EV2351DQ-00A 4.75V to 23V Input, 1.5A Output Step-Down DC/DC Converter The Future of Analog IC Technology EVALUATION BOARD - INITIAL RELEASE GENERAL DESCRIPTION FEATURES The EV2351DQ-00A is the Evaluation Board for MPS’ MP2351 Step-Down DC/DC Converter. It features a wide supply range of 4.75V to 23V and a continuous output current up to 1.5A. The output voltage is set to 3.3V, but can be easily adjusted to other levels from 1.22V. A 1.4MHz high switching frequency allows the use of small, low cost capacitors and inductors. Current mode control and an integrated power MOSFET minimize component count, board area, and solution cost. Fault condition protection includes cycle-by-cycle current limiting, thermal shutdown, and under-voltage lockout. Internal soft-start reduces the turn-on stress. The small 10-pin QFN package minimizes board area. • • • • • • Up to 1.5A Output Current Wide 4.75 to 23V Operating Input Range Monolithic Buck with 180mΩ Internal FET Fixed 1.4MHz Frequency All Ceramic Input and Output Capacitors Programmable Input Under-Voltage Lockout APPLICATIONS • • • • Distributed Power Systems Battery Chargers DSL Modems Pre-Regulators for Linear Regulators “MPS” and “The Future of Analog IC Technology”, are Registered Trademarks of Monolithic Power Systems, Inc. ELECTRICAL SPECIFICATIONS Parameter Supply Voltage Output Voltage Output Current Symbol Value Units VIN VOUT IOUT 4.75 – 23 5 0 – 1.5 V V A EV2351DQ-00A EVALUATION BOARD Efficiency vs Load Current 100 VOUT=5V EFFICIENCY (%) 90 VOUT=2.5V 80 70 VOUT=3.3V 60 50 Dimensions (2.1”X x 1.3”Y x 0.4”Z) Board Number MPS IC Number EV2351DQ-00A MP2351 EV2351DQ-00A Rev. 1.1 3/29/2005 40 0 300 600 900 1200 1500 LOAD CURRENT (mA) www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. MP2351-EC01 1 EV2351DQ-00A – 4.75V TO 23V INPUT, 1.5A OUTPUT STEP-DOWN CONVERTER EVALUATION BOARD - INITIAL RELEASE EVALUATION BOARD SCHEMATIC C6 OPEN R4 OPEN SYNC EN R5 OPEN C7 OPEN SYNC NC EN BS C1 10nF C3 1nF MP2351 COMP NC C8 OPEN VIN VOUT FB IN SW GND C8 OPEN D1 B340A-13 EV2351_S01 EV2351DQ-00A BILL OF MATERIALS Qty 1 1 1 1 4 1 1 1 1 1 2 1 Ref C1 C2 C3 C5 C4, C7, C6, C8 D1 L1 R1 R2 R3 R4, R5 U1 EV2351DQ-00A Rev. 1.1 3/29/2005 Value 10nF 10µF 1nF 22µF Description Ceramic Capacitor, 50V, X7R Ceramic Capacitor, 25V, X5R Ceramic Capacitor, 50V, X7R Ceramic Capacitor, 16V, X5R Package SM0805 SM1210 SM0805 SM1210 Manufacturer AVX AVX AVX AVX Manufacturer P/N 08055C103KAT2A 12103D106KAT2A 08055C102KAT2A 1210YD226KAT2A SMA SMD SM0805 SM0805 SM0805 Diodes Inc Sumida Panasonic Panasonic Panasonic B340A-13 CDRH6D28-5R0NC ERJ-6ENF1692V ERJ-6GEYJ562V ERJ-6ENF1002V QFN10 MPS Do Not Stuff 5µH 16.9kΩ 15kΩ 10kΩ Diode Schottky, 40V, 3A Inductor, 2.4A Film Resistor, 1% Film Resistor, 5% Film Resistor, 1% Do Not Stuff Step-Down Converter www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. MP2351DQ 2 EV2351DQ-00A – 4.75V TO 23V INPUT, 1.5A OUTPUT STEP-DOWN CONVERTER EVALUATION BOARD - INITIAL RELEASE PRINTED CIRCUIT BOARD LAYOUT Figure 1—Top Silk Layer Figure 2—Top Layer Figure 3—Bottom Layer QUICK START GUIDE 1. Connect the positive terminal of the load to VOUT pins, and the negative terminal of the load to GND pins 2. Preset the power supply output to 4.75V – 23V and turn off the power supply. 3. Connect the positive terminal of the power supply output to the VIN pin and the negative terminal of the power supply output to the GND pin 4. Turn the power supply on. The MP2351 will automatically startup. 5. To use the Enable function, apply a digital input to EN pin. Drive EN higher than 2.5V to turn on the regulator, drive EN less than 0.7V to turn it off. 6. An input under voltage lockout (UVLO) function can be implemented by the addition of a resistor divider R4 and R5. ⎛ R4 ⎞ The EN threshold is 2.5V, so VIN UVLO threshold is: ⎜1 + ⎟ × 2 .5 V . ⎝ R5 ⎠ 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. EV2351DQ-00A Rev. 1.1 3/29/2005 www.MonolithicPower.com MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited. © 2005 MPS. All Rights Reserved. 3