LED lamp constant current power supply obsoleting dimmable 12 V incandescent light

Abstract

The invention discloses an LED lamp constant current power supply obsoleting a dimmable 12 V incandescent light. The LED lamp constant current power supply comprises an alternating current power supply circuit, a control circuit, a coupling output circuit and a ripple restraining circuit. The alternating current power supply circuit is connected with a 12 V alternating current power supply Uin and comprises an alternating current positive half-wave current loop and an alternating current negative half-wave current loop, wherein constant current control over the alternating current positive half-wave current loop and the alternating current negative half-wave current loop is achieved through a constant current driving chip U1 and a constant current driving chip U2 respectively. The coupling output circuit rectifies and filters secondary induction current generated by a secondary winding N2 of a magnetic integrated transformer TR and then outputs the secondary induction current to a load LED lamp, the ripple restraining circuit recycles harmonic waves THD and EMI, and the harmonic waves THD and the EMI are rectified and then are output to the load LED lamp. The constant current driving chip U1 and the constant current driving chip U2 are DU8968 integrated chips. The LED lamp constant current power supply is suitable for the 12 V alternating current power supply, the saved energy can maximally reach 95%, the electrical work power is improved without a bridge rectifier, reliability is improved without an electrolytic capacitor, the constant current precision is high, current ripples are small, the LED lamp does not flicker, and the circuits are environmentally friendly.

Description

technical field [0001] The invention belongs to the LED lamp constant-current power supply technology, in particular to an LED lamp constant-current power supply for eliminating dimmable 12-volt incandescent lamps. Background technique [0002] The luminous efficacy of an incandescent bulb is 15 lumens per watt. On April 3, 2014, CREE announced that it supplied 350 milliamperes of direct current to LED lamp beads with a color temperature of 5150 degrees K, and the measured LED luminous efficacy was 303 lumens! In other words, LED lamps only need 5% of the power consumption of incandescent lamps to get the same lumens as incandescent lamps. Replacing traditional incandescent bulbs with high-efficiency LED lights can save 95% of the energy. Governments around the world have formally legislated to stop production and sales of incandescent bulbs, just for the sake of carbon reduction and environmental protection. [0003] For non-dimmable high-voltage incandescent bulbs, repla...

AI Technical Summary

Problems solved by technology

However, it is not easy to replace the 12-volt low-voltage incandescent bulbs with LED lights for thyristor dimming

Various integrated circuit companies researched and developed special-purpose integrated circuits for LED lamps, such as the AC / DC quasi-resonant high power factor constant-current LED controllable LED lights produced by Shanghai Duty Cycle Electronic Technology Co., Ltd. Silicon dimming driver chip DU8968, but at present, including DU8968, most of the integrated chips specially used for thyristor dimming LED lamps are only suitable for high-voltage AC power supplies above 100 volts, and are not suitable for 12-volt low-voltage power supplies. The voltage drop of the type rectifier itself leads to a power drop, and the voltage of the full-load LED lamp may far exceed 12 volts. Therefore, it has become a globally recognized problem to replace the 12 volt low-voltage incandescent bulbs dimmed by silicon controlled rectifiers with LED lights.

Images