MP1517

EV0043 (MP1517) 3A, 25V, 1.1MHz Step-Up Converter for WLED Applications The Future of Analog IC Technology EVALUATION BOARD DESCRIPTION The EV1517 is the evaluation board used to demonstrate the white LED driver capabilities of the MP1517. The low 0.7V feedback voltage offers higher efficiency in white LED driver applications including cell phone camera flash. Soft-start, cycle-by-cycle current limiting and input under voltage lockout prevent overstressing or damage to sensitive external circuitry at startup and output short-circuit conditions. Current-mode regulation and external compensation components allow the MP1517 control loop to be optimized over a wide variety of input voltages, output voltages and load current conditions. FEATURES • • • • • • • • • • • • • • • 4A Peak Current Limit Low 700mV Feedback Threshold Internal 150mΩ Power Switch Input Range of 2.6V to 25V 95% Efficiency Zero Current Shutdown Mode Under Voltage Lockout Protection Open Load Protection Soft-Start Operation Thermal Shutdown Tiny QFN16 (4mm x 4mm) Package Boost and SEPIC Regulators Handheld Computers Cell Phone Camera Flash, PDAs Digital Still and Video Cameras APPLICATIONS ELECTRICAL SPECIFICATIONS Parameter Input Voltage LED Current (Torch) LED Current (Flash) (1) Symbol VIN IOUT1 IOUT2 Value 2.6 to 5.5 20 150 Units V mA mA “MPS” and “The Future of Analog IC Technology” are Registered Trademarks of Monolithic Power Systems, Inc. Note: 1) 5.5V input voltage limit is specific to the application circuit on this evaluation board. The input voltage limit of the MP1517 is 25V. EV0043 EVALUATION BOARD Waveform in Flash Mode VGATE 2V/div. VOUT 10V/div. 20ms/div. EV0043_TPC01 Dimensions (2.5”X x 2.0”Y x 0.4”Z) Board Number EV0043 EV0043 (MP1517) Rev. 1.1 2/17/2005 MPS IC Number MP1517DR www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 1 EV0043 (MP1517) – 3A, 25V, 1.1MHz STEP-UP CONVERTER FOR WLED APPLICATIONS EVALUATION BOARD EVALUATION BOARD SCHEMATIC SS Q1 NMOS ZXMN6A08E6TA C7 47nF SGND NC SS FB COMP NC IN C4 OPEN GND PGND PGND MP1517 SW SW IN BP EN OLS NC SGND GATE LED4 EN U1 LED3 OUT C2 OPEN D1 MBR0540 LED2 LED1 EV0043_S01 EV0043 BILL OF MATERIALS Qty 1 2 1 1 1 1 4 1 1 2 1 1 1 Ref C1 C2, C4 C3 C7 D1 L1 LED1, LED2, LED3, LED4 Q1 R1 R2, R3 R4 R5 U1 Value Description 4.7uF NS 10uF 47nF Capacitor, 25V, Ceramic X5R Do Not Stuff Capacitor, 6.3V Ceramic X5R Capacitor, 25V, Ceramic X7R Schottky Diode, 0.5A, 40V 4.7uH Inductor, 5.6A White LED, 40MCD N-Channel MOSFET 2.2kΩ Film Resistor, 5% 0 Film Resistor, 5% Package Manufacturer P/N 1210 Panasonic ECJ-4YB1E475K Taiyo-Yuden JMK325BJ106MF Panasonic ECJ-1VB1E473K Distributor P/N Digikey PCC2251CT-ND 1210 0603 SOD123 Digikey PCC1771CT-ND Digikey MBR0540T1OSCT-ND 34.8Ω Film Resistor, 1% 5.11Ω Film Resistor, 1% Step-Up Converter ON Semi MBR0540T1 Sumida CDRH8D43-4R7NC Lumex 1206 SML-LX23UWC-TR Zetex SOT23-6 ZXMN6A08E6TA Panasonic 0603 ERJ-3GEYJ222V Yageo 0603 9C06032A0R00JLHFT Panasonic 0805 ERJ-6ENF34R8V Yageo 0805 9C08052A5R11FGHFT MPS QFN16 MP1517DR Digikey 67-1607-1-ND Digikey ZXMN6A08E6CT-ND Digikey P2.2KGCT-ND Digikey 311-0.0GCT-ND Digikey P34.8CCT-ND Digikey 311-5.11CCT-ND EV0043 (MP1517) Rev. 1.1 2/17/2005 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 2 EV0043 (MP1517) – 3A, 25V, 1.1MHz STEP-UP CONVERTER FOR WLED APPLICATIONS EVALUATION BOARD PRINTED CIRCUIT BOARD LAYOUT Figure 1—Top Silk Layer Figure 2—Top Layer Figure 3—Bottom Layer QUICK START GUIDE 1. Connect LEDs to LED1 to LED4 terminals. 2. Connect positive and negative terminals of the 2.5V to 5.5V power supply to the IN and GND pins, respectively. 3. Drive GATE of Q1 with a pulsed signal to switch between two (2) LED currents. 4. The device is automatically enabled because EN is connected to IN through a 0Ω resistor (R2). It will be disabled only if VIN is removed. NOTICE: The information in this document is subject to change without notice. Please contact MPS for current specifications. 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. EV0043 (MP1517) Rev. 1.1 2/17/2005 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 3