All Car Led Headlights Are Driven:
1. Why does the LED light need to be driven? The LED light cannot directly use the conventional mains
grid voltage. Due to the characteristics of the LED light source, in order to meet the special voltage and
current requirements of the LED, a specially designed voltage conversion device must be used to make it
LED works normally, so LED lamps have a power drive mode that is different from traditional lamps;
2. The output current of the constant current drive circuit is constant, while the output DC voltage varies
within a certain range with the size of the load resistance. The smaller the load resistance, the lower the
output voltage. The larger the load resistance, the output The higher the voltage. The constant current
circuit is not afraid of the load short circuit, but it is strictly forbidden to open the load completely;
3. It is ideal for a constant current drive circuit to drive LEDs, but the price is relatively high. It should be
noted that the maximum withstand current and voltage values used, which limit the number of LEDs used.
Driver: A power converter (converter) that converts the input "constant voltage" into a "constant current"
suitable for LED use;
Decoder: Equivalent to resistance, halogen lamp power is high, LED power is generally low, current is small,
CAN system matching failure alarm, so add resistance to increase power.
Capacitance decoder: uf is mainly to solve some interference waves.
The working principle of the decoder: the halogen bulb power of the original car is generally 55W,
while the power of the LED headlight is only about 30W. As the power is reduced and the current is reduced,
the trip computer detects that the current is different from the original current, and judges that the headlights
are malfunctioning, so the "alarm indicator" on the dashboard lights up. Therefore, in order to solve the
problem of fault indicator warning, it is necessary to install a "decoder" and increase the resistance. The power
and current are correspondingly increased to the same level as before, and the trip computer will not alarm.