1.25MHz, 600mA Synchronous Step-Down Regulator (Preliminary) Description SE3806 Features The SE3806 is a high efficiency monolithic ¾ High Efficiency: Up to 96% synchronous buck regulator using a constant ¾ Very Low Quiescent Current: Only 20μA frequency, voltage mode architecture. The device During Operation is available in fixed output voltage of 1.8V and 1.5V ¾ 600mA Output Current and adjustable output voltage. Supply current ¾ 2.5V to 5V Input Voltage Range during operation is only 20μA and drop to ≤1μA in ¾ 1.25MHz Constant Frequency Operation shutdown. The 2.5V to 5.5V input voltage range ¾ No Schottky Diode Required makes the SE3806 ideally suited for single Li-Ion ¾ Low Dropout Operation: 100% Duty Cycle battery-powered applications. 100% duty cycle ¾ Shutdown Mode draws ≤ 1μA Supply Current provides low dropout operation, extending battery ¾ Excellent Line and Load Transient Response life in portable systems. ¾ Overtemperature Protection ¾ Available in SOT Package Switching frequency is internally set at 1.25MHz, allowing the use of small surface mount inductors and capacitors. Application The internal synchronous switch increases ¾ Cellular Phone efficiency and eliminates the need for an external ¾ Personal Information Appliances Schottky diode. ¾ Wireless and DSL Modems profile SOT package. ¾ Digital Still Cameras Pin Configuration ¾ MP3 Players ¾ Portable Instruments The SE3806 is available in low 5 Lead SOT-23 Application Diagram Revision 12/4/2008 Preliminary and all contents are subject to change without prior notice © Seaward Electronics, Inc., 2004. • www.seawardinc.com.cn • Page 1 1.25MHz, 600mA Synchronous Step-Down Regulator (Preliminary) SE3806 OUTLINE DRAWING SOT-23-5L DIMENSIONS INCHES MM MIN MAX MIN MAX K B H D A F E C J DIMN A B C D E F H J K 0.110 0.059 0.036 0.014 0.0035 0.102 0.120 0.070 0.051 0.020 0.037 0.075 0.006 0.008 0.118 Customer Support Seaward Electronics Incorporated – China Section B, 2nd Floor, ShangDi Scientific Office Complex, #22 XinXi Road Haidian District, Beijing 100085, China Tel: 86-10-8289-5700/01/05 Fax: 86-10-8289-5706 Seaward Electronics Corporation – Taiwan 2F, #181, Sec. 3, Minquan East Rd, Taipei, Taiwan R.O.C Tel: 886-2-2712-0307 Fax: 886-2-2712-0191 Seaward Electronics Incorporated – North America 1512 Centre Pointe Dr. Milpitas, CA95035, USA Tel: 1-408-821-6600 Last Updated - 12/4/2008 Revision 12/4/2008 Preliminary and all contents are subject to change without prior notice © Seaward Electronics, Inc., 2004. • www.seawardinc.com.cn • Page 2 2.80 1.50 0.90 0.35 0.090 2.60 3.05 1.75 1.30 0.50 0.95 1.90 0.15 0.20 3.00