EV3302DG-00A 1.3A Fixed Frequency White LED Driver Evaluation Board The Future of Analog IC Technology DESCRIPTION FEATURES The EV3302DG-00A is an evaluation board for the MP3302DG, a step-up converter designed for driving up to 27 white LEDs from a single cell lithium Ion battery. The EV board is optimized for the load of 3 white LEDs in series, 9 strings panel. • • • • • The MP3302 uses current mode, fixed frequency architecture to regulate the LED current, which is measured through an external current sense resistor. Its low 208mV feedback voltage reduces power loss and improves efficiency. The MP3302 monitors the output voltage and turns off the converter if an over-voltage condition is present due to an open circuit condition. 3.3V to 6V Input Voltage Range Drives up to 27 White LEDs Up to 87% Efficiency Open Load Shutdown Fully Assembled and Tested APPLICATIONS • • • • Cell Phones Handheld Computers and PDAs Digital Still Cameras Small LCD Displays “MPS” and “The Future of Analog IC Technology” are Registered Trademarks of Monolithic Power Systems, Inc. The MP3302 includes under-voltage lockout, current limiting and thermal overload protection preventing damage in the event of an output overload. The MP3302 is available in small 8-pin QFN (2mm x 3mm) package. ELECTRICAL SPECIFICATIONS Parameter Input Voltage Number of LEDs Symbol Value Units VIN 3.3 – 6 27 V EV3302DG-00A EVALUATION BOARD Efficiency vs VIN 95% EFFICIENCY (%) 90% 85% 80% 75% (L x W x H) 1.8” x 1.8” x 0.4” 4.6cm x 4.6cm x 1.0cm Board Number MPS IC Number EV3302DG-00A MP3302DG EV3302DG-00A Rev. 1.1 10/18/2007 70% 3 4 5 6 INPUT VOLTAGE(V) www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2007 MPS. All Rights Reserved. 7 1 EV3302DG-00A – 1.3A FIXED FREQUENCY WHITE LED DRIVER EVALUATION BOARD SCHEMATIC L1 VIN JP1 Bias 2 5 IN SW LED+ 4 EN EN LED- MP3302 FB GND 6 GND 1 EV3302DG-00A BILL OF MATERIALS Qty Ref 2 C1,C2 1 C3 1 C4 1 D1 1 1 L1 LED1 to LED10 R1 1 R2 1 U1 10 1 Value Description 4.7µF Ceramic Capacitor, 16V, X5R NS Diode Schottky, 30V, 1A 4.7µH Inductor CN1 EV3302DG-00A Rev. 1.1 10/18/2007 0805 Murata GRM21BR61C475KA88 0805 Murata GRM21BR71E474KA01L SMA Diodes Inc DFLS130L-F SMD Cooper SD10-4R7-R 0805 Yageo R0805FR-071R1L QFN8 MPS MP3302DG JST SM02B-BHSS-1-TB Not Stuffed 1.10Ω Resistor, 1% NS Part Number Not Stuffed 0.47µF Ceramic Capacitor, 25V, X7R NS Package Manufacturer Not Stuffed White Led Driver Connector www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2007 MPS. All Rights Reserved. 2 EV3302DG-00A – 1.3A FIXED FREQUENCY WHITE LED DRIVER PRINTED CIRCUIT BOARD LAYOUT Figure 1—Top Silk Layer Figure 2—Top Layer Figure 3—Bottom Layer EV3302DG-00A Rev. 1.1 10/18/2007 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2007 MPS. All Rights Reserved. 3 EV3302DG-00A – 1.3A FIXED FREQUENCY WHITE LED DRIVER QUICK START GUIDE 1. Connect the positive and negative terminals of the load panel (3 white LEDs in series, 9 stings paralleled, each string have a 43ohm droop resistor) to the LED+ and LED- pins on the EV board, respectively. 2. Connect the positive and negative terminals of the power supply (3.3V ~ 6V) to the VIN and GND pins on the EV board, respectively. 3. Drive EN pin high (1.5V < Ven < Vin) to enable the MP3302. 4. Apply a DC voltage of 0.7V to 1.4V on EN pin for analog dimming. Maximum brightness (180mA typical) occurs with 1.4V voltage applied. 5. For PWM dimming mode, apply a PWM rectangular waveform with a minimum voltage less than 0.5V and a maximum greater than 1.5V on EN pin. The frequency of the PWM signal is recommended between 100Hz to 10kHz. 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. EV3302DG-00A Rev. 1.1 10/18/2007 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2007 MPS. All Rights Reserved. 4