MP3378 24 V, 4-Channel WLED Controller Plus High-Efficiency Buck Converter DESCRIPTION FEATURES The MP3378 is a one-chip solution designed for WLED Controller: monitor applications. It includes a step-up 4-String, Max 350 mA/String WLED controller with 4 current channels for Controller backlighting and a high-efficiency buck Up to 24 V Input Voltage Range converter for internal bus voltage or standby 2.5% Current Matching Accuracy 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 Open and Short LED 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 the special dimming mode request. In Inductor/Diode Short Protection addition, rich protection modes are integrated including OCP, OTP, UVP, OVP, LED Buck Converter: short/open protection, and inductor/diode short 144 m/58 m Low Rds(on) Internal Power protection. MOSFETs The high-efficiency buck converter operates in Low Quiescent Current current mode with a built in MOSFET and Fixed 235 kHz Switching Frequency synchronous rectifier. It offers a very compact Frequency Sync from 250 kHz to 2 MHz solution to achieve excellent load and line External Clock regulation. Full protection features include OCP AAM Power-Save Mode and thermal shutdown. Internal Soft Start The MP3378 is available in SOIC28 and OCP and Hiccup TSSOP28EP package. Over-Temperature Protection Output Adjustable from 0.8 V 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. MP3378 Rev. 1.01 www.MonolithicPower.com 1 5/26/2017 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. 2017 MPS. All Rights Reserved. MP3378 4-CHANNEL WLED CONTROLLER PLUS BUCK CONVERTER TYPICAL APPLICATION L1 D1 VIN C1 C2 M1 R11 23 24 GATE VIN1 R10 C3 22 25 ISENSE VCC1 R1 26 1 GND1 COMP R3 27 9 EN OVP C4 R2 2 8 OSC LED1 7 4 ADIM LED2 28 6 PWM LED3 MP3378 R4 3 5 ISET LED4 R6 15 20 VIN VIN2 BST C7 47 C4 L2 10 H 5 V 0.1F 22 F 16 21 SW SYNC GATE C5 R8 40.2 k 66 F R7 14 12 VCC2 FB C6 51 k R9 0.1 F 7.5 k 13 19 AAM AGND GND2 R5 75 k 17, 18 MP3378 Rev. 1.01 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