Power compensation circuit of LED lamp

Abstract

The invention discloses a power compensation circuit of an LED lamp. The circuit comprises a rectification module, a constant-current driving module and an LED lamp string, wherein the rectification module is used for converting a high-voltage alternating current into a line voltage and then outputting the line voltage; the constant-current driving module is used for adjusting the current value ofa LED lamp string. The circuit further comprises a low-voltage DC power supply module, an acquisition module and a control module with a preset algorithm. The circuit has the advantages that the power of each LED lamp does not change along with the change of a stable voltage among different voltage stabilizing diodes of the same model, so the power among all the LED lamps is consistent; the powerof a single LED lamp does not change along with the change of the working temperature of the voltage stabilizing diodes, so the consistency is better.

Description

technical field [0001] The invention belongs to the field of LED application technology, and in particular relates to a power compensation circuit of an LED lamp. Background technique [0002] In the application of smart LED lights, the control chip of the smart part needs low-voltage DC power supply. After the dimming signal is generated by the control chip, it is output to the constant current driver chip of the LED light string to adjust the current of the LED light string to change the brightness of the LED light string. The traditional control chip power supply method generally adopts such as figure 1 The power supply circuit shown above may use a switching power supply, but due to a series of problems such as high cost, large size, and conduction radiation of the switching power supply, it is not suitable for places where the load current is relatively small. [0003] exist figure 1 In the power supply circuit shown, the upper limit of the operating temperature of th...

AI Technical Summary

Problems solved by technology

The traditional control chip power supply method generally adopts such as figure 1 The power supply circuit shown above may use a switching power supply. Due to a series of problems such as high cost, large size, and conduction radiation of the switching power supply, it is not suitable for places where the load current is relatively small.

[0003] exist figure 1 In the power supply circuit shown, the upper limit of the operating temperature of the general LDO can only reach 70°C. Although the upper limit of the operating temperature of the better-quality LDO can reach 85°C, it is expensive, and the internal temperature of the LED lamp is as high as 100°C. This temperature has far exceeded the suitable operating temperature range of the LDO, so the LDO cannot work normally at this temperature

[0004] To solve this problem, there are two conventional methods: one is to increase the heat dissipation area of ​​the LED lamp to lower the internal temperature of the LED lamp to the suitable operating temperature range of the LDO, but this will increase the volume of the LED lamp and require Add extra cost; the second is not to use the LDO, directly use the Zener diode to supply power to the control chip, but the stable voltage of the Zener diode will change with the change of the operating temperature, which will cause the power of the same LED lamp to vary with the voltage of the Zener diode. The working temperature changes; and due to the difference in manufacturing process, the stable voltage of different Zener diodes of the same type is also different, which will cause the power of each LED lamp to change with the stable voltage, resulting in the difference between each LED lamp. Poor power consistency

Images