The principle of adjusting the brightness of a car light usually involves PWM (Pulse Width Modulation) technology. PWM is a common method of adjusting the brightness of electronic devices (such as LED lights) by controlling the duty cycle of the signal to adjust the switching elements in the circuit, thereby controlling the average power of the output signal and thus controlling the brightness.
In a car lamp, a control circuit is usually used to generate a PWM signal, which is sent to the drive circuit of the head. The drive circuit controls the current output from the power supply to the lamp according to the duty cycle of the PWM signal, and then controls the brightness of the lamp. The larger the duty cycle, the longer the current received by the lamp, and the higher the brightness; The smaller the duty cycle, the shorter the current received by the lamp and the lower the brightness.
By adjusting the duty cycle of the PWM signal, the brightness of the headlights can be precisely controlled to meet the brightness needs of different situations, such as reducing the brightness to reduce glare when driving at night, increasing the brightness to improve visibility during daytime driving, etc.
Huihai H5524L lamp chip, cost-effective, supports 60V 80V 100V step-down, can achieve high and low brightness, high and low beam and other functions.
Product Description: The H5524L is a non-isolated constant current LED driver IC with simple peripheral circuitry and VFPWM continuous operation mode. The typical switching frequency of the H5524L is fixed at 130kHz, and due to the fixed PWM operation mode, a smaller value of inductance can be used in the application, which can effectively save the space of the whole machine. The H5524L can switch between two functions by controlling the MODE port, MODE is high brightness mode when it is suspended, and MODE is low light mode with 50% load current when it is connected to high level.
The H5524L is packaged in an ESOP-8 package, and the heatsink at the lower part of the chip is connected to the drain pin, which can effectively dissipate heat from the chip.
Product Features: l Wide voltage 8V-90V input range.
l Typical 130kHz switching frequency.
l High efficiency: up to 95%.
l The output current can be as high as 15a (the allowance should be left on the glass fiber board).
l Built-in intelligent temperature protection, high temperature current drop.
l Built-in 100V low internal resistance MOS
l Built-in 55V regulator tube.
l Average current working mode.
l Integrated output short-circuit protection function.
Typical Applications. l DC or AC input LED driver.
l RGB backlight LED driver.
l Electric bicycle lighting.
l High power LED lighting.
l Automobile lighting, etc.