EUP2588 ds2588 ver1.1 may 2011 1 4 strings high current white led driver with boost controller description the EUP2588 is a high power and high efficiency boost controller with 4-channel current sinker whic h is ideal for large lcd backlighting applications. EUP2588 uses current mode, fixed frequency architecture which can clamp the inductor peak curr ent each cycle. the switching frequency is programmable by an external frequency setting resistor. it drive s an external mosfet to boost up the output voltage from a 4.5v to 28v input supply. the EUP2588 regulates the current in each led string to the programmed value set by an external current setting resistor. the EUP2588 current matching can achieve 1.5% and regulation accuracy can reach 2%. a 3 a shutdown current and 0.85v (iled@180ma) feedback voltage and maximum 65v output allows for up to 18 high-power leds in series will greatly improve efficiency and reduce power dissipation. the device supports pulse width modulation (pwm) brightness dimming. during digital pwm dimming, the wled current is turned on/off at the duty cycle and frequency determined by the pwm signal on the pwmi pin. the EUP2588 integrated multiple protect functions, such as led open, led short, output over voltage, over thermal, input over current, and under voltage lockout (uvlo), these protection will prevent the lcd backlight from damage. EUP2588 is available in 16pin sop packages. features 3 a shutdown current 4 strings in parallel and up to 18 leds per string external pwm dimming control output voltage up to 65v up to 180ma drive capability for each string wide input voltage range 4.5v to 28v better than 1.5% led current regulation accuracy between strings boost switching frequency can be programmed by external resistor multiple fault protections -current limit protection -output short circuit detection -over-temperature protection -output over-voltage protection led current turn off in shutdown mode integrated uvlo/ over thermal protection minimal 0.5 s led on-time regulation thermal enhanced 16pin sop-16 package rohs compliant and 100% lead (pb)-free halogen-free applications lcd monitor led backlighting lcd-tv led backlighting typical application circuit figure 1. typical application circuits
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