CN204810598U - Strong and weak light controlling circuit of tactics lamp - Google Patents

Abstract

The utility model discloses a strong and weak light control circuit of a tactical lamp, which comprises a power supply, a switch, an integrated chip, a triode, a light-emitting diode, an inductor, and a detection resistor. Electrode connection, the positive output terminal of the power supply is also connected to the integrated chip after being switched, the output terminal of the integrated chip is connected to the base of the triode, and the emitter of the triode is grounded after passing through the detection resistor; the voltage of the detection resistor is fed back to the integrated chip, and the integrated chip is based on The voltage across the sense resistor adjusts the PWM duty cycle. The utility model uses few electronic components, has low cost and produces less heat; the whole circuit is simple, easy to produce, and has high reliability and high detection precision.

Description

Strong and weak light control circuit of tactical lights

【Technical field】

The utility model relates to the field of electronic circuits, in particular to a strong and weak light control circuit of a tactical light.

【Background technique】

For the LED intensity control of general tactical lights, the single-chip microcomputer controls the enable terminal of the constant current chip, and uses different output duty ratios to drive the constant current source to achieve different currents to achieve intensity control. The disadvantage of the prior art is that the use of single-chip microcomputer and LED constant current chip for control and drive not only increases the complexity of the entire circuit, but also increases the overall cost of use. In addition, the detection reliability is poor and cannot meet the requirements of users.

The above deficiencies are worth addressing.

【Content of invention】

In order to overcome the deficiencies of the existing technology, the utility model provides a strong and weak light control circuit of a tactical light.

The technical scheme of the utility model is as follows:

The strong and weak light control circuit of the tactical light includes a power supply, a switch, an integrated chip, a triode, a light-emitting diode, an inductor, and a detection resistor. The light-emitting diode is connected to the collector of the triode, the positive output end of the power supply is also connected to the integrated chip after passing through the switch, the output end of the integrated chip is connected to the base of the triode, and the triode The emitter is grounded after passing through the detection resistor;

After the voltage of the detection resistor is fed back to the integrated chip, the integrated chip adjusts the PWM duty cycle.

Further, a reference voltage is provided in the integrated chip, and the integrated chip adjusts the PWM duty cycle by comparing the reference voltage with the voltage of the detection resistor.

Further, the triode is an NPN type triode.

According to the utility model with the above structure, its beneficial effect is that the utility model detects the current of the light-emitting diode by detecting the voltage on the resistor, and compares it with the reference value inside the single-chip microcomputer, and adjusts the current of the light-emitting diode by adjusting the PWM duty cycle , so as to achieve constant current. The utility model uses few electronic components, has low cost and produces less heat; the whole circuit is simple, easy to produce, and has high reliability and high detection precision.

【Description of drawings】

Fig. 1 is the schematic circuit diagram of the utility model embodiment.

In the figure, S1, switch; IC2, integrated chip; Q1, triode; L1, inductor; LED, light-emitting diode; R1, detection resistor.

【Detailed ways】

Below in conjunction with accompanying drawing and embodiment the utility model is further described:

As shown in Figure 1, the utility model provides a strong and weak light control circuit for a tactical light, including a power supply, a switch, an integrated chip, a triode, a light-emitting diode, an inductor, and a detection resistor. The collector of the inductance, light-emitting diode and triode is connected, the positive output terminal of the power supply is connected to the integrated chip after being switched, the output terminal of the integrated chip is connected to the base of the triode, and the emitter of the triode is grounded after passing through the detection resistor; After the voltage is fed back to the integrated chip, the integrated chip adjusts the PWM duty cycle.

Preferably, a reference voltage is provided in the integrated chip, and the integrated chip adjusts the PWM duty cycle by comparing the reference voltage with the voltage of the detection resistor.

Preferably, the triode is an NPN type triode.

The concrete working principle of this embodiment is:

The switch S1 is turned on, the circuit is turned on and powered on, the second pin of the integrated chip IC2 outputs a PWM signal according to the setting, and then the triode Q1 is turned on, the inductor L1 is charged, and at the same time supplies power to the light-emitting diode LED. Detect the current of the light-emitting diode LED by detecting the voltage on the detection resistor R1, detect it through AD input, and compare it with the reference value set in the microcontroller. If the current of the light-emitting diode LED is too large or too small, adjust the duty cycle of the PWM , so as to control the current of the light-emitting diode LED to become smaller or larger to achieve a constant current. It can be seen from the above that by adjusting the duty cycle of PWM, strong and weak light can be realized, and the brightness of the light-emitting diode LED can be adjusted.

The utility model uses few electronic components, has low cost and produces less heat; the whole circuit is simple, easy to produce, and has high reliability and high detection precision.

It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should belong to the protection scope of the appended claims of the present utility model.

The utility model patent has been exemplarily described above in conjunction with the accompanying drawings. Obviously, the implementation of the utility model patent is not limited by the above-mentioned methods, as long as various improvements made by the method concept and technical solutions of the utility model patent are adopted, or Directly applying the ideas and technical solutions of the utility model patent to other occasions without improvement is within the protection scope of the utility model.

Claims (3)

1. the strong and weak light control circuit of Tactical lights, comprise power supply, switch, integrated chip, triode, light-emitting diode, inductance and detect resistance, it is characterized in that, the cathode output end of described power supply is connected with the collector electrode of described inductance, described light-emitting diode and described triode successively after described switch, the cathode output end of described power supply is also connected with described integrated chip after described switch, the output of described integrated chip connects the base stage of described triode, emitter ground connection after described detection resistance of described triode;

The Voltage Feedback of described detection resistance is after described integrated chip, and described integrated chip adjusts PWM duty ratio.

2. the strong and weak light control circuit of Tactical lights according to claim 1, is characterized in that, is provided with reference voltage in described integrated chip, and described integrated chip is by PWM duty ratio described in the Voltage Cortrol of more described reference voltage and described detection resistance.

3. the strong and weak light control circuit of Tactical lights according to claim 1, is characterized in that, described triode is NPN type triode.