is at a high level, the second terminal and the third terminal of the adjusting switch Q2 are in a cut-off state. In other embodiments, the control switch Q1 and the adjustment switch Q2 may be replaced by electronic switches with a type function.

The control chip 20 further includes a sampling pin ADC connected to two ends of the resistor R4, and the control chip 20 determines a sampling voltage of the standby power supply 60 through the sampling pin ADC and controls a charging current to the standby power supply 60 based on the determined sampling voltage.

In an embodiment, the control chip 20 further determines the operating state of the backup power supply 60 according to the sampling voltage obtained by the sampling pin, for example, when the sampling voltage obtained by the control chip 20 and corresponding to the backup power supply 60 does not change within a preset time (for example, the sampling voltage obtained by the control chip 20 and corresponding to the backup power supply 60 is less than 3.8V within 12 hours), it indicates that the backup power supply 60 is in an abnormal state, for example, a "dead battery" phenomenon may occur in the backup power supply 60. At this time, the control chip 20 outputs the warning information to the server through the load circuit 30, or outputs the warning information to the device (such as a mobile phone) of the user, etc., to prompt the user to replace the backup power supply 60.

In this embodiment, when the standby power supply 60 is charged, the control chip 20 controls the first pin GPIO1 to output a high-level control signal, so as to control the control switch Q1 to be in a conducting state; the control chip 20 controls the second pin GPIO2 to output a corresponding pulse signal to adjust the conduction degree of the switch Q2 based on the voltage determined by the sampling pin, so as to control the magnitude of the charging current of the standby power supply 60.

In a specific charging process, if the backup power supply 60 is a lithium battery, the control chip 20 may further obtain a sampling voltage and a charging current of the backup power supply 60 through a sampling pin, so as to determine a charging stage of the backup power supply 60 when the backup power supply 60 is charged according to the obtained sampling voltage, for example, determine that the backup power supply 60 is in a trickle charging stage, a constant voltage charging stage, or a constant current charging stage. Then, the control chip 20 may output the PWM waveform of the corresponding charging stage through the second pin GPIO2, so as to control the charging current to satisfy the charging characteristic curve of the lithium battery.

For example, charging at a constant current in the first stage of constant-current constant-voltage charging; when the voltage reaches a preset value, the second stage is carried out to carry out constant voltage charging, and the current is gradually reduced; when the charging current reaches zero, the battery is fully charged.

In one embodiment, when a lithium battery is used as the backup power source, the battery capacity of the lithium battery is generally small and frequent charging and discharging is not required. Therefore, the management of charging the lithium battery can be simplified. For example, the control chip 20 may set the second pin GPIO2 to a high impedance state or a high level, so that the adjusting switch Q2 is in an off state, at which time, a maximum charging current may be set through the resistors R2 and R3, wherein the maximum charging current may be expressed as: icharge (max) — (4.2V-Vbe)/(R2+ R3), where Vbe is the voltage drop of the adjustment switch Q2, and 4.2V is the converted load voltage output by the main power supply 40. When the charging function needs to be turned off, the control chip 20 may output a low level through the first pin GPIO1 to set the Q1 to an off state, where the charging function is turned off.

In one embodiment, the positive terminal of the backup power source 60 is also connected to the load circuit 30 through a diode D1, such that the backup power source 60 can provide the load voltage to the load circuit 30 through a diode D1. For example, the anode of the backup power supply 60 is connected to the anode of the diode D1, and the cathode of the diode D1 is connected to the load circuit 30, so that the backup power supply 60 can provide the load voltage to the load circuit 30 through the diode D1.

In one embodiment, the load voltage obtained after the voltage conversion operation of the voltage conversion chip 10 is performed on the main power source 60 is kept constant. When the load circuit 30 has a transient current demand, the main power source 40 may output a transient current which is insufficient, and at this time, the backup battery 60 may also freewheel the load circuit 30 through the diode D1, thereby implementing the function of dynamic path management of the backup power source.

In one embodiment, in the event of an anomaly in the main power supply 40, such as a stolen electric vehicle or bicycle battery, the main power supply 40 will not output power. At this time, the standby power supply 60 may supply power to the load circuit 30 through the diode D1. The control chip 20 may also check whether the main power source 40 is lost or in a predetermined position (e.g., by detecting whether the power source 40 is in the predetermined position via a sensor) when the backup power source 60 supplies power, and send a main power source (stolen) loss message to the cloud server via the load circuit 30 when the main power source 40 is lost or in the predetermined position, so as to alert the user.

The terminal equipment with the power supply control circuit can continuously provide the load voltage by the standby power supply when the main power supply is stolen and cannot provide the load voltage, so that the positioning function can be still realized when the main power supply is stolen.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

The embodiments of the present invention have been described in detail, and the principles and embodiments of the present invention have been explained herein using specific embodiments, and the above description of the embodiments is only used to help understand the method and the core idea of the present invention; meanwhile, for the general technical personnel in the field, according to the idea of the present invention, there are changes in the specific implementation and application scope, to sum up, the content of the present specification should not be understood as the limitation of the present invention.

Claims

1. A power supply control circuit, comprising:

a main power supply outputting a main power supply voltage;

2. The power control circuit of claim 1, wherein the control switch is an N-channel fet, the first terminal of the control switch is a gate of the N-channel fet, the second terminal of the control switch is a source of the N-channel fet, and the third terminal of the control switch is a drain of the N-channel fet.

3. The power control circuit of claim 1, wherein the regulating switch is a PNP transistor, the first terminal of the regulating switch is a base of the PNP transistor, the second terminal of the regulating switch is an emitter of the PNP transistor, and the third terminal of the regulating switch is a collector of the PNP transistor.

4. The power control circuit of claim 1, wherein an anode of the backup power source is connected to the fourth resistor, the anode of the backup power source is further connected to an anode of the diode, a cathode of the diode is connected to the output terminal of the voltage conversion chip, and a cathode of the backup power source is grounded.

5. The power control circuit of claim 4, wherein the backup power source comprises a rechargeable battery or a super capacitor.

6. The power control circuit as claimed in claim 1, wherein the control chip controls the first pin to output a high-voltage control signal to the first terminal of the control switch, and the control chip further controls the second pin to output a pulse signal to the first terminal of the adjustment switch.

7. The power control circuit of claim 6, wherein the control chip further comprises a sampling pin, the sampling pin being connected to both ends of the fourth resistor; the control chip acquires the sampling voltage of the standby power supply according to the sampling pin and inputs a corresponding pulse signal to the first end of the adjusting switch according to the sampling voltage so as to control the charging current of the standby power supply.

8. The power control circuit according to claim 7, wherein the control chip further determines whether the sampling voltage changes within a preset time, and when the sampling voltage does not change within the preset time, the control chip determines that the state of the backup power supply is abnormal, and outputs warning information when the state of the backup power supply is abnormal.

9. The power control circuit of claim 7, wherein the control chip further determines a charging phase during charging of the backup power supply according to the sampled voltage, and transmits a corresponding pulse signal to the first terminal of the adjustment switch based on the determined charging phase.

10. A terminal device, comprising a power control circuit and a load circuit, wherein the power control circuit is the power control circuit of any one of claims 1 to 9, and an output terminal of a voltage conversion chip in the power control circuit is connected to the load circuit.