Low-power DC-DC circuit

Abstract

The present invention aims to provide a low-power DC-DC circuit, which has a simple structure, can completely turn off an operation power supply of the entire circuit when in a non-operating state, and can effectively prolong the storage time of a battery. The circuit provided in the present invention comprises a DC-DC circuit main body (1) consisting of a DC-DC chip (U1) and a peripheral circuit thereof, wherein a VIN pin of the DC-DC chip (U1) is connected to a battery (BAT), and an output pin of the DC-DC chip (U1) is connected to positive and negative electrodes of a load (Load). In the circuit, an on-off switch (2) is further provided on the VIN pin of the DC-DC chip (U1), and the on-off switch (2) controls, on the basis of the requirements of the load, the connection / disconnection between the battery (BAT) and the DC-DC circuit main body (1) by means of a connected controller (MCU). The present invention is applied to the technical field of power supplies.

Description

Low-power DC-DC circuit TECHNICAL FIELD

[0001] The present application relates to the field of power supply technology, in particular to a low-power DC-DC circuit. BACKGROUND

[0002] The current product power supply circuit uses the EN-PIN of the DC-DC controller itself to turn off or enable, as shown in FIG. 1, the battery supplies power, and whether the circuit outputs power to the load is controlled by the DC-DC chip U2. However, even if the EN in the circuit turns off the DC-DC work, since the battery and the entire circuit still exist physical conduction, the entire circuit still exists power consumption. This power consumption will continuously consume energy, reduce the storage time of the battery, increase the useless energy consumption of the circuit, and cause the product in the battery field to be charged every period of time, which causes trouble to the user. In the field of commercial power, energy is continuously wasted.

[0003] Therefore, it is urgent to design a DC-DC circuit which can completely turn off the working power supply of the entire circuit in a non-working state to ensure the service life of the battery. SUMMARY

[0004] The technical problem to be solved by the present application is to overcome the shortcomings of the prior art, and to provide a low-power DC-DC circuit which has a simple structure, can completely turn off the working power supply of the entire circuit in a non-working state, and can effectively prolong the storage time of the battery.

[0005] The technical solution adopted by the present application is that the circuit includes a DC-DC circuit main body composed of a DC-DC chip and its peripheral circuit, the VIN pin of the DC-DC chip is connected with a battery, the output pin of the DC-DC chip is connected with the positive and negative electrodes of a load, and a on-off switch is further arranged on the VIN pin of the DC-DC chip, the on-off switch is controlled by a connected controller to control the on-off between the battery and the DC-DC circuit main body according to the demand of the load.

[0006] Here, the on-off switch is further arranged on the VIN pin of the DC-DC chip, the on-off switch is controlled by a connected controller to control the on-off between the battery and the DC-DC circuit main body according to the demand of the load, in the state of not needing power supply, the controller sends an off signal to the on-off switch, the on-off switch turns off the working power supply of the entire circuit, and the purpose of the DC-DC circuit completely without power consumption is achieved; thereby the working power supply of the entire circuit can be completely turned off in a non-working state, the storage time of the battery can be effectively prolonged, the circuit structure is simple, and the realization is convenient. The battery-powered product can effectively save energy, reduce power consumption, and realize more environmentally friendly application of the battery.

[0007] Further, the on-off switch is a first MOS tube, and the gate of the first MOS tube is connected with the IO port of the controller through a second MOS tube. Here, the static switch characteristic of the MOS tube is utilized, and the on-off between the battery and the main body of the DC-DC circuit is realized by sending signals by the controller, so as to ensure low energy consumption of the circuit.

[0008] Still further, a conduction connection is further arranged between the battery and the load. Thus, when the DC-DC circuit is not needed to control the output, the conduction connection is directly used to realize the output of the battery energy, so as to facilitate the selection of various applications.

[0009] In addition, the controller is a single-chip microcomputer. Here, the single-chip microcomputer is used to send signals to the on-off switch, so as to ensure the stability and reliability of the circuit.

[0010] In addition, the battery is a rechargeable battery. This is conducive to the reuse of the battery, and realizes the environmental protection application. BRIEF DESCRIPTION OF DRAWINGS

[0011] Fig. 1 is a principle block diagram of the product DC-DC circuit of the prior art;

[0012] Fig. 2 is a principle block diagram of the circuit of the present application;

[0013] Fig. 3 is a principle diagram of the circuit of the present application. DETAILED DESCRIPTION

[0014] As shown in Figs. 2 and 3, the present application comprises a DC-DC circuit main body 1 composed of a DC-DC chip U1 and its peripheral circuit, the VIN pin of the DC-DC chip U1 is connected with a battery BAT, and the output pin of the DC-DC chip U1 is connected with the positive and negative electrodes of a load Load. The circuit further comprises an on-off switch 2 arranged on the VIN pin of the DC-DC chip U1, and the on-off switch 2 is controlled by a connected controller MCU according to the demand of the load, so as to control the on-off between the battery BAT and the DC-DC circuit main body 1.

[0015] Specifically, the on-off switch 2 is a first MOS tube Q1, and the gate of the first MOS tube Q1 is connected with the IO port of the controller MCU through a second MOS tube Q2. Here, the second MOS tube effectively protects the MCU. A conduction connection is further arranged between the battery BAT and the load Load. The controller MCU is a single-chip microcomputer. The battery BAT is a rechargeable battery.

[0016] In the DC-DC chip U1, the VIN pin is a power supply pin, the EN_UVLO pin is an enable pin, the RT and SS / TRK pins are frequency modulation pins, the SYNCIN and VCC pins are compensation pins and reference voltage pins, the COMP pin is a compensation pin for compensating when the power supply is unstable or the device has a tolerance, the FB / SW is a voltage regulation pin, the third MOS tube Q3 and the fourth MOS tube Q4 are used for boosting or bucking the output positive and negative electrodes, the HO, BST, ILIM, and LO pins are used for controlling the working state of the third MOS tube Q3 and the fourth MOS tube Q4, and the AGND / PGND is a ground.

[0017] In the present application, after the DC-DC circuit is connected to the battery BAT, the DC-DC chip U1 continuously consumes the power of the battery BAT, a first MOS tube Q1 is added as a on-off switch on the power supply pin of the DC-DC chip U1, when the product is not used, the working power supply of the whole circuit is controlled by the IO port of the controller MCU to achieve the purpose that the DC-DC circuit has no power consumption.

[0018] Finally, it should be emphasized that the above description is only the preferred embodiment of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A low-power DC-DC circuit, comprising a DC-DC circuit main body (1) composed of a DC-DC chip (U1) and its peripheral circuit, a VIN pin of the DC-DC chip (U1) being connected with a battery (BAT), and output pins of the DC-DC chip (U1) being connected with positive and negative poles of a load (Load), characterized in that, The circuit is further provided with a on-off switch (2) on the VIN pin of the DC-DC chip (U1), the on-off switch (2) is controlled by the connected controller (MCU) to control the on-off between the battery (BAT) and the DC-DC circuit body (1) according to the requirement of the load.

2. A low power DC-DC circuit according to claim 1, characterized in that, The on-off switch (2) is a first MOS tube (Q1), the gate of the first MOS tube (Q1) is connected with the IO port of the controller (MCU) through a second MOS tube (Q2).

3. A low power DC-DC circuit according to claim 1, characterized in that, A conducting connection is further provided between the battery (BAT) and the load (Load).

4. A low power DC-DC circuit according to claim 1, characterized in that, The controller (MCU) is a single-chip microcomputer.

5. A low power DC-DC circuit according to claim 1, characterized in that, The battery (BAT) is a rechargeable battery.

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