DESCRIPTION
The SD42509 is a step-down PWM control LED driver with a built-in internal power MOSFET. It achieves 1A continuous output current over a wide input supply range. It provides thermal shutdown circuit, current limiting circuit.
SD42509 adopts current mode control. Current mode operation provides fast transient response and simple loop stabilization design. SD42509 has high efficiency up to more than 90%, and has excellent constant current characteristic when the input/output voltage changed, with the excellent current accuracy within ± 1%.

FEATURES
* Maximum 1A output current
* 0.25Ω built-in power MOSFET
* 280kHz fixed frequency
* Excellent constant current accuracy ± 1%
* High efficiency up to 90%
* Thermal shutdown
* Cycle-by-cycle over current protection
* 6-20V input voltage range
* Drive LED string

APPLICATIONS
* Power LED driver