CN104062591B - A kind of battery low-voltage warning circuit - Google Patents

Abstract

The invention discloses a battery low voltage alarm circuit, comprising: an amplifier circuit, a charging and discharging circuit and a light emitting diode, wherein: the amplifier circuit is connected with the battery, and is used for when the battery voltage reaches a preset low voltage threshold , the voltage of the battery is obtained, and the obtained voltage is amplified and output; the charging and discharging circuit is respectively connected with the amplifying circuit and the light-emitting diode, and is used to charge alternately according to the voltage output by the amplifying circuit and discharge, so that the light-emitting diodes alternately appear on and off; The circuit can achieve the effect of battery low voltage alarm through the flashing of the light emitting diode, and then remind the user to charge or replace the battery in time.

Description

A battery low voltage alarm circuit

technical field

The invention relates to the field of electronics, in particular to a battery low voltage alarm circuit.

Background technique

At present, there are many applications of batteries, and the protection of batteries is also placed in front of the users. The rational application of batteries with the maximum life and maximum performance is the goal pursued by battery researchers. In particular, how to protect the minimum discharge voltage of batteries , so as to protect the battery in time is the focus of current research.

Contents of the invention

The technical problem to be solved by the present invention is to provide a battery low voltage warning circuit, which can prompt when the battery voltage is too low.

In order to solve the above technical problems, the battery low voltage alarm circuit provided by the embodiment of the present invention may include: an amplifier circuit, a charging and discharging circuit, and a light emitting diode, wherein:

The amplifying circuit is connected to the battery, and is used for obtaining the voltage of the battery when the voltage of the battery reaches a preset low voltage threshold, and amplifying and outputting the obtained voltage;

The charge-discharge circuit is respectively connected to the amplifier circuit and the light-emitting diode, and is used to alternately charge and discharge according to the voltage output by the amplifier circuit, so that the light-emitting diodes alternately have a flickering effect of turning on and off ;

The light emitting diodes are respectively connected between the anode of the battery and the charging and discharging circuit.

In some feasible implementation manners, the amplifying circuit includes a resistor R1, an adjustable resistor VR1, a transistor Q1, and a transistor Q2, wherein:

The resistor R1 and the adjustable resistor VR1 are connected in series between the positive and negative electrodes of the battery;

The base of the triode Q1 is connected to the adjustable terminal of the adjustable resistor VR1, the emitters of the triode Q1 and the triode Q2 are connected to the negative pole of the battery, and the collector of the triode Q1 is connected to the negative pole of the battery. The base of the triode Q2 is connected, and the collector of the triode Q2 is connected to the positive pole of the battery.

In some feasible implementation manners, the amplifying circuit further includes a resistor R2, a resistor R3, and a resistor R4, wherein:

The resistor R2 is connected between the positive pole of the battery and the collector of the triode Q1;

The resistor R3 is connected between the positive pole of the battery and the collector of the triode Q2;

The resistor R4 is connected between the emitters of the triode Q1 and the triode Q2 and the negative pole of the battery.

In some feasible implementation manners, the charging and discharging circuit includes a transistor Q3, a capacitor C1, a transistor Q4, and a capacitor C2, wherein:

The base of the transistor Q3 and the cathode of the capacitor C1 are connected to the collector of the transistor Q2;

The emitter of the triode, the positive pole of the capacitor C1, the positive pole of the capacitor C2, and the collector of the triode Q4 are connected to the positive pole of the battery;

The base of the triode Q4 is connected to the collector of the triode Q3, and the emitter of the triode Q4 is connected to the negative pole of the battery;

The cathode of the capacitor C2 is connected to the LED.

In some feasible implementation manners, the charging and discharging circuit further includes a resistor R5, a resistor R6, and a resistor R7, wherein:

The resistor R5 is connected between the collector of the transistor Q2 and the base of the transistor Q3;

The resistor R6 is connected between the positive pole of the battery and the positive pole of the capacitor C1;

The resistor R7 is connected between the cathode of the capacitor C2 and the LED.

In some feasible implementation manners, a unidirectional conduction diode D1 is connected between the negative pole of the capacitor C2 and the negative pole of the battery, the anode of the unidirectional conduction diode D1 is connected to the negative pole of the capacitor C2, and the negative pole connected to the negative terminal of the battery.

In some feasible implementation manners, the negative electrode of the battery is grounded.

Embodiments of the present invention have the following advantages or beneficial effects:

The battery low voltage alarm circuit in the embodiment of the present invention includes: an amplifying circuit, a charging and discharging circuit, and a light emitting diode, wherein: the amplifying circuit is connected to the battery, and is used for when the battery voltage reaches a preset low voltage threshold , obtaining the voltage of the battery, and amplifying and outputting the obtained voltage; the charging and discharging circuit is respectively connected with the amplifying circuit and the light emitting diode, and is used to alternately charge and discharge according to the voltage output by the amplifying circuit Discharge, so that the light-emitting diodes alternately appear the flickering effect of lighting and extinguishing; the light-emitting diodes are respectively connected between the positive pole of the battery and the charge-discharge circuit, so it can be seen that the circuit of the embodiment of the present invention When the battery voltage reaches the preset low voltage threshold, the light-emitting diode can be driven by the amplifier circuit and the charge-discharge circuit to alternately flash on and off, thereby achieving the effect of battery low-voltage alarm and reminding the user in time Recharge or replace the battery.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings on the premise of not paying creative efforts.

FIG. 1 is a schematic diagram of the module structure composition of an embodiment of the battery low voltage alarm circuit of the present invention.

FIG. 2 is a schematic diagram of the circuit structure of an embodiment of the battery low voltage alarm circuit of the present invention.

FIG. 3 is a schematic diagram of the circuit structure of another embodiment of the battery low voltage alarm circuit of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Referring to Fig. 1, the battery low-voltage circuit of the present invention may include an amplifying circuit T1, a charging and discharging circuit T2, and a light-emitting diode LED, wherein: the amplifying circuit T1 is connected to a battery BT for use when the voltage of the battery BT reaches a preset When the voltage threshold is low (for example, 2 volts, or other preset thresholds), the voltage of the battery BT is obtained, and the obtained voltage is amplified and output; the charging and discharging circuit T2 is respectively connected with the amplifying circuit T1 It is connected with the light-emitting diode LED, and is used to charge and discharge alternately according to the voltage output by the amplifying circuit T1, so that the light-emitting diode LED alternately appears the flickering effect of turning on and off; the light-emitting diode LED is respectively connected to Between the positive pole of the battery BT and the charging and discharging circuit T2.

When the battery voltage reaches the preset low-voltage threshold, the circuit of the embodiment of the present invention can drive the light-emitting diode to alternately turn on and off through the amplifier circuit and the charge-discharge circuit, thereby achieving the effect of battery low-voltage alarm , and remind the user to charge or replace the battery in time.

Further referring to FIG. 2 , the circuit structure of an embodiment of the battery low voltage warning circuit of the present invention may include an amplifying circuit T1, a charging and discharging circuit T2, and a light-emitting diode LED, wherein: the amplifying circuit T1 includes a resistor R1, an adjustable resistor VR1 , triode Q1, and triode Q2, the resistor R1 and the adjustable resistor VR1 are connected in series between the positive and negative poles of the battery; the base of the triode Q1 is connected to the adjustable end of the adjustable resistor VR1, and the Both the emitters of the triode Q1 and the triode Q2 are connected to the negative pole of the battery, the collector of the triode Q1 is connected to the base of the triode Q2, and the collector of the triode Q2 is connected to the positive pole of the battery . The charging and discharging circuit T2 includes a transistor Q3, a capacitor C1, a transistor Q4, and a capacitor C2, the base of the transistor Q3 and the negative pole of the capacitor C1 are connected to the collector of the transistor Q2; the emitter of the transistor and The positive pole of the capacitor C1, the positive pole of the capacitor C2, and the collector of the triode Q4 are connected to the positive pole of the battery; the base of the triode Q4 is connected to the collector of the triode Q3. The emitter of the triode Q4 is connected to the negative pole of the battery; the negative pole of the capacitor C2 is connected to the light emitting diode.

Further referring to FIG. 3 , on the basis of the example shown in FIG. 2 , in some feasible implementation manners, on the basis of the circuit in FIG. 2 , one or more of the following circuit structures may also be included.

1. The amplifying circuit T1 also includes a resistor R2, a resistor R3, and a resistor R4, wherein:

The resistor R2 is connected between the positive pole of the battery and the collector of the triode Q1;

The resistor R3 is connected between the positive pole of the battery and the collector of the triode Q2;

The resistor R4 is connected between the emitters of the triode Q1 and the triode Q2 and the negative pole of the battery.

2. The charging and discharging circuit T2 also includes a resistor R5, a resistor R6 and a resistor R7, wherein:

The resistor R5 is connected between the collector of the transistor Q2 and the base of the transistor Q3;

The resistor R6 is connected between the positive pole of the battery and the positive pole of the capacitor C1;

The resistor R7 is connected between the cathode of the capacitor C2 and the LED.

3. A one-way conduction diode D1 is connected between the negative pole of the capacitor C2 and the negative pole of the battery, the positive pole of the one-way conduction diode D1 is connected to the negative pole of the capacitor C2, and the negative pole is connected to the negative pole of the battery connected. In the specific implementation, the function of the unidirectional conduction diode D1 is to form a loop with the LED and the battery when the battery is fully charged, and keep the LED and the like in a constant light state, thereby reminding the user that the battery is sufficient.

In a specific implementation, as shown in FIG. 2 or FIG. 3 , the negative electrode of the battery may be grounded.

The working principle of the circuit of the embodiment of the present invention will be briefly introduced below with reference to FIG. 3 .

When the battery BT (assuming its voltage is between 2 volts and 3.3 volts) is fully charged, the operating voltage of the battery BT is much higher than the operating voltage of the LED and D1, so that the LED is always on.

When the voltage of BT drops to about 2V, a path is formed by R1 and VR1, and Q1 and Q2 are turned on to form a two-pole amplifier circuit. This part of the circuit forms a large operating current to provide operating voltage for the subsequent circuit.

At the beginning of the work, the capacitor C1 cannot change abruptly, so the initial voltage of C is 0, and R6, R5 and the conducting R4 form a path, so that the base voltage of Q3 is higher, and Q3 is not conducting. As the circuit charges C1, the voltage of C1 rises, and the base voltage of Q3 drops. When the base voltage is 0.6V lower than the emitter voltage, Q3 turns on, and its collector current makes Q4 turn on. After Q4 is turned on, the capacitor C2 is charged by the Q4 collector and emitter. At the same time, R6, LED, and R7 form a discharge circuit. When the voltage is charged to a certain value, the LED will light up, and the discharge process will start at the same time. When the discharge is completed, the LED will go out.

However, after the discharge is completed, since the battery voltage still exists, the charging and discharging process of C1 and C2 can be started again. So repeated, the flickering effect of the LED is formed.

The implementation methods described above do not constitute a limitation to the scope of protection of the technical solution. Any modifications, equivalent replacements and improvements made within the spirit and principles of the above implementation methods shall be included in the protection scope of the technical solution.

Claims (5)

1. a kind of battery low-voltage warning circuit, it is characterised in that including：Amplifying circuit, charging and discharging circuit and light-emitting diodes Pipe, wherein：

The amplifying circuit is connected with the battery, for when the cell voltage reaches default low voltage threshold, obtaining The voltage of the battery, and the voltage of acquisition is amplified output；

The charging and discharging circuit, is connected with the amplifying circuit and the light emitting diode respectively, for amplifying electricity according to described The voltage alternately charging and discharging of road output, so that the light emitting diode is alternately present the flicker effect lighted and extinguish Really；

The light emitting diode, is connected between the positive pole of the battery and the charging and discharging circuit；

The charging and discharging circuit includes triode Q3, electric capacity C1, triode Q4, electric capacity C2, wherein：

The negative pole of the base stage of the triode Q3 and the electric capacity C1 is connected with the colelctor electrode of the triode Q2；

The positive pole of the emitter stage of the triode and the electric capacity C1, and the electric capacity C2 positive pole, and three pole The colelctor electrode of pipe Q4 is connected with the positive pole of the battery；

The base stage of the triode Q4 is connected with the colelctor electrode of the triode Q3, emitter stage and the electricity of the triode Q4 The negative pole in pond is connected；

The negative pole of the electric capacity C2 is connected with the light emitting diode；

One-way conduction diode D1, the one-way conduction two are connected between the negative pole of the electric capacity C2 and the negative pole of the battery The positive pole of pole pipe D1 is connected with the negative pole of the electric capacity C2, and negative pole is connected with the negative pole of the battery.

2. battery low-voltage warning circuit as claimed in claim 1, it is characterised in that the amplifying circuit include resistance R1, Adjustable resistance VR1, triode Q1, triode Q2, wherein：

The resistance R1 and adjustable resistance VR1 are connected between the both positive and negative polarity of the battery；

The base stage of the triode Q1 is connected with the adjustable end of the adjustable resistance VR1, the triode Q1 and the triode Negative pole of the emitter stage of Q2 with the battery is connected, the base stage phase of the colelctor electrode of the triode Q1 and the triode Q2 Even, the colelctor electrode of the triode Q2 is connected with the positive pole of the battery.

3. battery low-voltage warning circuit as claimed in claim 2, it is characterised in that the amplifying circuit also includes resistance R2, resistance R3, resistance R4, wherein：

The resistance R2 is connected between the colelctor electrode of the positive pole of the battery and the triode Q1；

The resistance R3 is connected between the colelctor electrode of the positive pole of the battery and the triode Q2；

The resistance R4 is connected between the emitter stage of the triode Q1 and triode Q2 and the negative pole of the battery.

4. the battery low-voltage warning circuit as described in claim 1-3, it is characterised in that the charging and discharging circuit also includes electricity Resistance R5, resistance R6 and resistance R7, wherein：

The resistance R5 is connected between the base stage of the colelctor electrode of the triode Q2 and the triode Q3；

The resistance R6 is connected between the positive pole of the positive pole of the battery and the electric capacity C1；

The resistance R7 is connected between the negative pole of the electric capacity C2 and the light emitting diode.

5. the battery low-voltage warning circuit as described in claim 1-3, it is characterised in that the negative pole ground connection of the battery.