LED constant current drive circuit and device using step-down constant current drive unit

Abstract

The invention relates to an LED constant current drive circuit using a step-down constant current drive unit and an LED automotive lighting device including the circuit. The DC power supply of the LED constant current drive circuit provides two kinds of power supplies, a far light end power supply and a near light end power supply. The reverse polarity protection unit performs reverse polarity protection on the LED constant current drive circuit. The far light end power supply or the near light end power supply after voltage and constant current is provided to the LED lighting unit to drive the LED lighting unit. Switch between high beam end and low beam end. The LED constant current driving circuit and the LED automobile lighting device including the circuit of the present invention can realize the far and near light adjustment of the LED lighting module, and have the characteristics of simple structure and stable performance.

Description

technical field [0001] The invention relates to the field of LED automobile lamp lighting, in particular to an LED step-down constant current drive circuit and an LED automobile lighting device including the circuit. The invention also includes an LED automobile lamp using the circuit. Background technique [0002] With the continuous development of science and technology, LED, as a new type of green light source, has the characteristics of energy saving, environmental protection, and high efficiency. [0003] Widely used, various LED drive circuits have also appeared. LED car lights adopt the connection method of multiple high-power LEDs in series and then in parallel, which requires the LED drive circuit to have the characteristics of wide input voltage and large drive current. [0004] At present, the LED lamp driving circuit adopts the driving method of constant current driving chip and external MOS tube to ensure the large current required by the LED car lamp and the ...

AI Technical Summary

Problems solved by technology

The far and near light switching circuit mostly uses two constant current drive circuits, and realizes the far and near light switching by controlling one of the control circuits. This circuit has the disadvantages of complex circuit, high cost, easy damage and high power consumption.

There are also a few that use a driving circuit to switch between far and near light, but there are many components, the circuit is complicated, and another power supply needs to be connected from the car battery, which makes it inconvenient to use, and the driving circuit is always in a charged working state, causing excessive power consumption.

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