ev3412ej-00a 1.1a synchronous boost white led driver evaluation board ev3412ej-00a rev. 1.0 www.monolithicpower.com 1 1/11/2010 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2010 mps. all rights reserved. the future of analog ic technology description the ev3412ej-00a is an evaluation board for the mp3412, a synchronous step-up wled driver with true output load disconnection function. the ev board is designed for driving one wled. the mp3412 can startup from an input voltage as low as 0.8v and provides in-rush current limiting as well as output short circuit protection. the open load protection is also integrated a switching frequency of 1mhz minimizes overall solution footprint by allowing the use of tiny, low profile inductors and ceramic capacitors. current mode pwm control with internal compensation reduces external parts, thereby saving critical board space. the device also features low shutdown current of under 1a. the true output disconnect feature allows the output to be completely discharged in shutdown. it also limits the inrush of current during start-up, minimizing surge current seen by the input supply. the mp3412 is available in 6-pin thin sot23 package. features ? input range: 0.8v to 4.4v ? 0.8v low start-up voltage ? internal power mosfet and synchronous rectifier ? 1mhz fixed switching frequency ? up to 96% efficiency ? true output load disconnect ? open-load protection ? short-circuit protection ? fully assembled and tested applications ? cellular phones ? digital cameras ? handheld instruments ? wireless handsets ? gps receivers electrical specifications parameter symbol value units input voltage v in 0.8~4.4 v # of wleds 1 led current i led 200 ma ?mps? and ?the future of analog ic technology? are registered trademarks of monolithic power systems, inc. ev3412ej-00a evaluation board (l x w x h) 2.0? x 2.0? x 0.4? 5.0cm x 5.0cm x 1.0cm board number mps ic number ev3412ej-00a MP3412EJ 50 55 60 65 70 75 80 85 90 95 100 012345 v in (v) efficiency (%) efficiency i o =200ma i o =80ma ldo mode boost mode
ev3412ej-00a ? 1.1a synchronous boos t white led driver evaluation board ev3412ej-00a rev. 1.0 www.monolithicpower.com 2 1/11/2010 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2010 mps. all rights reserved. evaluation board schematic ev3412ej-00a bill of materials qty ref value description package manufacturer part number 1 c1 4.7f ceramic capacitor,16v,x7r 1206 murata grm31cr71c475ka01l 3 c2, c3, c5 nc 1 c4 2.2f ceramic capacitor,16v,x7r 0805 murata grm21br71c225ka12l 1 l1 4.7h inductor 1.36a d63lcb toko #a921cy-4r7m=p3 1 r1 0 ? 5% 0603 any 3 r2, r4, r6 nc 1 r3 1 ? 1% 0805 yageo rc0805fr-071rl 1 r5 20k ? 5% 0603 any 1 u1 MP3412EJ mps wled driver tsot23-6 mps MP3412EJ-lf-z r1
ev3412ej-00a ? 1.1a synchronous boos t white led driver evaluation board ev3412ej-00a rev. 1.0 www.monolithicpower.com 3 1/11/2010 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2010 mps. all rights reserved. printed circuit board layout figure 1?top layer figure 2?bottom layer
ev3412ej-00a ? 1.1a synchronous boos t white led driver evaluation board notice: the information in this document is subject to change wi thout notice. users should warra nt and guarantee that third party intellectual property rights are not infringed upon w hen integrating mps products into any application. mps will not assume any legal responsibility for any said applications. ev3412ej-00a rev. 1.0 www.monolithicpower.com 4 1/11/2010 mps proprietary information. unaut horized photocopy and duplication prohibited. ? 2010 mps. all rights reserved. quick start guide 1. connect the positive and negative terminals of one wled to the led+ and led- pins on the ev board, respectively. 2. connect the positive and negative terminals of the power supply to the vin and gnd pins on the ev board, respectively. turn the power supply on. 3. drive en pin high (v en >0.8v) to enable the mp3412. 4. for pwm dimming mode, apply a pwm signal with high level greater than 0.8v to the en pin. the typical pwm frequency should be 200hz. the wled brightness can be controlled by the pwm dimming duty cycle.
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