AS3834/3834B are 4 channel devices with integrated step-up controller to provide the necessary output voltage for the LED string supply. The SMPS feedback control optimises the power efficiency by adjusting the LED string supply voltage. Output current is up to 270mA per channel and built-in safety features include under-voltage and thermal shutdown as well as open and short LED detection.
The AS3833 is a 6 channel LED controller with a similar specification, delivering output current up to 250mA per channel.
Supply voltage range: 12V to 50V;
Absolute current accuracy ± 0.8%;
Channel to channel accuracy ±0.6%;
1 PWM input with internal phase shift;
Open LED detection and auto-disconnect;
Short LED protection and auto-turnoff;
Temperature supervision of external BJT;
BJT Beta compensation;
SMPS feedback control;
DCDC Softstart Function;
Over Voltage Protection (OVP).
Package options include SOIC-28 and TQFP-32