Product Overview
The OTK5228A is a constant-current LED driver from Orientek capable of 280mA output. 6V-30V input range. PWM and analog dimming control. SOT-89-5 package for efficient thermal dissipation. Suitable for single-string LED lighting and backlight applications.
Key Specifications
| Type | Constant Current LED Driver |
| Channels | 1 |
| Output Current | Up to 280 mA |
| Dimming | PWM + Analog |
| Efficiency | >85% |
| Supply Voltage | 6V to 30V |
| Protection | OCP, OTP, Open LED |
| Operating Temp | -40 to +85C |
| Package | SOT-89-5 |
Working Principle
The OTK5228A uses a step-down (buck) converter topology with integrated power MOSFET. The output current is set by an external sense resistor. PWM dimming controls brightness by enabling/disabling the output at high frequency. Analog dimming adjusts the internal reference voltage. The control loop maintains constant current through the LED string regardless of input voltage and LED forward voltage variations. Thermal foldback reduces current at high junction temperatures to prevent damage.
Applications
- LED backlight
- General illumination
- Signage
- Automotive lighting