MP1542DK

TM EV1542DK-00A 700KHz/1.3MHz Boost Converter with a 2A Switch EVALUATION BOARD The Future of Analog IC Technology TM GENERAL DESCRIPTION The EV1542DK-00A is the evaluation board for the MP1542, a current mode step-up converter with a 2A, 0.18Ω internal switch to provide a highly efficient regulator with quick response. The MP1542 can be operated at 700KHz or 1.3MHz allowing for easy filtering and low noise. An external compensation pin gives the user flexibility in setting loop dynamics, which allows the use of small, low-ESR ceramic output capacitors. Soft-start results in small inrush current and can be programmed with an external capacitor. The MP1542 operates from an input voltage as low as 2.5V and can generate 12V at up to 500mA from a 5V supply. The MP1542 includes under-voltage lockout, current limiting and thermal overload protection preventing damage in the event of an output overload. The MP1542 is available in a low profile 8-pin MSOP package. FEATURES • • • • • • • • • • • • • 2A, 0.18Ω, 25V Power MOSFET Uses Tiny Capacitors and Inductors Pin Selectable 700KHz or 1.3MHz Fixed Switching Frequency Programmable Soft-Start Operates with Input Voltage as Low as 2.5V and Output Voltage as High as 22V 12V at 500mA from 5V Input UVLO, Thermal Shutdown Internal Current Limit Available in an 8-Pin MSOP Package LCD Displays Portable Applications Handheld Computers and PDAs Digital Still and Video Cameras APPLICATIONS “MPS” and “Monolithic Power Systems”, are Trademarks of Monolithic Power Systems, Inc. ELECTRICAL SPECIFICATIONS Parameter Input Voltage Output Voltage Output Current Symbol VIN VOUT IOUT Value 2.5 – 6 8 400 Units V V mA EV1542DK-00A EVALUATION BOARD Efficiency vs Load Current 95 90 EFFICIENCY (%) 85 80 75 70 65 60 55 VIN = 3.3V VOUT = 8V 1 10 100 LOAD CURRENT (mA) 1000 Dimensions (2.0”X x 2.0”Y x 0.4”Z) Board Number EV1542DK-00A EV1542DK-00A Rev. 1.2 6/8/2005 50 MPS IC Number MP1542DK MP1542-EC02 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 1 TM EV1542DK-00A — 700KHz/1.3MHz BOOST CONVERTER WITH A 2A SWITCH EVALUATION BOARD EVALUATION BOARD SCHEMATIC VIN 5V JP1 1 3 2 7 3 8 D1 1N5819HW-7 VOUT 8V 6 IN FSEL EN SS 5 SW FB 2 OFF ON MP1542 GND 4 COMP 1 C4 10nF C3 2.2nF C5 NS EV1542_S01 EV1542DK-00A BILL OF MATERIALS Qty 2 1 1 1 1 1 1 1 2 2 1 Ref C1, C2 C3 C4 C5 D1 JP1 L1 R1 R2, R3 R4, R5 U1 4.7µH 10kΩ Value 10µF 2.2nF 10nF Description Ceramic Capacitor, 10V, X7R Ceramic Capacitor, 50V, X7R Ceramic Capacitor, 50V, X7R Not Stuffed Schottky Diodes, 40V, 1A 3-Pin Connector Header, 0.100 2.01A, D53LC Film Resistor, 1% DC-DC Converter SMD 0805 0805 0805 MSOP-8 53.6kΩ Film Resistor, 1% 100kΩ Film Resistor, 5% SOD123 Diodes Inc Sullins Toko Panasonic Panasonic Panasonic MPS 1N5819HW-7 PTC03SAAN A915AY-4R7M ERJ-6ENF5362V ERJ-6ENF1002V ERJ-6GEYJ104V MP1542 Package 1210 0805 0805 Manufacturer Manufacturer P/N AVX AVX AVX 1210ZC106KAT2A 08055C222KAT2A 08055C103KAT2A EV1542DK-00A Rev. 1.2 6/8/2005 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 2 TM EV1542DK-00A — 700KHz/1.3MHz BOOST CONVERTER WITH A 2A SWITCH EVALUATION BOARD PRINTED CIRCUIT BOARD LAYOUT Figure 1—Top Silk Layer Figure 2—Top Layer Figure 3—Bottom Layer EV1542DK-00A Rev. 1.2 6/8/2005 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 3 TM EV1542DK-00A — 700KHz/1.3MHz BOOST CONVERTER WITH A 2A SWITCH EVALUATION BOARD QUICK START GUIDE The output voltage of this board is set to 8V. The board layout accommodates most commonly used inductors and output capacitors. 1. Preset Power Supply to 2.5V ≤ VIN ≤ 6V. 2. Turn Power Supply off. 3. Connect Power Supply terminals to: a. Positive (+): IN, EN b. Negative (–): GND 4. Connect Load to: a. Positive (+): OUT b. Negative (–): GND 5. Turn Power Supply on after making connections. 6. The MP1542 is enabled on the evaluation board once VIN is applied. To disable the MP1542, disconnect EN from IN. 7. The output voltage VOUT can be changed by varying R1. Calculate the new value using the fomula: ⎛V ⎞ R1 = ⎜ OUT − 1⎟R2 ⎜V ⎟ ⎝ FB ⎠ Where VFB = 1.25V and R2 = 10kΩ For example, for VOUT = 12V ⎛ 12V ⎞ − 1⎟ × 10kΩ = 86kΩ R1 = ⎜ ⎝ 1.25 V ⎠ Therefore use an 86.6kΩ standard 1% value. For output voltages greater than 10V, the output capacitor C2 needs to be replaced with a capacitor with a higher voltage rating suitable for the new output voltage. 8. The switching frequency is set to 1.3MHz if jumper JP1 is shunted between 1 and 2. To get 700KHz operation, shunt JP1 between 2 and 3. 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. EV1542DK-00A Rev. 1.2 6/8/2005 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 4