CN115940382A

CN115940382A - Standby power charging device and vehicle-mounted LCD (liquid Crystal display) play controller standby power system

Info

Publication number: CN115940382A
Application number: CN202211583033.4A
Authority: CN
Inventors: 陈成; 唐日元; 田华; 张上友; 周剑
Original assignee: Guangdong Huazhiyuan Information Engineering Co ltd; Guangzhou Huajia Software Co ltd; Guangzhou Jiadu Urban Rail Intelligent Operation And Maintenance Service Co ltd; PCI Technology and Service Co Ltd
Current assignee: Guangdong Huazhiyuan Information Engineering Co ltd; Guangzhou Huajia Software Co ltd; Guangzhou Jiadu Urban Rail Intelligent Operation And Maintenance Service Co ltd; PCI Technology and Service Co Ltd
Priority date: 2022-12-09
Filing date: 2022-12-09
Publication date: 2023-04-07

Abstract

The invention discloses a standby power charging device and a standby power system of a vehicle-mounted LCD (liquid crystal display) play controller, wherein the standby power charging device comprises a main loop and a control loop, the main loop comprises an EMC (electro magnetic compatibility) unit, a first filtering unit, a Buck-Boost unit, a second filtering unit, a first overcurrent protection unit and a second overcurrent protection unit, and the control loop comprises a control IC (integrated circuit), a soft start unit, a Boost unit and a voltage regulation unit. In the invention, the first overcurrent protection unit is connected between the first filtering unit and the Buck-Boost unit to detect the current, so that the quick and reliable short-circuit protection can be realized, meanwhile, the second overcurrent protection unit is connected between the Buck-Boost unit and the second filtering unit to detect the current, so that the quick and reliable short-circuit protection can be realized, the two overcurrent protection units are independent from each other, so that the input and output currents in the standby power charging device are protected, and the current detection cost is favorably reduced and the current detection time delay is favorably shortened.

Description

Standby power charging device and vehicle-mounted LCD (liquid Crystal display) play controller standby power system

Technical Field

The invention relates to the technical field of charging equipment, in particular to a standby power charging device and a standby power system of a vehicle-mounted LCD (liquid crystal display) play controller.

Background

The conventional super capacitor bank needs to be charged by a charging circuit in the energy storage process, the common charging circuit is a DC/DC conversion circuit, and the common DC/DC conversion circuits include three types: buck, buck-Boost, wherein Buck-Boost (Buck-Boost) circuits are often used in chargers in various types of power systems. However, the charging circuit applied to the super capacitor bank in the standby power system of the vehicle-mounted LCD player controller needs to meet the requirements of the AEQ-100 standard of the vehicle, and protection circuits need to be added at the input end and the output end of the charging circuit.

In the prior art, a fuse is generally connected to an input loop and an output loop, or a current sensor connected in series with an inductor is added to a Buck-Boost circuit. If the mode of accessing the fuse is adopted, although the purpose of short-circuit protection can be achieved, the cost is high, in addition, the reaction time of the fuse is slow, and the short-circuit current generated before protection can damage the super capacitor bank. Once the fuse is disconnected, the fuse has the characteristic of non-recovery, and the disconnection and maintenance are required after protection, so that the cost is high. And a current sensor connected in series with the inductor is added in the Buck-Boost circuit, the current sensor can be a hall element or an electromagnetic element, and the current sensor can detect the inductive current flowing through the inductor and output a current detection signal to indicate the magnitude of the current inductive current. However, the current sensor has a high cost, which is not favorable for saving the cost, and the detection time delay of the current sensor is long, so that the application range of the detection result is limited. In addition, the Buck-Boost circuit adopts a topological structure of an H bridge, so that a large impact current can be caused in the starting process, not only can the switching devices in the H bridge be damaged, but also the service life of the Buck-Boost circuit can be reduced, and the topological structure of the H bridge can increase the conduction loss in the conducting process of an upper bridge arm.

Disclosure of Invention

In order to overcome the defects of the prior art, one of the objectives of the present invention is to provide a charging device for a backup power supply, which can solve the problem that when a Buck-Boost circuit is used for charging a super capacitor bank, there is an obvious current detection delay and effective protection cannot be formed on a device.

The second objective of the present invention is to provide a standby power system for a vehicle-mounted LCD display controller, which can solve the problems of short service life and high failure rate of the charging circuit of the conventional standby power system for a vehicle-mounted LCD display controller.

In order to achieve one of the above purposes, the technical scheme adopted by the invention is as follows:

the utility model provides a standby power charging device, includes major loop and control circuit, the major loop includes EMC unit, first filter unit, buck-Boost unit, second filter unit, first overcurrent protection unit and second overcurrent protection unit, control circuit includes control IC, soft start unit, the unit of stepping up and voltage regulation unit, the output of EMC unit is connected with the input of first filter unit, the output of first filter unit and the input of Buck-Boost unit all are connected with first overcurrent protection unit, the output of Buck-Boost unit and the input of second filter unit all are connected with second overcurrent protection unit, soft start unit, voltage regulation unit, the unit of stepping up, buck-Boost unit, first overcurrent protection unit and second overcurrent protection unit all are connected with control IC, buck-Boost unit is connected with the unit of stepping up.

Preferably, the first filtering unit includes a capacitor C18, a capacitor C19, a capacitor C20, a capacitor C21, a capacitor C22, and a capacitor C23, the output terminal of the EMC unit, one end of the capacitor C18, one end of the capacitor C19, one end of the capacitor C20, one end of the capacitor C21, one end of the capacitor C22, one end of the capacitor C23, the first overcurrent protection unit, and the fourth pin CSP1 of the control IC are all connected to the fifth pin IN of the control IC, and the other end of the capacitor C18, the other end of the capacitor C19, the other end of the capacitor C20, the other end of the capacitor C21, the other end of the capacitor C22, and the other end of the capacitor C23 are commonly grounded.

Preferably, the first overcurrent protection unit includes a sampling resistor RS1, the output end of the EMC unit, one end of the capacitor C18, one end of the capacitor C19, one end of the capacitor C20, one end of the capacitor C21, one end of the capacitor C22, one end of the capacitor C23, a fourth pin CSP1 of the control IC, and a fifth pin IN of the control IC are all connected to one end of the resistor RS1, and the input end of the Buck-Boost unit and the third pin CSN1 of the control IC are all connected to the other end of the resistor RS 1.

Preferably, the Buck-Boost unit includes a MOS transistor Q1, a MOS transistor Q2, a MOS transistor Q3, a MOS transistor Q4, a power inductor L4, a resistor R13, a resistor R14, a resistor R15, and a resistor 16, the other ends of a third pin CSN1 and a resistor RS1 of the control IC are connected to the drain of the MOS transistor Q1, the gate of the MOS transistor Q1 is connected to a twenty-third pin DH1 of the control IC through the resistor R14, one end of the Boost unit, the power inductor L4, and the drain of the MOS transistor Q3 are connected to the source of the MOS transistor Q1, the gate of the MOS transistor Q3 is connected to a first pin DL1 of the control IC through the resistor R16, the source of the MOS transistor Q3 is grounded, the fifteenth pin CSP2 of the second overcurrent protection unit and the control IC are connected to the drain of the MOS transistor Q2, the gate of the MOS transistor Q2 is connected to a twentieth pin DH2 of the control IC through the resistor R13, the other end of the power inductor L4, the source of the Boost unit and the transistor Q4 are connected to the drain of the MOS transistor Q2, and the drain of the MOS transistor Q4 are connected to the drain of the control IC through the drain of the eighteenth pin Q2, and the drain of the transistor Q2, and the gate of the transistor Q2.

Preferably, the second overcurrent protection unit includes a sampling resistor RS2, the drain of the MOS transistor Q2 and the fifteenth pin CSP2 of the control IC are both connected to one end of the sampling resistor RS2, and the fourteenth pin CSN2 of the control IC, the thirteenth pin OUT of the control IC, and the input end of the second filtering unit are all connected to the other end of the sampling resistor RS 2.

Preferably, the second filtering unit includes a capacitor C24, a capacitor C25, a capacitor C26, a capacitor C27, and a capacitor C28, one end of the capacitor C24, one end of the capacitor C25, one end of the capacitor C26, one end of the capacitor C27, one end of the capacitor C28, the voltage adjusting unit, the fourteenth pin CSN2 of the control IC, and the thirteenth pin OUT of the control IC are all connected to the other end of the sampling resistor RS2, and the other end of the capacitor C24, the other end of the capacitor C25, the other end of the capacitor C26, the other end of the capacitor C27, and the other end of the capacitor C28 are commonly grounded.

Preferably, the soft start unit includes a resistor R24, the boost unit includes a capacitor C15, a capacitor C16, a resistor R17, a resistor R18, and a rectifier bridge D10, the voltage regulation unit includes a resistor R22, a resistor R28, and a resistor R30, the ninth pin FSW of the control IC is grounded through the resistor R24, one end of the power inductor L4, the drain of the MOS transistor Q3, and the source of the MOS transistor Q1 are all connected to one end of the capacitor C15, the other end of the power inductor L4, the drain of the MOS transistor Q4, and the source of the MOS transistor Q2 are all connected to one end of the capacitor C16, the other end of the capacitor C15 and one end of the resistor R17 are all connected to the first output terminal of the rectifier bridge D10, the other end of the capacitor C16 and one end of the resistor R18 are all connected to the second output terminal of the rectifier bridge D10, the other end of the resistor R17 is connected to the twenty-fourth pin BST1 of the control IC, the other end of the resistor R18 is connected to the tenth pin BST2 of the control IC, the other end of the ninth pin D10 is connected to the seventeenth pin of the resistor R22, one end of the resistor R28 is connected to one end of the first pin FB of the resistor C22, one end of the resistor R28 is connected to one end of the resistor R28, and one end of the resistor R28 of the resistor R22 are connected to the resistor R28, and one end of the resistor R30 are connected to the resistor R30.

Preferably, the current limiting unit further comprises a sampling resistor RS3, a resistor R5, a sliding rheostat R6, a resistor R7, a resistor R8, a capacitor C6, a light emitting diode LED1 and an operational amplifier U4, wherein one end of the capacitor C24, one end of the capacitor C25, one end of the capacitor C26, one end of the capacitor C27, one end of the capacitor C28 and one end of the resistor R22 are all connected to one end of the sampling resistor RS3, the other end of the sampling resistor RS3 is connected to a forward input end of the operational amplifier U4, one end of the resistor R5 is connected to one end of the resistor R7, the other end of the resistor R5 is connected to one end of the sliding rheostat R6, the other end of the resistor R7, one end of the resistor R8, one end of the capacitor C6 and a sliding end of the sliding rheostat R6 are all connected to a reverse input end of the operational amplifier U4, the other end of the resistor R8 and the other end of the sliding rheostat R6 are grounded, the other end of the capacitor C6 and an anode of the light emitting diode LED1 are all connected to an output end of the operational amplifier U4, and a cathode of the light emitting diode control pin of the LED1 is connected to the eighth control pin of the operational amplifier IC 1.

In order to achieve the second purpose, the technical scheme adopted by the invention is as follows:

the utility model provides a vehicle-mounted LCD play controller stand-by power supply system, includes redundancy switch module, DC/DC charging module and super capacitor group module, DC/DC charging module includes such as above-mentioned stand-by power supply charging device, the output of redundancy switch module and the output of super capacitor group module all are connected with vehicle-mounted LCD play controller's input, the input of super capacitor group module is passed through stand-by power supply charging device and is connected with the output of redundancy switch module.

Compared with the prior art, the invention has the beneficial effects that: the front-end lightning surge is protected through an EMC unit, meanwhile, the first filtering unit and the second filtering unit are respectively used as filtering circuits of an input end and an output end of a standby power charging device to reduce ripples of the whole circuit, the Buck-Boost unit is used as a topological circuit of a main loop, the first overcurrent protection unit is connected between the first filtering unit and the Buck-Boost unit and can detect current to realize quick and reliable short-circuit protection, the second overcurrent protection unit is connected between the Buck-Boost unit and the second filtering unit and can also detect current to realize quick and reliable short-circuit protection, the two overcurrent protection units are independent from each other, the control IC is used as a core component of the standby power charging device to play a role in controlling charging of energy storage equipment, the soft start unit is connected with the control IC and can effectively reduce impact current caused by the circuit in the starting process and is determined through a fixed-frequency auxiliary oscillator, in addition, the voltage regulation unit samples output voltage of the second filtering unit and feeds the sampled output voltage back to the control IC to control the PWM output unit in the control IC to further regulate Buck-Boost unit; furthermore, the control IC controls the boosting unit to improve the driving voltage in the Buck-Boost unit, and the Buck-Boost unit is boosted and driven when the driving voltage is insufficient in the Buck-Boost unit

Drawings

Fig. 1 is a schematic structural diagram of a charging device of a backup power supply according to a first embodiment.

Fig. 2 is a circuit diagram of the backup power charging apparatus according to the present invention.

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

Fig. 4 is a circuit diagram of the current limiting unit according to the second embodiment.

Fig. 5 is a schematic structural diagram of a standby power supply system of a vehicle-mounted LCD playback controller according to a third embodiment.

Fig. 6 is a circuit diagram of the equalizing unit according to the third embodiment.

Detailed Description

The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

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

The invention will be further described with reference to the accompanying drawings and the detailed description below:

in the invention, the standby power supply charging device can be applied to charging of energy storage equipment under various scenes, preferably, the energy storage equipment is a standby power supply, specifically, the input end of the standby power supply charging device is connected with a power supply, and the output end of the standby power supply charging device is connected with the energy storage equipment, so that the power supply is transmitted to the energy storage equipment for energy storage. Further, the control IC may be a logic circuit capable of generating a control signal, such as: a general purpose central processing unit CPU, a digital signal processor DSP, an application specific integrated circuit ASIC, a field programmable gate array FPGA, a microcontroller MCU or other programmable logic device, a transistor logic device, a hardware component, or any combination thereof.

The first embodiment is as follows:

as shown in fig. 1-2, a standby power charging device includes a main circuit and a control circuit, the main circuit includes an EMC unit, a first filtering unit, a Buck-Boost unit, a second filtering unit, a first overcurrent protection unit and a second overcurrent protection unit, the control circuit includes a control IC, a soft start unit, a Boost unit and a voltage regulation unit, an output end of the EMC unit is connected with an input end of the first filtering unit, an output end of the first filtering unit and an input end of the Buck-Boost unit are both connected with the first overcurrent protection unit, an output end of the Buck-Boost unit and an input end of the second filtering unit are both connected with the second overcurrent protection unit, the soft start unit, the voltage regulation unit, the Boost unit, the Buck-Boost unit, the first overcurrent protection unit and the second overcurrent protection unit are all connected with the control IC, and the Buck-Boost unit is connected with the Boost unit. In this embodiment, the first overcurrent protection unit is connected between the first filtering unit and the Buck-Boost unit, so as to detect the current, and realize quick and reliable short-circuit protection, and the second overcurrent protection unit is connected between the Buck-Boost unit and the second filtering unit, so as to detect the current, so as to realize quick and reliable short-circuit protection.

Preferably, the EMC unit is preferably an EMC circuit, which is an electromagnetic compatibility circuit, and an EMC filter is optionally used for protecting a front-end lightning surge. The first filtering unit and the second filtering unit are respectively used as filtering circuits of an input end and an output end of a standby power charging device to reduce ripples of the whole circuit, the Buck-Boost unit is used as a topological circuit of a main loop, the first overcurrent protection unit is connected between the first filtering unit and the Buck-Boost unit and has a function of detecting current to realize quick and reliable short-circuit protection, meanwhile, the second overcurrent protection unit is connected between the Buck-Boost unit and the second filtering unit and also has a function of detecting current to realize quick and reliable short-circuit protection, the two overcurrent protection units are independent from each other and cannot influence each other, the control IC is used as a core component of the standby power charging device to play a role of controlling charging of energy storage equipment, the soft start unit is connected with the control IC and can effectively reduce impact current caused by the circuit in the starting process and is determined by a fixed frequency auxiliary oscillator, in addition, the voltage regulation unit samples the output voltage of the second filtering unit and feeds the sampled output voltage back to the control IC, and the Buck-Boost unit is controlled by the duty ratio of output PWM (pulse width modulation) in the control IC to regulate the output voltage; furthermore, the control IC controls the boosting unit to improve the driving voltage in the Buck-Boost unit, and the Buck-Boost unit is boosted and driven when the driving voltage is insufficient in the Buck-Boost unit.

Specifically, the first filtering unit includes a capacitor C18, a capacitor C19, a capacitor C20, a capacitor C21, a capacitor C22, and a capacitor C23, the output terminal of the EMC unit, one end of the capacitor C18, one end of the capacitor C19, one end of the capacitor C20, one end of the capacitor C21, one end of the capacitor C22, one end of the capacitor C23, the first overcurrent protection unit, and the fourth pin CSP1 of the control IC are all connected to the fifth pin IN of the control IC, and the other end of the capacitor C18, the other end of the capacitor C19, the other end of the capacitor C20, the other end of the capacitor C21, the other end of the capacitor C22, and the other end of the capacitor C23 are commonly grounded. Preferably, the first overcurrent protection unit includes a sampling resistor RS1, the output end of the EMC unit, one end of the capacitor C18, one end of the capacitor C19, one end of the capacitor C20, one end of the capacitor C21, one end of the capacitor C22, one end of the capacitor C23, a fourth pin CSP1 of the control IC, and a fifth pin IN of the control IC are all connected to one end of the resistor RS1, and the input end of the Buck-Boost unit and the third pin CSN1 of the control IC are all connected to the other end of the resistor RS 1. In this embodiment, the Buck-Boost unit may be replaced by a Buck converter, a Buck-Boost converter or a Boost converter, where the Buck-Boost converter may Boost or Buck voltage by using the same circuit according to application, and the number of capacitors connected in series may be selected by a super capacitor bank in the standby power supply system of the vehicle-mounted LCD player controller according to specific requirements of a project, so that the Buck-Boost with adjustable output voltage is selected as a preferred option, and a topology with an H bridge is adopted in the Buck-Boost circuit as a preferred option, and the topology with the H bridge has advantages that a series of conventional Buck-Boost circuits do not have, such as frequency multiplication, small energy storage inductance, same polarity of input and output voltages, wide input and output voltages, and the like. Specifically, the Buck-Boost unit comprises a MOS transistor Q1, a MOS transistor Q2, a MOS transistor Q3, a MOS transistor Q4, a power inductor L4, a resistor R13, a resistor R14, a resistor R15 and a resistor 16, the other ends of a third pin CSN1 and a resistor RS1 of the control IC are connected to the drain of the MOS transistor Q1, the gate of the MOS transistor Q1 is connected to a twenty-third pin DH1 of the control IC through the resistor R14, one end of the Boost unit, the power inductor L4 and the drain of the MOS transistor Q3 are connected to the source of the MOS transistor Q1, the gate of the MOS transistor Q3 is connected to a first pin DL1 of the control IC through the resistor R16, the source of the MOS transistor Q3 is grounded, the fifteenth pin CSP2 of the second overcurrent protection unit and the control IC are connected to the drain of the MOS transistor Q2, the gate of the MOS transistor Q2 is connected to a twentieth pin DH2 of the control IC through the resistor R13, the other end of the power inductor L4 and the source of the MOS transistor Q4 are connected to the drain of the MOS transistor Q2, and the drain of the MOS transistor Q4 is connected to the drain of the control IC through the drain of the transistor Q2, and the drain of the gate of the eighteenth pin Q2. Specifically, in the H-bridge topology, when performing the step-down conversion, each cycle mainly includes the following stages: in the inductor charging stage, an MOS (metal oxide semiconductor) tube Q1 and an MOS tube Q2 in the Buck-Boost unit are conducted, an MOS tube Q3 and an MOS tube Q4 are disconnected, and at the moment, a power inductor L4 starts to be charged; in the inductor follow current stage, an MOS (metal oxide semiconductor) tube Q2 and an MOS tube Q3 in the Buck-Boost unit are conducted, the MOS tube Q1 and an MOS tube Q4 are disconnected, and at the moment, the power inductor L4 starts to discharge; through the inductance charging stage and the inductance discharging stage, the Buck-Boost unit can realize voltage reduction conversion.

When performing a boost conversion, each cycle mainly comprises the following phases: in the inductor charging stage, the MOS tube Q1 and the MOS tube Q4 in the Buck-Boost unit are conducted, and the MOS tube Q2 and the MOS tube III are conductedThe MOS tube Q3 is disconnected, and at the moment, the power inductor L4 starts to charge; in the inductor freewheeling stage, an MOS (metal oxide semiconductor) transistor Q2 and an MOS transistor Q3 in the Buck-Boost unit are switched on, an MOS transistor Q1 and an MOS transistor Q4 are switched off, and at the moment, the power inductor L4 starts to discharge; through the inductance charging stage and the inductance discharging stage, the Buck-Boost unit can realize Boost conversion. The Buck-Boost unit can realize the voltage boosting and reducing operation by adjusting the proportion of the charging and discharging time of the inductor. The topology of the H-bridge also has the advantage of a small energy storage inductance, the inductance value of the power inductor L4 being equal to

Further, the inductance value of the power inductor L4 is 2.2 muH, which is only less than 1/10 of the inductance value of the conventional Buck-Boost circuit.

Preferably, the second overcurrent protection unit includes a sampling resistor RS2, the drain of the MOS transistor Q2 and the fifteenth pin CSP2 of the control IC are both connected to one end of the sampling resistor RS2, and the fourteenth pin CSN2 of the control IC, the thirteenth pin OUT of the control IC, and the input end of the second filtering unit are all connected to the other end of the sampling resistor RS 2. Further, the second filtering unit includes a capacitor C24, a capacitor C25, a capacitor C26, a capacitor C27, and a capacitor C28, one end of the capacitor C24, one end of the capacitor C25, one end of the capacitor C26, one end of the capacitor C27, one end of the capacitor C28, the voltage adjusting unit, the fourteenth pin CSN2 of the control IC, and the thirteenth pin OUT of the control IC are all connected to the other end of the sampling resistor RS2, and the other end of the capacitor C24, the other end of the capacitor C25, the other end of the capacitor C26, the other end of the capacitor C27, and the other end of the capacitor C28 are commonly grounded. In this embodiment, the second overcurrent protection unit is connected between the Buck-Boost unit and the second filtering unit, and also has a detection effect on the current, so that quick and reliable short-circuit protection can be realized.

Preferably, the soft start unit includes a resistor R24, specifically, the ninth pin FSW of the control IC is grounded through the resistor R24, in this embodiment, the circuit is protected by selecting the fixed frequency auxiliary oscillator to determine the soft start time through the resistance of the resistor R24, so that a large impact current caused by the charging circuit in the starting process is effectively reduced, the switching device in the H-bridge is protected, and the service life of the backup power charging device is prolonged

Preferably, the boost unit includes a capacitor C15, a capacitor C16, a resistor R17, a resistor R18, and a rectifier bridge D10, specifically, one end of the power inductor L4, the drain of the MOS transistor Q3, and the source of the MOS transistor Q1 are all connected to one end of the capacitor C15, the other end of the power inductor L4, the drain of the MOS transistor Q4, and the source of the MOS transistor Q2 are all connected to one end of the capacitor C16, the other end of the capacitor C15 and one end of the resistor R17 are all connected to a first output end of the rectifier bridge D10, the other end of the capacitor C16 and one end of the resistor R18 are all connected to a second output end of the rectifier bridge D10, the other end of the resistor R17 is connected to a twenty-fourth pin BST1 of the control IC, the other end of the resistor R18 is connected to a nineteenth pin BST2 of the control IC, and an input end of the rectifier bridge D10 is connected to a seventeenth pin VCC of the control IC. In this embodiment, the MOS transistor Q1, the MOS transistor Q2, the MOS transistor Q3, and the MOS transistor Q4 are preferably a vehicle-class MOS transistor NVMFS5C460NL, and the NMOS transistors of this type have different on-internal resistances, and in order to further reduce the conduction loss of the MOS transistor, the VGS voltages of the MOS transistor Q1 and the MOS transistor Q2 are increased by charging the capacitor, when the MOS transistor Q1 is turned off, the capacitor C15 is charged by the power supply voltage VCC, when the MOS transistor Q2 is turned off, the capacitor C16 is charged by the power supply voltage VCC, when the MOS transistor Q1 needs to be turned on, the driving voltage VGS of the MOS transistor Q1 is the voltage on the capacitor C15 plus VCC, and when the MOS transistor Q2 needs to be turned on, the driving voltage VGS of the MOS transistor Q2 is the voltage on the capacitor C16 plus VCC, so as to reduce the conduction loss of the H-bridge charging circuit.

Further, the voltage regulation unit includes a resistor R22, a resistor R28, and a resistor R30, one end of the capacitor C24, one end of the capacitor C25, one end of the capacitor C26, one end of the capacitor C27, and one end of the capacitor C28 are all connected to one end of the resistor R22, one end of the resistor R28 is connected to the other end of the resistor R22, one end of the resistor R30 and the other end of the resistor R28 are all connected to the eighth pin FB of the control IC, and the other end of the resistor R30 is grounded. In this embodiment, the voltage divider circuit formed by the resistor R22, the resistor R28 and the resistor R30 samples the output terminal of the standby power charging device and provides the sampled output voltage to the eighth pin FB of the control IC through a voltage feedback loop to regulate the output voltage.

Example two:

as shown in fig. 2-4, a standby power charging device includes a main circuit and a control circuit, the main circuit includes an EMC unit, a first filtering unit, a Buck-Boost unit, a second filtering unit, a first overcurrent protection unit and a second overcurrent protection unit, the control circuit includes a control IC, a soft start unit, a Boost unit and a voltage regulation unit, an output end of the EMC unit is connected with an input end of the first filtering unit, an output end of the first filtering unit and an input end of the Buck-Boost unit are both connected with the first overcurrent protection unit, an output end of the Buck-Boost unit and an input end of the second filtering unit are both connected with the second overcurrent protection unit, the soft start unit, the voltage regulation unit, the Boost unit, the Buck-Boost unit, the first overcurrent protection unit and the second overcurrent protection unit are all connected with the control IC, and the Buck-Boost unit is connected with the Boost unit. In this embodiment, the first overcurrent protection unit is connected between the first filtering unit and the Buck-Boost unit, so as to detect the current, and realize quick and reliable short-circuit protection, and the second overcurrent protection unit is connected between the Buck-Boost unit and the second filtering unit, so as to detect the current, so as to realize quick and reliable short-circuit protection.

Preferably, the EMC unit is preferably an EMC circuit, which is an electromagnetic compatibility circuit, and an EMC filter is optionally used for protecting a front end from lightning surge. The first filtering unit and the second filtering unit are respectively used as filtering circuits of an input end and an output end of a standby power supply charging device to reduce ripples of the whole circuit, the Buck-Boost unit is used as a topological circuit of a main loop, the first overcurrent protection unit is connected between the first filtering unit and the Buck-Boost unit and has a function of detecting current to realize quick and reliable short-circuit protection, meanwhile, the second overcurrent protection unit is connected between the Buck-Boost unit and the second filtering unit and also has a function of detecting current to realize quick and reliable short-circuit protection, the two overcurrent protection units are independent from each other and cannot influence each other, the control IC is used as a core component of the standby power supply charging device to play a role of controlling charging of energy storage equipment, the soft starting unit is connected with the control IC and can effectively reduce impact current caused by the circuit in the starting process, the impact current is determined by a fixed frequency auxiliary oscillator, in addition, the voltage regulation unit samples output voltage of the second filtering unit and feeds the output voltage back to the control IC, and the Buck-Boost unit is controlled by duty ratio of output PWM in the control IC to regulate output voltage; furthermore, the control IC controls the boosting unit to improve the driving voltage in the Buck-Boost unit, and the Buck-Boost unit is boosted and driven when the driving voltage is insufficient in the Buck-Boost unit.

Specifically, the first filtering unit includes a capacitor C18, a capacitor C19, a capacitor C20, a capacitor C21, a capacitor C22, and a capacitor C23, the output terminal of the EMC unit, one end of the capacitor C18, one end of the capacitor C19, one end of the capacitor C20, one end of the capacitor C21, one end of the capacitor C22, one end of the capacitor C23, the first overcurrent protection unit, and the fourth pin CSP1 of the control IC are all connected to the fifth pin IN of the control IC, and the other end of the capacitor C18, the other end of the capacitor C19, the other end of the capacitor C20, the other end of the capacitor C21, the other end of the capacitor C22, and the other end of the capacitor C23 are grounded IN common. Preferably, the first overcurrent protection unit includes a sampling resistor RS1, the output end of the EMC unit, one end of the capacitor C18, one end of the capacitor C19, one end of the capacitor C20, one end of the capacitor C21, one end of the capacitor C22, one end of the capacitor C23, a fourth pin CSP1 of the control IC, and a fifth pin IN of the control IC are all connected to one end of the resistor RS1, and the input end of the Buck-Boost unit and the third pin CSN1 of the control IC are all connected to the other end of the resistor RS 1. In this embodiment, the Buck-Boost unit may be replaced by a Buck converter, a Buck-Boost converter or a Boost converter, where the Buck-Boost converter may Boost or Buck voltage by using the same circuit according to application, and the number of capacitors connected in series may be selected by a super capacitor bank in the standby power supply system of the vehicle-mounted LCD player controller according to specific requirements of a project, so that the Buck-Boost with adjustable output voltage is selected as a preferred option, and a topology with an H bridge is adopted in the Buck-Boost circuit as a preferred option, and the topology with the H bridge has advantages that a series of conventional Buck-Boost circuits do not have, such as frequency multiplication, small energy storage inductance, same polarity of input and output voltages, wide input and output voltages, and the like. Specifically, the Buck-Boost unit includes a MOS transistor Q1, a MOS transistor Q2, a MOS transistor Q3, a MOS transistor Q4, a power inductor L4, a resistor R13, a resistor R14, a resistor R15, and a resistor 16, the other ends of a third pin CSN1 and a resistor RS1 of the control IC are connected to a drain of the MOS transistor Q1, a gate of the MOS transistor Q1 is connected to a twenty-third pin DH1 of the control IC through the resistor R14, one end of the Boost unit, the power inductor L4, and a drain of the MOS transistor Q3 are connected to a source of the MOS transistor Q1, the gate of the MOS transistor Q3 is connected to a first pin DL1 of the control IC through the resistor R16, a source of the MOS transistor Q3 is grounded, the fifteenth pin CSP2 of the second overcurrent protection unit and the control IC are connected to a drain of the MOS transistor Q2, the gate of the MOS transistor Q2 is connected to a twenty-th pin DH2 of the control IC through the resistor R13, the other end of the power inductor L4, the Boost unit, and the source of the MOS transistor Q4 are connected to a drain of the MOS transistor Q2, and a drain of the MOS transistor Q2 of the control IC are connected to a drain of the eighteenth pin Q4, and a drain of the MOS transistor Q2, and a drain of the control IC are connected to a drain of the control IC through the resistor R15. Specifically, in the H-bridge topology, when performing the step-down conversion, each cycle mainly includes the following stages: in the inductor charging stage, an MOS (metal oxide semiconductor) tube Q1 and an MOS tube Q2 in the Buck-Boost unit are conducted, an MOS tube Q3 and an MOS tube Q4 are disconnected, and at the moment, a power inductor L4 starts to be charged; in the inductor follow current stage, an MOS (metal oxide semiconductor) tube Q2 and an MOS tube Q3 in the Buck-Boost unit are conducted, the MOS tube Q1 and an MOS tube Q4 are disconnected, and at the moment, the power inductor L4 starts to discharge; through the inductance charging stage and the inductance discharging stage, the Buck-Boost unit can realize voltage reduction conversion.

When performing boost conversion, each cycle mainly includes the following stages: in the inductor charging stage, an MOS (metal oxide semiconductor) tube Q1 and an MOS tube Q4 in the Buck-Boost unit are conducted, an MOS tube Q2 and a three-MOS tube Q3 are disconnected, and at the moment, the power inductor L4 starts to be charged; in the inductor follow current stage, an MOS (metal oxide semiconductor) tube Q2 and an MOS tube Q3 in the Buck-Boost unit are conducted, the MOS tube Q1 and an MOS tube Q4 are disconnected, and at the moment, the power inductor L4 starts to discharge; through the inductance charging stage and the inductance discharging stage, the Buck-Boost unit can realize Boost conversion. The Buck-Boost unit can realize the voltage boosting and reducing operation of the voltage by adjusting the proportion of the charging time and the discharging time of the inductor. The topology of the H-bridge also has the advantage of a small energy storage inductance, the inductance value of the power inductor L4 being equal to

Furthermore, the inductance value of the power inductor L4 is 2.2 muH, which is only less than 1/10 of the inductance value of the conventional Buck-Boost circuit.

Preferably, the second overcurrent protection unit includes a sampling resistor RS2, the drain of the MOS transistor Q2 and the fifteenth pin CSP2 of the control IC are both connected to one end of the sampling resistor RS2, and the fourteenth pin CSN2 of the control IC, the thirteenth pin OUT of the control IC, and the input end of the second filtering unit are all connected to the other end of the sampling resistor RS 2. Further, the second filtering unit includes a capacitor C24, a capacitor C25, a capacitor C26, a capacitor C27, and a capacitor C28, one end of the capacitor C24, one end of the capacitor C25, one end of the capacitor C26, one end of the capacitor C27, one end of the capacitor C28, the voltage adjusting unit, the fourteenth pin CSN2 of the control IC, and the thirteenth pin OUT of the control IC are all connected to the other end of the sampling resistor RS2, and the other end of the capacitor C24, the other end of the capacitor C25, the other end of the capacitor C26, the other end of the capacitor C27, and the other end of the capacitor C28 are commonly grounded. In this embodiment, the second overcurrent protection unit is connected between the Buck-Boost unit and the second filtering unit, and also has a detection function on the current, so that quick and reliable short-circuit protection can be realized.

Preferably, the boost unit includes a capacitor C15, a capacitor C16, a resistor R17, a resistor R18, and a rectifier bridge D10, specifically, one end of the power inductor L4, a drain of the MOS transistor Q3, and a source of the MOS transistor Q1 are all connected to one end of the capacitor C15, the other end of the power inductor L4, a drain of the MOS transistor Q4, and a source of the MOS transistor Q2 are all connected to one end of the capacitor C16, the other end of the capacitor C15, and one end of the resistor R17 are all connected to a first output end of the rectifier bridge D10, the other end of the capacitor C16, and one end of the resistor R18 are all connected to a second output end of the rectifier bridge D10, the other end of the resistor R17 is connected to a twenty-fourth pin BST1 of the control IC, the other end of the resistor R18 is connected to a nineteenth pin BST2 of the control IC, and an input end of the rectifier bridge D10 is connected to a seventeenth pin VCC of the control IC. In this embodiment, the MOS transistor Q1, the MOS transistor Q2, the MOS transistor Q3, and the MOS transistor Q4 are preferably a vehicle-class MOS transistor NVMFS5C460NL, and the NMOS transistors of this type have different on-internal resistances, and in order to further reduce the conduction loss of the MOS transistor, the VGS voltages of the MOS transistor Q1 and the MOS transistor Q2 are increased by charging the capacitor, when the MOS transistor Q1 is turned off, the capacitor C15 is charged by the power supply voltage VCC, when the MOS transistor Q2 is turned off, the capacitor C16 is charged by the power supply voltage VCC, when the MOS transistor Q1 needs to be turned on, the driving voltage VGS of the MOS transistor Q1 is the voltage on the capacitor C15 plus VCC, and when the MOS transistor Q2 needs to be turned on, the driving voltage VGS of the MOS transistor Q2 is the voltage on the capacitor C16 plus VCC, so as to reduce the conduction loss of the H-bridge charging circuit.

The LED driving circuit further comprises a current limiting unit, the current limiting unit comprises a sampling resistor RS3, a resistor R5, a sliding rheostat R6, a resistor R7, a resistor R8, a capacitor C6, an LED1 and an operational amplifier U4, one end of a capacitor C24, one end of a capacitor C25, one end of a capacitor C26, one end of a capacitor C27, one end of a capacitor C28 and one end of a resistor R22 are connected with one end of the sampling resistor RS3, the other end of the sampling resistor RS3 is connected with a forward input end of the operational amplifier U4, one end of the resistor R5 is connected with one end of the resistor R7, the other end of the resistor R5 is connected with one end of the sliding rheostat R6, the other end of the resistor R7, one end of the resistor R8, one end of the capacitor C6 and a sliding end of the sliding rheostat R6 are connected with a reverse input end of the operational amplifier U4, the other end of the resistor R8 and the other end of the sliding rheostat R6 are grounded, the other end of the capacitor C6 and a positive electrode of the LED1 are connected with an output end of the operational amplifier U4, and a negative electrode of the LED control pin of the LED control IC 1 are connected with a negative electrode of the operational amplifier U4. Specifically, the control IC controls the output current to be 5A at most, but according to actual requirements of different super capacitor banks, the charging current needs to be limited to 3A, in this embodiment, by adding the sampling resistor RS3 to the output end of the second filtering unit, and by using the voltage dividing circuit formed by the resistor R5, the resistor R6 and the sampling resistor RS3, the output of the voltage dividing circuit is compared and output to the feedback end (eighth pin FB) of the control IC through the operational amplifier U4, so that the charging current is limited to 3A.

Example three:

as shown in fig. 1 to 6, a standby power supply system for a vehicle-mounted LCD playback controller includes a redundancy switching module, a DC/DC charging module, and a super capacitor bank module, where the DC/DC charging module includes a standby power charging device according to any one of the first and second embodiments, an output end of the redundancy switching module and an output end of the super capacitor bank module are both connected to an input end of the vehicle-mounted LCD playback controller, and an input end of the super capacitor bank module is connected to an output end of the redundancy switching module through the standby power charging device. In this embodiment, carry out the redundant power supply to on-vehicle LCD play controller through redundant switching module, simultaneously charge to super capacitor group module through stand-by power supply charging device, guarantee on-vehicle LCD play controller can start and super capacitor group module in the short time in time carries out the energy storage, make super capacitor group module carry out the reserve as stand-by power supply, when the external power supply disconnection, super capacitor group module provides the time delay power supply of certain duration to on-vehicle LCD play controller, on-vehicle LCD play controller time delay shutdown when realizing the external power supply outage.

Further, the redundancy switching module comprises a diode D1 and a diode D2, the anode of the diode D1 is connected with a first power supply, the anode of the diode D2 is connected with a second power supply, the anode of the input end of the standby power supply charging device, the anode of the input end of the vehicle-mounted LCD playing controller and the cathode of the diode D2 are connected with the cathode of the diode D1, and the cathode of the second power supply, the cathode of the input end of the standby power supply charging device and the cathode of the input end of the vehicle-mounted LCD playing controller are connected with the cathode of the first power supply. In this embodiment, a first power supply and a second power supply are used to supply power in combination with the redundant power supply requirement of the system, and a diode D1 and a diode D2 are respectively disposed on the first power supply and the second power supply to prevent the dual power supply output ends from flowing backward to each other to cause power supply damage. Furthermore, the first power supply and the second power supply can be selected from power supply equipment which meets the requirements of certification of a BS EN/EN50155 railway system and certification of a BS EN/EN45545-2 railway system and vehicle-mounted scene application, preferably, the bright weft power supply RSD-100D-12, wherein the maximum current output by the bright weft power supply RSD-100D-12 is 8.4A, in order to ensure that when the vehicle-mounted LCD player controller is powered on for the first time or the super capacitor bank is charged, the player controller main control board connected to the rear end of the standby power supply in the vehicle-mounted LCD player controller can be normally powered on, the charging current of the standby power supply charging device is limited to 5A to charge the super capacitor bank, and meanwhile, redundant current can enable the vehicle-mounted LCD player controller main control board to be normally powered on.

Preferably, the device also comprises a secondary battery group, the secondary battery group comprises a diode D3, a diode D4 and a diode D5, the cathode of the diode D1 and the cathode of the diode D2 are both connected with the anode of the diode D3, the output end of the super capacitor group module is connected with the anode of the diode D4, the cathode of the diode D3 and the cathode of the diode D4 are both connected with the input end of the vehicle-mounted LCD playing controller, the output end of the standby power supply charging device is connected with the anode of the diode D5, and the cathode of the diode D5 is connected with the input end of the super capacitor group module. In the embodiment, the diode D3, the diode D4 and the diode D5 distributed in the power supply circuit play a role of directing the current direction through the unidirectional conductive characteristic of the diode, and in addition, due to the fact that the diode is a passive device, a plurality of switches or relays and other control devices do not need to be added in the whole circuit, and the design of the whole system is further simplified.

Further, super capacitor group module includes the super capacitor group that a plurality of super capacitors establish ties and form, is connected with the equalizing unit on each super capacitor, connect ADC voltage sampling unit between on-vehicle LCD broadcast controller and the super capacitor group, the input of super capacitor group is connected with stand-by power charging device's output, the output of redundancy switch module and on-vehicle LCD broadcast controller's input all are connected with the output of super capacitor group. In the embodiment, a plurality of super capacitors are connected in series to form a super capacitor bank, the input end of the super capacitor bank is connected with the output end of the standby power charging device, the main control board of the vehicle-mounted LCD playing controller and the output end of at least one bright weft power supply RSD-100D-12 are both connected with the super capacitor bank, and the super capacitor bank is connected with the vehicle-mounted LCD playing controller through the ADC voltage sampling unit. In the present embodiment, it is preferred that,the super capacitor group is selected as a standby power supply of the vehicle-mounted LCD play controller, the super capacitor is used as a new passive device, the super capacitor is arranged between a battery and a common capacitor, the super capacitor has the characteristics of high-current quick charge and discharge of the capacitor and energy storage of the battery, has the characteristics of long repeated service life and wide working temperature range (40-70 ℃), solves the problem that the conventional lithium battery standby power supply is difficult to meet the service temperature environment of a system, and provides the delayed power supply capacity of more than 30S when the external power supply of the vehicle-mounted LCD play controller is disconnected; according to a calculation formula of the capacity of the super capacitor: c = (vwok + Vmin) × I × (vwok 2-Vmin 2), vwok (V): normal operating voltage, vmin (V): cutting off the working voltage; t(s): required duration in the circuit, I (a): load current, if Vword =13V, vmin =8V, t =30s, I =2A, then C = [ (13 + 8) × 2 × 30]/(13 ² -8 ² ) =12F, preferably, the super capacitor bank adopts 6 super capacitors with 20F capacity connected in series to form 120F capacity; furthermore, each supercapacitor monomer structure in the supercapacitor group is connected with a voltage balancing unit in a matching mode, the balancing unit comprises a supercapacitor management chip and a voltage balancing circuit, the supercapacitor management chip adopts a high-precision internal voltage reference, the protection voltage precision is guaranteed to be within 1%, a built-in power tube can provide large-current discharge capacity, and 700mA current discharge capacity can be provided under the condition that no external current expansion tube exists, so that the problem that the wood barrel effect among the supercapacitors is limited by the worst-property monomer is solved through the balancing unit, and parameters such as equivalent capacitance values and equivalent series resistance values among the supercapacitor monomers are obviously inconsistent due to the fact that the wood barrel effect is limited by factors such as materials and manufacturing levels among the supercapacitors.

Preferably, the balancing unit includes a super capacitor management chip U1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, an MOS transistor Q1 and a light emitting diode LED1, the anode of the super capacitor, one end of the resistor R1, one end of the resistor R2, one end of the resistor R3, one end of the resistor R4 and one end of the resistor R5 are all connected to a first pin VDD of the super capacitor management chip U1, the cathode of the super capacitor and the cathode of the light emitting diode LED1 are all connected to a second pin GND of the super capacitor management chip U1, the other end of the resistor R1 is connected to a third pin SEL of the super capacitor management chip U1, one end of the resistor R6 is connected to a fourth pin LED of the super capacitor management chip U1, one end of the resistor R7 and the gate of the MOS transistor Q1 are all connected to a fifth pin ioi of the super capacitor management chip U1, the other end of the resistor R2, the other end of the resistor R3, the other end of the resistor R4 and the other end of the resistor R5 are all connected to a drain of the MOS transistor Q1 and a source of the resistor R1, and the source of the super capacitor management chip R1 are all connected to a drain of the light emitting diode Q1. In this embodiment, the super capacitor management chip U1 adopts a high-precision voltage reference to ensure that the protection voltage precision is within 1%, the built-in power tube can provide a large current discharge capability, and can provide a current discharge capability of 700mA without an external current spreading tube, further, an MOS tube Q1 is further provided, when a third pin SEL of the super capacitor management chip U1 is pulled up, the charging voltage of the single super capacitor is set to be 2.65V, and when the single voltage of the super capacitor exceeds 2.65V during charging, the fifth pin IOUT of the super capacitor management chip U1 outputs a current of 0.7A to a resistor R7, preferably, the MOS tube Q1 is connected behind the fifth pin IOUT of the super capacitor management chip U1 to further increase the discharge current to 7A, when overvoltage occurs, the MOS tube Q1 is turned on, and the two ends of the super capacitor C1 discharge through a resistor R2, a resistor R3, a resistor R4 and a resistor R5 connected in parallel, so as to meet the protection requirement of a high-capacity faraday capacitor module, such as 120F.

In this embodiment, still include the MCU module, the MCU module includes switch element, first voltage sampling unit, second voltage sampling unit, communication unit and MCU unit, diode D4's negative pole passes through the switch element and links to each other with on-vehicle LCD play controller's input, diode D1's negative pole and diode D3's positive pole all are connected with the sense terminal of first voltage sampling unit, the sense terminal and the super capacitor group module of second voltage sampling unit are connected, the output of first voltage sampling unit, the output and the switch element of second voltage sampling unit all are connected with the MCU unit, the communication end of MCU unit passes through the communication unit and is connected with on-vehicle LCD play controller. Specifically, the MCU unit is powered by a power supply or a standby power supply charging device of the MCU unit, the MCU unit serves as a processor of the standby power supply device of the vehicle-mounted LCD play controller and is responsible for judging whether the outside of the vehicle-mounted LCD play controller is powered off or not, so that the switch unit is driven to be disconnected or closed, when the outside is powered off, the switch unit is driven to be closed, the super capacitor bank provides the standby power supply for the vehicle-mounted LCD play controller, when the outside is normally powered off, the switch unit is driven to be disconnected, the redundancy switching module supplies power to the vehicle-mounted LCD play controller, and preferably, the MCU unit also monitors the running state of the super capacitor bank and transmits running data of the super capacitor bank to the vehicle-mounted LCD play controller through the communication unit. The first voltage sampling unit is used for sampling the voltage of a connecting point of the diode D1 and the diode D3 to the ground to judge whether the outside of the vehicle-mounted LCD playing controller system is powered off or not, the second voltage sampling unit is used for collecting the voltage of the super capacitor bank to monitor the running state information of the series super capacitor bank, and the communication unit preferably selects RS232 communication equipment and is used for serial port data communication with a main control board of the vehicle-mounted LCD playing controller.

Preferably, the buffer unit is further connected with the anode of the diode D4, the cathode of the diode D5 and the super capacitor bank module, and the buffer unit is a wound inductor or a metal aluminum shell resistor, preferably a 100 muH/30A/1.2 mm double-wire wound inductor or a 50W/4 omega resistor. So as to restrain the current sudden change in the charging and discharging process and reduce the power supply ripple.

In this embodiment, when the vehicle-mounted LCD playback controller is first powered on, the redundancy switching module charges the super capacitor bank through the DC/DC charging module and through the diode D5 and the buffer unit, wherein the buffer unit suppresses current sudden change and reduces power supply ripple during charging, and the vehicle-mounted LCD playback controller is normally powered on to operate the entire system; in the charging process, the MCU module monitors the running state of the series super capacitor bank in real time, and performs voltage equalization on the super capacitors through the equalization unit, so that the voltage equalization problem of each super capacitor in the series super capacitor bank is effectively solved, the influence on the performance and the service life of the standby power supply due to individual difference is avoided, and the maintenance cost is reduced; when an external power supply is powered off, the first voltage sampling unit detects that the space between the vehicle-mounted LCD playing controller and the redundancy switching module is disconnected, the MCU unit block drives the switch unit to be closed, the super capacitor group starts to supply power to the vehicle-mounted LCD playing controller through the buffer unit and the diode D4, the buffer unit inhibits the current mutation and reduces the power ripple in the discharging process, and meanwhile, the diode D3 and the diode D5 prevent the super capacitor group from unnecessarily discharging the standby power charging device and the redundancy switching module at the front end, so that the energy-saving purpose is achieved, and in the running process of the standby power system of the vehicle-mounted LCD playing controller, the standby power system of the vehicle-mounted LCD playing controller works independently, and the whole system design is further independent.

Various other modifications and changes may be made by those skilled in the art based on the above-described technical solutions and concepts, and all such modifications and changes should fall within the scope of the claims of the present invention.

Claims

1. A stand-by power supply charging device characterized in that: the main circuit comprises an EMC unit, a first filtering unit, a Buck-Boost unit, a second filtering unit, a first overcurrent protection unit and a second overcurrent protection unit, the control circuit comprises a control IC, a soft start unit, a Boost unit and a voltage regulation unit, the output end of the EMC unit is connected with the input end of the first filtering unit, the output end of the first filtering unit and the input end of the Buck-Boost unit are connected with the first overcurrent protection unit, the output end of the Buck-Boost unit and the input end of the second filtering unit are connected with the second overcurrent protection unit, the soft start unit, the voltage regulation unit, the Boost unit, the Buck-Boost unit, the first overcurrent protection unit and the second overcurrent protection unit are connected with the control IC, and the Buck-Boost unit is connected with the Boost unit.

2. The backup power charging apparatus according to claim 1, wherein: the first filtering unit comprises a capacitor C18, a capacitor C19, a capacitor C20, a capacitor C21, a capacitor C22 and a capacitor C23, the output end of the EMC unit, one end of the capacitor C18, one end of the capacitor C19, one end of the capacitor C20, one end of the capacitor C21, one end of the capacitor C22, one end of the capacitor C23, the first overcurrent protection unit and the fourth pin CSP1 of the control IC are all connected with the fifth pin IN of the control IC, and the other end of the capacitor C18, the other end of the capacitor C19, the other end of the capacitor C20, the other end of the capacitor C21, the other end of the capacitor C22 and the other end of the capacitor C23 are grounded IN common.

3. The backup power charging apparatus according to claim 2, wherein: the first overcurrent protection unit comprises a sampling resistor RS1, the output end of the EMC unit, one end of a capacitor C18, one end of a capacitor C19, one end of a capacitor C20, one end of a capacitor C21, one end of a capacitor C22, one end of a capacitor C23, a fourth pin CSP1 of the control IC and a fifth pin IN of the control IC are connected with one end of the resistor RS1, and the input end of the Buck-Boost unit and a third pin CSN1 of the control IC are connected with the other end of the resistor RS 1.

4. A backup power charging apparatus according to claim 3, wherein: the Buck-Boost unit comprises an MOS tube Q1, an MOS tube Q2, an MOS tube Q3, an MOS tube Q4, a power inductor L4, a resistor R13, a resistor R14, a resistor R15 and a resistor 16, the other ends of a third pin CSN1 and a resistor RS1 of the control IC are connected with the drain electrode of the MOS tube Q1, the grid electrode of the MOS tube Q1 is connected with a twenty-third pin DH1 of the control IC through the resistor R14, one ends of the Boost unit, the power inductor L4 and the drain electrode of the MOS tube Q3 are connected with the source electrode of the MOS tube Q1, the grid electrode of the MOS tube Q3 is connected with a first pin DL1 of the control IC through the resistor R16, the source electrode of the MOS tube Q3 is grounded, the fifteenth pin 2 of the second overcurrent protection unit and the CSP control IC are connected with the drain electrode of the MOS tube Q2, the grid electrode of the MOS tube Q2 is connected with a twenty-th pin DH2 of the control IC through the resistor R13, the other end of the power inductor L4, the Boost unit and the MOS tube Q4 are connected with the drain electrode of the MOS tube Q2, and the drain electrode of the MOS tube Q4 are connected with the drain electrode of the MOS tube Q2, and the drain electrode of the MOS tube Q2 of the MOS tube Q4 are connected with the drain electrode of the MOS tube Q2.

5. The backup power charging apparatus according to claim 4, wherein: the second overcurrent protection unit comprises a sampling resistor RS2, the drain electrode of the MOS tube Q2 and a fifteenth pin CSP2 of the control IC are connected with one end of the sampling resistor RS2, and a fourteenth pin CSN2 of the control IC, a thirteenth pin OUT of the control IC and the input end of the second filtering unit are connected with the other end of the sampling resistor RS 2.

6. The backup power charging apparatus according to claim 5, wherein: the second filtering unit comprises a capacitor C24, a capacitor C25, a capacitor C26, a capacitor C27 and a capacitor C28, one end of the capacitor C24, one end of the capacitor C25, one end of the capacitor C26, one end of the capacitor C27, one end of the capacitor C28, a voltage adjusting unit, a fourteenth pin CSN2 of the control IC and a thirteenth pin OUT of the control IC are all connected with the other end of the sampling resistor RS2, and the other end of the capacitor C24, the other end of the capacitor C25, the other end of the capacitor C26, the other end of the capacitor C27 and the other end of the capacitor C28 are grounded in common.

7. The backup power charging apparatus according to claim 6, wherein: the soft start unit comprises a resistor R24, the boost unit comprises a capacitor C15, a capacitor C16, a resistor R17, a resistor R18 and a rectifier bridge D10, the voltage regulation unit comprises a resistor R22, a resistor R28 and a resistor R30, a ninth pin FSW of the control IC is grounded through the resistor R24, one end of a power inductor L4, a drain electrode of an MOS transistor Q3 and a source electrode of the MOS transistor Q1 are all connected with one end of the capacitor C15, the other end of the power inductor L4, the drain electrode of the MOS transistor Q4 and the source electrode of the MOS transistor Q2 are all connected with one end of the capacitor C16, the other end of the capacitor C15 and one end of the resistor R17 are all connected with a first output end of the rectifier bridge D10, the other end of the capacitor C16 and one end of the resistor R18 are all connected with a second output end of the rectifier bridge D10, the other end of the resistor R17 is connected with a twenty-fourth pin BST1 of the control IC, the other end of the resistor R18 is connected with a nineteenth output end of the control IC 2, the other end of the rectifier bridge D10 is connected with a seventeenth pin of the resistor R24 and one end of the resistor R30, one end of the resistor R22 are connected with one end of the control IC 22 and one end of the resistor R30 are all connected with one end of the resistor R26.

8. The backup power charging apparatus according to claim 7, wherein: the LED driving circuit further comprises a current limiting unit, the current limiting unit comprises a sampling resistor RS3, a resistor R5, a sliding rheostat R6, a resistor R7, a resistor R8, a capacitor C6, an LED1 and an operational amplifier U4, one end of a capacitor C24, one end of a capacitor C25, one end of a capacitor C26, one end of a capacitor C27, one end of a capacitor C28 and one end of a resistor R22 are all connected with one end of the sampling resistor RS3, the other end of the sampling resistor RS3 is connected with a forward input end of the operational amplifier U4, one end of the resistor R5 is connected with one end of the resistor R7, the other end of the resistor R5 is connected with one end of the sliding rheostat FB R6, the other end of the resistor R7, one end of the resistor R8, one end of the capacitor C6 and a sliding end of the sliding rheostat R6 are all connected with a reverse input end of the operational amplifier U4, the other end of the resistor R8 and the other end of the sliding rheostat R6 are grounded, the other end of the capacitor C6 and an anode of the LED1 are all connected with an output end of the operational amplifier U4, and a cathode of the LED1 is connected with a control pin of the LED control IC 1.

9. The utility model provides a vehicle-mounted LCD play controller stand-by power supply system, includes redundancy switch module, DC/DC module and super capacitor group module of charging, its characterized in that: the DC/DC charging module comprises the standby power supply charging device as claimed in any one of claims 1 to 8, the output end of the redundancy switching module and the output end of the super capacitor bank module are both connected with the input end of the vehicle-mounted LCD playing controller, and the input end of the super capacitor bank module is connected with the output end of the redundancy switching module through the standby power supply charging device.