TM EV1542DK-SEPIC-00A 700KHz/1.3MHz Boost Converter with a 2A Switch The Future of Analog IC Technology TM EVALUATION BOARD GENERAL DESCRIPTION FEATURES The EV1542DK-SEPIC-00A is the demo board for sepic applications using the MP1542, a current mode step up converter with a 2A, 0.18Ω internal switch to provide a highly efficient regulator with fast response. The EV1542DK-SEPIC-00A 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. The soft-start results in small inrush current and can be programmed with an external capacitor. The EV1542DK-SEPIC-00A can operate from a single Li-Ion battery to generate 3.3V at up to 500mA. • • Other features include under voltage lockout, current limiting and thermal overload protection, all available in a low profile 8-pin MSOP package. “MPS” and “Monolithic Power Systems”, are Trademarks of Monolithic Power Systems, Inc. • • • • • Automatic Up-Down Conversion Operates from a Single Li-Ion Battery to Generate 3.3V at up to 500mA Uses Tiny Capacitors and Inductors Pin Selectable 700KHz or 1.3MHz Fixed Switching Frequency Programmable Soft-Start UVLO, 2A Switch, Thermal Shutdown Internal Current Limit APPLICATIONS • • • • LCD Displays Portable Applications Handheld Computers and PDAs Digital Still and Video Cameras ELECTRICAL SPECIFICATIONS Parameter Symbol Value Units VIN VOUT IOUT 3 – 4.2 3.3 500 V V mA Input Voltage Output Voltage Output Current EV1542DK-SEPIC-00A EVALUATION BOARD Efficiency vs Load Current 90 EFFICIENCY (%) 80 VIN=4.2V 70 VIN=3.6V 60 50 VIN=3V 40 30 20 Dimensions (2.0”X x 2.0”Y x 0.0”Z) Board Number MPS IC Number EV1542DK-SEPIC-00A MP1542DK 10 0 1 10 100 LOAD CURRENT (mA) 1000 EV1542_EC02 EV1542DK-SEPIC-00A Rev. 1.0 www.MonolithicPower.com 6/15/2005 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 1 TM EV1542DK-SEPIC-00A — 700KHz/1.3MHz SEPIC CONVERTER WITH A 2A SWITCH EVALUATION BOARD EVALUATION BOARD SCHEMATIC VIN 3V - 4.2V GND T1 COOPER DRQ73-3R3 D2 1N4148 D1 1N5819HW-7 6 3 EN IN EN SW 5 VOUT 3.3V 0.5A C2B NS JP1 FREQUENCY SELECTION 7 FSEL MP1542 FB 2 GND 8 SS C4 22nF GND U1 COMP 1 4 C6 NS C3 1nF EV1542-SEPIC_S01 EV1542DK-SEPIC-00A BILL OF MATERIALS Qty Ref Value Description 2 C1A, C1B 10µF Ceramic Cap, 6.3V, X5R 1210 TDK C3225X5R1A106K 1 C2A 22µF Ceramic Cap, 6.3V, X5R 1210 TDK C3225X5R0J226M 1 C3 1nF Ceramic Cap, 50V, X7R 0805 TDK C2012X7R1H102K 1 C4 22nF Ceramic Cap, 100V, X7R 0805 TDK C2012X7R2A223M 1 C5 4.7µF Ceramic Cap, 10V, Y5V 0805 TDK C2012Y5V1A475Z 2 C6, C2B NS Not Stuffed 1 C7 1µF Ceramic Cap, 10V, X5R 0805 TDK C2012X5R1A105K 1 D1 Schottky Diode, 40V, 1A SOD-123 Diodes Inc 1N5819HW-7 1 D2 Rectifier Diode, 75V, 200mW SOD-323 Diodes Inc 1N4148WS-7 1 JP1 3-Pin Connector Header, 0.100 Sullins PTC03SAAN 1 L1 3.3µH Transformer, 1.66A Cooper DRQ73-3R3 1 R1 16.4kΩ Metal Film Resistor, 1% 0805 Panasonic ERJ-6ENF1642V 1 R2 10kΩ Metal Film Resistor, 1% 0805 Panasonic ERJ-6ENF1002V 1 R3 20kΩ Metal Film Resistor, 5% 0805 Panasonic ERJ-6GEYJ203V 2 R4, R5 100kΩ Metal Film Resistor, 5% 0805 Panasonic ERJ-6GEYJ104V 1 U1 MSOP8 MPS MP1542DK DC-DC Converter Package Manufacturer EV1542DK-SEPIC-00A Rev. 1.0 www.MonolithicPower.com 6/15/2005 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. Manufacturer P/N 2 TM EV1542DK-SEPIC-00A — 700KHz/1.3MHz SEPIC 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-SEPIC-00A Rev. 1.0 www.MonolithicPower.com 6/15/2005 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 3 TM EV1542DK-SEPIC-00A — 700KHz/1.3MHz SEPIC CONVERTER WITH A 2A SWITCH EVALUATION BOARD QUICK START GUIDE The output voltage of this board is set to 3.3V. The board layout accommodates most commonly used inductors and output capacitors. 1. Preset the power supply to 3V ≤ VIN ≤ 6V. 2. Turn the power supply off. 3. Connect the power supply terminals to: a. Positive (+): VIN, EN b. Negative (–): GND 4. Connect the load to: a. Positive (+): VOUT b. Negative (–): GND 5. Turn on the power supply 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 formula: ⎛V ⎞ R1 = ⎜⎜ OUT − 1⎟⎟R2 ⎝ VFB ⎠ Where VFB = 1.25V and R2 = 10kΩ For example, for VOUT = 5V ⎛ 5V ⎞ − 1⎟ × 10kΩ = 30kΩ R1 = ⎜ ⎝ 1.25 V ⎠ Therefore use a 30.1kΩ standard 1% value. 8. The switching frequency is set to 1.3MHz if jumper JP1 is shunted at the H position. To get 700KHz operation, shunt JP1 at the L position. 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-SEPIC-00A Rev. 1.0 www.MonolithicPower.com 6/15/2005 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 4