EV3388DR-01A 8 strings White LED Driver Evaluation Board This board can be used for MP3388S w/o external component change The Future of Analog IC Technology DESCRIPTION FEATURES The EV3388DR-01A is an evaluation board for the MP3388DR, a step-up converter designed for large liquid-crystal displays that employ an array of LEDs as the light source. It can drive up to 8 strings in parallel and 10 LEDs per string. • • • • The MP3388 uses internal switch current mode, fixed frequency architecture and includes current ballast in each string terminal, which achieves ±3% current regulation accuracy between strings. Low feedback voltage at each LED string help reduce power loss and improve efficiency. The MP3388 has multiple features to protect the converter from fault conditions, including under-voltage lockout, current limiting, over voltage, short LED, open LED and thermal shut-down protection. The MP3388 is available in small QFN24 (4mmx 4mm)，TSSOP28 and SOIC28 package. • • • • 4.5V to 25V Input Voltage Range Up to 89% Efficiency Programmable Over Voltage Protection Drives up to 8 Strings Parallel and 10 LEDs in Series. ±3% Current Regulation Accuracy Between Strings Selectable Switching Frequency: 1.25MHz and 625kHz Open and Short LED Load Protection Thermal Shutdown APPLICATIONS • • • • Notebook PC Small LCD TV Handy Terminals Display Automotive Systems and Tablet Computer All MPS parts are lead-free, halogen free, and adhere to the RoHS directive. For MPS green status, please visit MPS website under Quality Assurance. “MPS” and “The Future of Analog IC Technology” are Registered Trademarks of Monolithic Power Systems, Inc. ELECTRICAL SPECIFICATIONS Parameter Input Voltage Symbol Value VIN 4.5 – 25 V 8 strings parallel and 10 LEDs each string LEDs # LED Current /String Units ILED 20 mA EV3388DR-01A EVALUATION BOARD (L x W x H) 5.7cm x 3.2cm x 1.0cm Board Number MPS IC Number EV3388DR-01A MP3388DR EV3388DR-01A Rev.1.1 www.MonolithicPower.com 3/17/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 1 EV3388DR-01A: 50V, 8-STRING, STEP-UP, WHITE LED DRIVER EVALUATION BOARD SCHEMATIC U1 EV3388DR-01A Rev.1.1 www.MonolithicPower.com 3/17/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 2 EV3388DR-01A: 50V, 8-STRING, STEP-UP, WHITE LED DRIVER EV3388DR-01A BILL OF MATERIALS Qty Ref Value 1 C1 4.7µF 1 C2 NC 1 C3 2.2µF 1 C4 NC 1 C5 68nF 4 C6,C8, C9,C11 NC 1 C7 0.47µF 1 C10 100pF 1 D1 1 F1 1 L1 Description Ceramic Capacitor, 50V, X7R Package Manufacturer 1210 Murata Part Number GRM32ER71H475KA88L 1210 Ceramic Capacitor, 50V, X7R 1210 TDK C3225X7R1H225 1210 Ceramic Capacitor, 50V, X7R 0603 Murata GRM188R71H683KA01D 0805 Murata GRM21BR61C474KA88 0603 Murata GRM1885C1H101JA01D SMA Diodes Inc 0603 Ceramic Capacitor, 16V, X5R Ceramic Capacitor, 50V, COG Diode Schottky, 60V, 1A Fuse, 2.5A 1206 10µH Inductor,2.47A SMD Cooper 10µH Inductor,2.5A SMD TDK P- channel MOSFET SO8 Resistor, 1% 0603 1 M1 1 R1 324kΩ 3 R2,R5, R11 NC 1 R3 10kΩ Resistor, 1% 2 R4,R6 20kΩ 1 R7 1 DFLS160-F DR73-100 SLF10145T-100M2R5-H AM4499P Yageo RC0603FR-07324KL 0603 Yageo RC0603FR-0710KL Resistor, 5% 0603 Yageo RC0603JR-0720KL 60.4kΩ Resistor, 1% 0603 Yageo RC0603FR-0760K4L ,R8 100kΩ Resistor, 5% 0603 Yageo RC0603JR-07100KL 2 R9,R10 2kΩ Resistor, 5% 0603 Yageo RC0603JR-072KL 8 R12~R19 0Ω Resistor, 5% 0603 Yageo RC0603JR-070RL 1 U1 LED Driver IC QFN24 MPS 0603 MP3388DR EV3388DR-01A Rev.1.1 www.MonolithicPower.com 3/17/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 3 EV3388DR-01A: 50V, 8-STRING, STEP-UP, WHITE LED DRIVER EVB TEST RESULTS Performance waveforms are tested on the evaluation board. VIN =15V, 10 LEDs in series, 8 strings parallel, 20mA/string, unless otherwise noted. Steady State Efficiency vs. Input Voltage Vin Startup EFFICIENCY(%) 100 95 90 85 80 Vsw 20V/div Vsw 20V/div VLED8 500mV/div VOUT 20V/div VIN 10V/div VOUT/AC 500mV/div ILED 100mA/div 75 70 4 9 14 19 24 ILED 100mA/div 29 2ms/div 400ns/div INPUT VOLTAGE (V) Ven Startup PWM Dimming Open LED Protection fPWM=2kHz, DPWM=50% open all LED strings at working Vsw 20V/div Vsw 20V/div Vsw 20V/div VOUT 20V/div VOUT 20V/div VPWMI 5V/div VOUT 20V/div VEN 5V/div VFAULT 5V/div ILED 100mA/div ILED 100mA/div ILED 100mA/div 2ms/div 200us/div Short LED Protecton Short LED Protection short Vout to LEDx at working short Vout to GND at working Vsw 20V/div Vsw 20V/div VOUT 20V/div VLED8 20V/div VOUT 20V/div 400ms/div VFAULT 10V/div ILED 100mA/div ILED 100mA/div 1ms/div 200us/div EV3388DR-01A Rev.1.1 www.MonolithicPower.com 3/17/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 4 EV3388DR-01A: 50V, 8-STRING, STEP-UP, WHITE LED DRIVER PRINTED CIRCUIT BOARD LAYOUT Figure 1—Top Layer Figure 2—Bottom Layer EV3388DR-01A Rev.1.1 www.MonolithicPower.com 3/17/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 5 EV3388DR-01A: 50V, 8-STRING, STEP-UP, WHITE LED DRIVER QUICK START GUIDE 1. Connect the positive and negative terminals of the load panel (10 white LEDs in series, 8 strings paralleled) to the LED+ and LED1~8 pins on the EV board, respectively. 2. Connect the positive and negative terminals of the power supply (4.5V ~ 25V) to the VIN and GND pins on the EV board, respectively. 3. Drive EN pin high (2.5V < Ven < 5V) to enable the MP3388. 4. For PWM dimming, apply a PWM rectangular waveform with a minimum voltage less than 0.5V and a maximum greater than 2.5V on PWM DIM pin. The frequency of the PWM signal is recommended between 200Hz to 2kHz.and Duty of PWM range from 10% to 100%. NOTICE: The information in this document is subject to change without notice. Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not assume any legal responsibility for any said applications. EV3388DR-01A Rev. 1.1 www.MonolithicPower.com 3/17/2016 MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited. © 2016 MPS. All Rights Reserved. 6