preliminary EUP2990 ds2990 ver0.1 aug. 2013 1 6 string white led driver with boost converter description the EUP2990 is a high efficiency boost regulator wi th 6 channel current sinker which is ideal for media s ize lcd backlighting applications. the device with integrated 2.5a/43v power mosfet uses current mode architecture and drives six strin gs in parallel and supports up to 10 pieces of leds per string. the switching frequency is programmable by an external frequency setting resistor. the EUP2990 regulates the current in each led string to the programmed value set by an external current setting resistor. the EUP2990 current matching can achieve 2%. to provide enough headroom for the operating o f current sink, boost converter monitors the minimum voltage of feedback pins and regulates an optimized output voltage for power efficiency. the EUP2990 has wide input voltage range from 2.5v to 24v and provides adjustable 5ma to 50ma led current. it provides cycle-by-cycle over current protection. the device supports pwm and analog brightness dimming functions for accurate led curre nt control. the EUP2990 integrated multiple protect functions, such as led open, led short, output over voltage, over thermal and under voltage lockout, these protections will prevent the lcd backlight from damage. the EUP2990 is available in a 33mm tqfn-20l package. typical application circuit features 2.5v to 24 v input voltage 6 strings in parallel and up to 10 wleds per string integrated 2.5a 43v mosfet output voltage up to 43v programmable full channel current from 5ma to 50ma direct pwm dimming up to 20khz pwm to analog dimming up to 20khz with 8 bit resolution better than 2% current regulation accuracy between strings multiple fault protections -current limit protection -over voltage protection -over temperature protection -wled open/short protection available in 3mm3mm tqfn-20 package rohs compliant and 100% lead (pb)-free halogen-free applications notebook lcd display backlight umpc lcd display backlight figure 1.
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