MP3378E 4-Channel WLED Controller with High-Efficiency Buck Converter DESCRIPTION FEATURES The MP3378E is a one-chip solution specially WLED Controller: designed for monitor applications. The 4-String, Max 350mA/String, WLED MP3378E includes a step-up WLED controller Controller with four current channels for backlighting, and Up to 24V Input Voltage Range a high-efficiency buck converter for internal bus 2.5% Current Matching Accuracy voltage or standby power. Programmable Switching Frequency The 4-string WLED controller drives an external PWM and Analog Dimming Mode MOSFET to boost up the output voltage from LED Open and Short Protection the input supply. It regulates the current in each Programmable Over-Voltage Protection LED string to the programmed value set by an Recoverable Thermal Shutdown Protection external current setting resistor. It supports both Over-Current Protection analog and PWM dimming independently to Over-Temperature Protection meet special dimming mode requests. Full Inductor/Diode Short Protection protection features for the WLED controller include OCP, OTP, UVP, OVP, LED short/open Buck Converter: protection, and inductor/diode short protection. 144m/80m Low R Internal Power DS(ON) The high-efficiency buck converter operates in MOSFETs the current mode operation with a built-in Low Quiescent Current MOSFET and a built-in synchronous rectifier. It Fixed 235kHz Switching Frequency offers a very compact solution to achieve Frequency Sync from 250kHz to 2MHz excellent load and line regulation. Full External Clock protection features for the buck converter Internal Soft Start include OCP and thermal shutdown. OCP and Hiccup Mode The MP3378E is available in a TSSOP-28 EP Over-Temperature Protection package. Output Adjustable from 0.8V APPLICATIONS Desktop LCD Flat Panel Displays Flat Panel Video Displays 2D/3D LCD TVs and Monitors All MPS parts are lead-free, halogen-free, and adhere to the RoHS directive. For MPS green status, please visit the MPS website under Quality Assurance. MPS and The Future of Analog IC Technology are registered trademarks of Monolithic Power Systems, Inc. MP3378E Rev. 1.02 www.MonolithicPower.com 1 5/26/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. 2017 MPS. All Rights Reserved. MP3378E 4-CHANNEL WLED CONTROLLER WITH BUCK CONVERTER TYPICAL APPLICATION L1 D1 VIN C1 C2 M1 R10 23 24 GATE VIN1 R9 C3 22 25 ISENSE VCC1 R1 26 1 GND1 COMP R3 27 9 EN1 OVP C4 R2 2 8 OSC LED1 7 4 ADIM LED2 28 6 PWM LED3 MP3378 R4 E 3 5 ISET LED4 R5 15 20 VIN VIN2 BST C7 47 C4 L2 10H 5V 0.1F 22F 16 21 SW SYNC SYNC C5 R7 66F R6 40.2k 14 12 VCC2 FB C6 51k R8 0.1F 7.5k 13 19 EN2 AGND GND2 17, 18 MP3378E Rev. 1.02 www.MonolithicPower.com 2 5/26/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. 2017 MPS. All Rights Reserved. String 1 String 2 String 3 String 4