OC5228

OC5228 is a multi-function average current mode LED constant current driver with a simple peripheral circuit, designed for step-down BUCK high-power dimming constant current LED applications in the 5 - 100V input voltage range. The chip's PWM port supports ultra-small duty cycle PWM dimming and can respond to a minimum pulse width of 60ns. When the PWM port is high, the chip operates normally; when low, the chip output is disabled. The chip employs an average current control algorithm, achieving output current regulation accuracy of ≤±3%, with minimal sensitivity to input/output voltage and system inductance variations. The chip integrates internal loop compensation, simplifying the peripheral circuit and enhancing system stability and reliability. The chip achieves three-mode switching by controlling the LD port. When LD is floating, the system operates in high-brightness mode; when LD is connected to VDD, the system enters low-brightness mode at 1/2 current; when LD receives an analog dimming signal of 0.2 - 1.2V, the system operates in analog dimming mode. The LD high/low brightness switching mode is used to implement high beam/low beam switching in automotive LED lighting applications. In LD analog dimming mode, when the port voltage falls below 0.2V, the output is disabled.

Applications

• Landscape wash lights
• Stage dimming effect lights
• High-end automotive lighting
• LCD backlight illumination
• Architectural lighting

Key features

• High-dimming support, 65536:1 dimming ratio
• Wide input voltage: 5 - 100V
• Average current operating mode
• High efficiency: up to 95%
• Adjustable output current range: 60mA ~ 1.2A
• Integrated 100V/2A MOS
• Built-in 5.5V Zener diode
• Maximum operating frequency: 1MHz
• Constant current accuracy ≤±3%
• PWM/analog/segmented dimming support
• Package: SOP8