RT8301A

® RT8301A 8-CH Constant Current LED Driver for Display Backlight General Description The RT8301A is a 8-CH constant current sink LED drivers with Dynamic Headroom Control (DHC) function. RT8301A can provide well current matching ability, adjustable VSET to choose the suitable dropout voltage across the MOS / BTJ. Beside that, DHC will provide the stable VFB dimming, thus voltage ripple is kept as small even during the dimming. The RT8301A provides four channel constant currents with less than 3% differences in output current value among the 8-CH and ICs respectively. The constant current is adjustable by each channel external resistor (RISET). The LED brightness can also be adjusted via the EN/PWM pin with PWM dimming duty from 1% to 100%. The RT8301A can operate with external components for high current applications. The DHC function generates feedback signal to DC/DC control loop and regulate the output voltage. When RT8301A selects the LED string with the highest forward voltage, and then the COMP is defined according to that particular string. The COMP voltage is then compared with the voltage of VSET to determine the voltage level of VFB, which therefore control the switching of the primary controller. RT8301A's protection features include Short LED Protection (SLP), Open LED Protection (OLP) and Over Temperature Protection (OTP). When any channel triggers protection function, LED will be turned off and the FAULT pin will pull low. The RT8301A is available in SOP-24 p...